Professional Paper No. 24 Se . f A, Economic Geology, 31 nes (. C, Systematic Geology and Paleontology, 66 

DEPARTMENT OF THE INTERIOR 

UNITED STATES GEOLOGICAL SURVEY 

CHARLES D. WALCOTT, DIRECTOR 

ZINC AND LEAD DEPO~TS OF NORTHERN ARKANSAS BY 

GEOR.GE I. ADAlVIS 

SS TED BY 

A. II. P1J R .DUE A_NJ) E. ~~- BTTROI-IARD 

WITH A SECTIOK OK THE 

DETERlVIINATION AND CORRELATION OF FORlVIATIONS 

BY 

:F_:. C). 1J T .. RICJH 

1V ASHINGTON 

GOVERNMENT PRINTING OFFICE 

1904 
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CONTENTS. 

Page. 

:Letter of transmittal ............................... __ ..................................... . 11 

Introduction ................................ _ ......... _ .. _ ........ : ....... . ............. _·_. 13 

Scope of this report. ........................................................ . 13 

Historical sketch ......... _ .................................................. . 13 • 

Limits of the northern Arkansas district ....... : ........................ _·_ .. . 14 

Transportation facilities ............. _. __ .. _-_ .......... ~ ...... : .. _ ............. . 14 

Production of the district. ..... _ ..... __ ........ ~ .............. _ ..... . ........ . 15 

Pro.spective development. ................ _ .... _'. ; ............................ . 15 

8•1rface features ................. _ ..... _ ..... _ ...................................... __ ... . 16 

. General character of the country ............... _ . _ ........................... . 16 

Physiographic relations of the Ozark Plateau and Boston Mountains .......... . 16 

Divisions of the Ozark Plateau .................................•..•..•....... 17 

Low lands ................................ .- ........ _ .. _ ....... _ .............. . 17 

Pr~vious surface features ................. _ ................................... .' 17 

Description of geologic formations ....... _ .. __ ............ _. ____ .... _ .. . · .......... : ...... . 18 

Ordovician system .... __ ............ _ ................... _ ....... _ . _ ................... . 18 

Yellville formation _ ... ___ .. ____ .. ___ r ________________ • _______________________ _ 18 

Key sandstone ...................... _ ............ _ ...................... _ ... -. 20 

Izard limestone ............. __ ......... _ ..... : . ................... _-....... -.. . 21 

Polk Bayou limestone __ ... __ ... _ ... _ .... __ .. _ ... ___ . ~. __ ........... _ .. __ ... _. 22 

Devonian system ............ _ ... __ . _ ... _________ ... ____ ........ __ .. _______ . _ .. _ ..... . 22 

Sylamore formation .... __ . __ ....... _._ .... _ ... __ .... _._ ... __ ... _ .............. . 22 

Carboniferous system ...... , .. __ . ________ .. _._. _. _ ... · .. ___ .. __ .. _. _ .. _ ... _ .. _. ____ ..... . 24 

Mississippian series _ . 7 ••••••••• - •••• - • - - - • - ••• - - - - • - - - • - - - - - - - - • • - - - • • - - - - - - - - • • • - 24 

N oe] shale ............ _ ............ _ .. _ ..... __ .......... _ ...... . .... _ ....... . . 24 

Boone limestone and chert _ ........... _ ........ _ ..... _ ...................... . 25 

I Moorefield shale._ .. _ ...... _._. __ ..... _._ ... __ . _____ ... __ ........... .......... . 26 

Batesville sandstone .. _ ... _ .......... __ .. _ .. _ .. __ ........ ----..... -... --. -... . 26 

Fayetteville shale ..... _ ..................... _ .................. __ . _ .. _ ...... . 27 

Pitkin limestone ......... _ .. _ ............................ : ............... -'-.. . 27 

Pennsy 1 vanian series ........... _ .............. __ ............ _ . _ ........ ~ . _ ....... . I 28 

Morrow formation __ . _ ........................ _ .... ____ .. _ ........ ___ . _ ..... _ . 28 

Winslo\'\' formation _ ..... _ ........ __ ........... _ ........ _. _ .... _. _ .. _ ....... _ ~ 29 

Grouping of the rocks with respect to ore deposits_ ... _ ... _ .. _ ........ ~ ......... . 29 

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4 CON'l'ENTS. 

Page. 

History of physical changes ______ •...•• _ •..•••.•. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 29 

Sedimentation _________________________________ • __________ • _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 29 

Erosion-----------·---·-·-·-------------------------------------------------- 31 

I>eformation ________________________________ ~----------------------····---·--- 32 

Origin of structure·---------------------------------------------------~------· 33 

Geologic conditions influencing circulation of ground water _ .... _. _ . _. _ . __ .• _.. 34 

Synclines_ .••.•.. _ ••. _____ . __ . ___ ..•.•..• __ ••••• ___ •. _ .. _ .. ___ • ___________ • __ • 35 

Relations of belt of weathering and belt of cementation_ ....•.... ___ •........• 35 

Principal faults ___ ••.• __ . ______ . _ ~ . _. _ ..•.. _ •. ____ . _. _______ . _____ ••. _ . ___________ . ___ •. _. 36 

Rush Creek fault . _ . _ . ________ • _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 37 

Tomahawk fault._____________________________________________________________ 37 

Pilot Mountain fault. _________________________________________________ ~_______ 37 

St. Joe fault._________________________________________________________________ 38 

Mill Creek .fault __________________________________ ... _ .. _ ....... ____ .. _ ..... _ _ 38 

• St. Joe monocline ...... _ ..... _ .. : . . __ •.... ___ . __ ... _ . ___ .. _ ................. . 38 

Hurricane fault ......... __ .. _ .. ____________ ._ ..... _. ______ .................... 39 

Ores and minerals .. __ . _ .... _ . _ . ___________________________ ............. ______ .. ___ .. ____ . 39 

Sulphide ores._. ___ .. _. __ .. _. __ ._· ________ . _______________ . __ ..... __ . _____________ . _____ . 39 

I Zinc sulphide, or sphalerite .•... ___ .. _ .. __ . _______ .............••.•.... _ _ _ _ _ _ _ 39 

Lead sulphide, or galena ___________ . __ .... _. _ ... ___ . _ .. _ ...... _. __ .. _ .. _ ... __ ~ 39 

Oxidized ores. ___ ~ ___ • __ ._~_ ..• _ ..... _ .. _. _________ . __ ..... _ .......... __ .... _. ___ ._... 39 

Zinc silicate, or calamine _____ . ______ .... __ .. __ . _ . __ . __ ................ - - - -. --. 39 

Zinc carbonate, or smithsonite ___ . _ .. _____ . _ ............ _____ .. _ ........ ---- __ - 40 

Hydrozincite ____________ . ___ -·- __ .. _____ . ____ .. ______ .. _. _ ... _ .... -.. ----- _--- 40 

Lead carbonate, or cerussite ____________ . _ .. _ .. ____ .. __ -- - . - - - -. - ---- . - - -. --... 40 

Hydrocerussite ... ___ . ____ . __ . __________ ... _. __ . ___ . _ ... _. _______ .. __ . _ .. __ .. _ 40 

Tallow clay ______ . ________________ . ____ ... _ .. _ .... _ . ___ -_ .... __ . _ .. ____ . _ _ _ _ _ _ 40 

Associated minerals __ • ______________ . ___________ .... __ ..... _ ... _________ .. _ _ _ _ _ _ _ _ _ _ _ _ 41 

I>olo~ite spar, or pink spar_ .. _ ..... ______ ........ _ ..... _ ... _______ - ___ .. - _---- 41 

Calcite, or tiff. ____________ . ___ . _____ ._ .. ___ .. __ .. ____ . ____ . __ .. ______ ... ___ --_ 41 

Secondary chert . _ •. _ ..•. . . _ . __ .. ________________ - - - - - - - __ . _ .. _ ---- -- - - - - - - - - - 41 

Quartz ___________ :;.- ______ . _____________________ .. ______ . __ ... __ .. ___ . ___ . _ . _. 41 

Iron sulphide, or'pyrite. ____ . __ .. ___ . __ .. _ .. ____ ~.- .. ---. _ .. -----.-.----------- 41 

Chalcopyrite. _______ - ___ . _____ --.----- ... ---------- 7 -- -.-·---------------------- 42 

Gypsum ____________ . _ . ___ .- ____ . _______ . _ . ___ .. _ ... ______ . _____ : __ ~ ... - - -... -- 42 

Epsomite __ .. ________ ·- _________________ . ___ . ______ - - - --- ____ . - - --- -- . - - -. -. - - - 42 

Goslarite ________ • ________ - _____ .. __________ . .. . - - - -. -. -. -- - - - - -. - - - - - - --- - --- - 42 

Country rock._. __________ . ___ .---_------ __ -----.------------------------------------- 42 

Prevailing gangue minerals _____________ .. _ . _ .. _____ . -- - - - - -. - - - --. - - - --- . - - - ------- - - - 43 

Genesis and classification of ore deposits .. _. __ ... -....•. - - - - . ----- -- -- - - ----. -- - --- --- 43 

Source of ores __ •.•.•• __ . ___ .. _______ . ___ •... - - -.. - - - - -.. -- - -·-.. - -• - --- ---- --- 43 

Classification of the ore deposits __ ... __ ... - -• -•• -.-•... -....•.•.. ----- - - - ----- 44 

Processes of primary deposition of the sulphide ore~ •.•.. ___ ... - - - - -- - - - - - -. - - 44 

Processes . of deposition of the oxidized ores ______ . _-------.----.- ... ---------- 44 

Secondary deposition of the sulphides. _____ ._ .. _ .... -..... -- .••........ ~ .. -... 45 
CONTENTS. 5 

Ores and minerals-Continued. 

Genesis and classification of ore deposits-Continu~d. Page. 

Sulphide deposits associated with secondary chert •......••...•••............. 45 

'Sulphide deposits in bedded breccias .............................. ~.- ~ ....... . 46 

Sulphide deposits in fissures ......•••••••....•.....•.......................... 46 

Sulphide deposits in fault breccias ..•.•.••...... : ............................ . 46 

Sulphide ore in the country rock ..•....•..................................... 46 

Ore associated with qua.:rtz druses .. _·_ ..................... _ .......... _ ....... . 46 

,Descriptions of mines and prospects .......................................... ~ .....•..... 63 

Boone County .....•........... _ ....... _ ... _ .................. _ ..... _ ................ . 63 

Northern Star. .. . . . ................................... _ ...................... . 63 

Willis .... , .................... __ .. __ . _ ........ _ .. _ .. __ ...... _. ____ ........... . 64 

Elixir ......................... _ .. ___ ..•................... _ ... _ ............. . 64 

Almy .......... ." .............. _____ .. ___ . ___ ...................... _ .......... . 65 

Jackpot ....... ' .......... _ ....... _ .... ........ ____ . _ . _ ......... ; .-............ ~ 65 

Frisco ......•.............................................. : ................. . 66 

Virginia J ... -....... ~ ... _ ......... ___ ... ___ · '7. •••••••••• _ ••••• _ ••••••••••••••••• 66 

Marion County ..................... __ . _ ... _ .. _ .. --..... _ .... __ ....................... . 66 

. lola ............................................... --.. -... ~ -... -- ------ ------ 66 

Tallow Clay ....................... . .... _ .... _ .. _ ............................ . 67 

Colorado ............................................. _ ................. _ ..... . 67 

Ben Harrison ............. _ ... _ .................. ______ . ___ .... __ ........... : 67 

~arkle ...••.. ------------- ---------------------------------------------······ 67 

Pilot Rock .. _ .... _ .......... ___ .. __ . __ ... __ ... ___ ..... _ ... ___ .... __ . _ ....... . 68 

N akomis ................. _ .... __ .............. _ . _ . ____ . _____ . _ .. __ .. ___ ..... . 68 

Governor Eagle .............. __ ...... ~ .. _ . __ .. _ ....... _ .............. _ ........ _ 68 ~ 

Susquehanna __ ... ___ .. __ ...... _ .. ___ .. _. _. _ ... _____ . _ ......... ·-. _ . . . _. _ ..... . 69 " 

Tar kiln . _ ................ __ . _____ _ - ______ . _________________________________ . __ 69 

Bear Hill _ ............. __ ..... __ . _. ___ ... __ . _ .. _______________ .. __ . __ .. _. _ .. . 69 

Batie ... _ .......... _ ......... _ ... __ .......................................... . 69 

Big Elephant ....... __ . ___ . _____ ... __ . _______ .. __ . _. __ . _ .. ·. _ .... ____ .. ___ . __ _ 7(} 

Big Buffalo .. ___ ... _. _ .. ___ .... _. _. __ .. _____ .. __ ....... _ . ___ ... -- ___ . _. _______ . _ 70· 

Olympia . __ ... _. _. _. __ .. ___________________________ .. _____________________ .... . 7(} 

North Star ....... ___ . __ . _ . _ ......... _ ... ___ ... _ ...... __ ... __ .... _ ... _____ .... . 71 

Sumn1it Home .. ___ .... ____ . _. _ ... _. ___ . __ . _. ___ . ____ ... _____ .. _. __ ........ __ _ 71 

Dyson. ___ .. _ .•..... _. __ . ___ .... __ . ______ .. _________ ~ ___________ .. ____ . __ . __ . _ 71 

Bald Jesse .. ............. _ ..... _ ............................................ . . . 72' 

Ha ,.., keye. _ .................................. _ .. __ . _ .... _ .. _. _ ... __ ... _ ... ___ _ 72 

Starlight ~ ................ ____ .. _ ... _ .......... _ .... _ ...... _-... ___ . _. ~ _. ____ .. 72' 

Eldorado ................................................ _ ... __ ........ _ ..... . 72 

Beulah .................. _ .... _ . _ ... _ ..• ___ ..... _ .... __ . ______ . ______ . __ . _____ _ 72 

Zinc Basin . _ .. ___ .. ______ . _ . _ . ____ •.•..•••......•.•....... __ .. __ ... ·. ________ _ 73 

Climax : . . _ .. __ . _ . _ . . _ ....•. _ ... _ ~ ___ •••..•• _ •.• __ ••• ____ •• _____ .. ___ . ___ . ___ . 73 

~orning Star_._. . . . . . . . __ .... ___ . _. __ .. ____ . _ ..•....•. _ ..•• _ . . _. __ . _. _ . _ ... _ 73 

Mcintosh ...... ___ . _ , ·- . ____ ·- ____ . ________ .. __ ••••.•••.•.••.. _ ... __ . _. _ ..•••... 74 
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6 CONTENTS. 

Description of mines and prospects-Continued. 

Marion County-Continued. 

White Eagle _. _ .............. _. ___ ............. ______ . _· _____ ... __ .... __ ..... . 

Maryhattiana-.................... _ ... ____ .. _ .............. _ ... _. ___ .. ___ .. __ .. 

Red Cloud .. _ .... _ .... _ . _ .. _ ...... _ ... __ . ____ ..... __ .. __ ... ___ --.. __ . ___ . ____ _ 

Silver Hollo"' _. _ ............. __ .......... ____ . ______ . ____________ . __________ _ 

Boat Creek_ . __ ..... _ ......... _ . ____ ... _ .... __ .. __________ . ____ . ________ . ____ _ 

, San1 HilL_ ............... ______ ... _. __ ... __ . ____ . __ . ___ ... _ ... _. ____ . __ .. _. _. 

Bonanza ....... ___ . ~ _____________ . ____ ...... _ .. _____ ...... __ . _ . __ . _ . _ •.. ___ . _ 

Christie _ . _ .. __ ... __ . ____ . _ . _____ .. _ ..... _ ~ __ .. __ . __ ~ ....... ________ ...... ___ _ 

Baxter County ___________________ . ___ . _ . __ . __ . _ ...... _ . ___ . __ ....... _ ...... _ .. __ .. _ .. _ 

Hawkeye No. 1 ____ . ___ · ___________ . _ ... ______ .. ___ .. _ .. __ . _ ....... __ . _ .... __ _ 

H ulsen beck _____ . ____________________ ..... _ . __ . _ . _ . _ . _ . _ ...... _ .......... __ .. 

Gambetta _______________ . ____ . _. ________ . ________ .. _. _ _. _ ..... ___ . _. _ ..... _. __ 

Lost 1\1ine . _ . _________ .. __ . _ . ____ . _____ .. __________ . ______ . ____ ........ ____ . __ 

Hopeful ... ______ . _______ ~ __________ .. _______ ._. ____ ..... __ ..... _. _ .. _. _ .. ___ _ 

Bald Dave . _ ... _ . _____ ...... ; ..... -- -. -. -. - -. - . - - --. -. - - - - - - ~ ~ -... - . - . - . - - - - . 

Gold Standard and Mark Hanna _______ . ___ .. 1• __________ • ____ ~ ______ ••••• _. _. 

Cedar Gap ________ . ______ .. __ ... ___ .. _. __ . ____ . __ . _. __ . __ ..... ___ ·- _. _ .. ______ _ 

Hawkeye No. 2 _______________________________________________ . _____________ . 

Big John _____________________________ . _ . _______ . _____________________ . _ . ____ _ 

'lvV allace Knob ______ . __ . ________________________ ~ -. _ . ________ . ___ • __ . _ . _ ... ___ _ 

Searcy County _________ ~ __ . ________ . ____________ -_________ . _______ ~ ___________________ _ 

Winchester_. ___ . __ . __________ . _____ . _____________ . ___ .. __ ................ ---. 

Jackpot (on Buffalo Fork) .. _____________________________ . __________________ _ 

Maumee ___ .. __ . _______ ............ ---- -. - . -. --- - -.. - - - - - - - - - - - . ---- -- . - - -.. -. 

Mud Hollo'v _ .. _ ..... ___ . _ ... _ ... __ ... ___ .... ____ .... __ .. _ .... ___ . c •• ______ • _ 

Excelsior (formerly St. Joe) _ .. ________ ... __ ......... __ ... _ ... __ .. _____ .. ___ : _ 

Davy Crockett. __________ ._. ____ .... _ ........ _. ____ . ___ . _____ . _. ____ . _. ______ . 

Big Hurricane. __ _. __ .. _ .. ___ . ____ ._. ___ ...... __ .... _ .... ___ ._ ... _ .. _. ______ _ 

Newton County __ . __ . ____ __ . _. ___ . ______ .... ___ .. __ .... __ ............... __ .... '....... . 

Spier ___ . __ . _ . ___ . _ . _ .. _ ... _ .. __ .... _ ......... ~ ...... _ ... _ .... _ . __ ......... __ . 

Marble City __________ ... _____ .. ___ ..................... ~ .................... . 

Canton .... _ ....... -.. -.----.--.--- .. -...... -- ... -... -.... -... - 7 •••• - ••• -.----

Wichita Belle _ ....... __ ... _ .. _. _. __ .... __ ... _ .. __ . _ .... _____ . ___ . _ ..... _____ _ 

Old Granby _____ ..... _______ . ___ ... _ ... _ ... ___ . _. ________ ........ _ ... __ . ____ _ 

Carbonate i\oEe.· __ .. _ ....... ______ . ___ ... __ ......... -....................... _ .. 

Goswick . _______ ... _ .. _ . _ .. ____ . ___ . ___ . _ ..... _ ..•. _ .... ___ .. ___ .. __ ·_ ... _ . _ ... 

Panther Creek ____ . __ . ___________ . ____ .. __ ... ___ -. __ ....... _ ... ____ ........ __ . 

Chimney Rock .. _ .. ______ ... ____ .. _ . _ . _ . ___ . _____ ... _ .. __ . _____ . _ . _ .. ____ . __ _ 

Baker & McGrath _____ .... _ .... _ . _ .... __ . _ . _ ... __ .. __ .... __ ... ___ . __ . _____ . _ . 

Bonanza ... _______________ . ________ .. ___ . ___ . ___ .. _____ ..... ____ . ____ ._ ... ___ . 

Ponca City . _________ ........ _ .......... _ ....... ~ ............................ . 

Bennett ____ ..................................... - -..... - -.... -.. - - - - - - - - - . - . -

Suggestions for prospecting and mining ........ ___ ..... __ ............. _ ..... _. __ . _._ ...... . 

Opinions of previous writers ............................ ___ . __ ......... _ ... _ .... _ ........ . 

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CONTENTS. 7 

Page. 

Determination and Correlation of Formations, by E. 0. Ulrich. .. ........................... 9q 

Description of correlation table .... ~ ........................•........................ _ 91 

Evidence upon which the cor:~·elations are based ........ ______ .. _. ___ . _ ... ____ . _____ . _ 93 

Ordovician formations _ ........... __ ................. _· ... _ .. · ............... _ ..... _ .. _ _ 93 

Yell ville limestone ....... _ .. _ .... _ ......... _ ... __ ..... _ . _ . _ .. __ J • •••• _ • __ • • • • 93 

Key sandstone ...... __ ... _ ........ _ .- ....... ___ . __ ..... _ ..... __ .. _______ ___ .. _:_ 95 

Izard li1nestone ................. ____ ....... __ .... _ " ___ . __ . ·- _ ....... _. ____ ..... 97 

Polk Bayou limestone . _ ... _ ........ _ ...... ___ ~ _. _ .. _ ·_ ... ___ · _______ .... ___ ·,-.. 98 

Silurian formations _ . _. _ .. ~ ...... _ .... _ . __ ............ _ ........... ______ . ________ . . . . . 98 

St. Clair limestone ....... _._ ... ____ .. __ . ___ ..... __ ._. ____ . ____ : .. ___ ..... ___ ... 98 

Devonian rocks ...... _ ................................. _ ..... _. __ ... _ .. ____ . _. _. _ .... _ 100 

Sylamore formation ......... _ .. _. ______ ._ .. ____ ' _____ .. _. __ .... _ ....... _ .. _ ... _. 100 

Carboniferous formations ....... _ ........................... _ . _ ... __ ........ _ .... _ . . . . . 101 

Lower Mississippian formations _ ... ___ ..... _______ .. -......................... _.... 101 

Noel shale and B'oone limestone ..... _ .................. _ . _ ........ _. . . . . . . . . . . 101 

Upper Mississippian formations ........ _ .. __ . ______ . _. __ ... __ ..... _ .. _............ 102 

Moorefield shale (Fayetteville shale in part of Branner) ....... _ ........ __ .... 102 

Batesville sandstone (Batesville sandstone of Branner, not Simonds;' Wyman 

sandstone of Simonds) ......... _ ... _ .. _ . __ . _ ................... _ .......... ~. 104 

Fayetteville shale (Fayetteville shale of Simonds and Branner and Marshall 

shale of Branner) .•.................... __ ... _ .............. ___ . __ ... _ . __ . . _ 106 

W edington sandstone (Batesville sandstone of Simonds) . __ ...... ____ . ___ .. _ _ _ _ 1 08 . 

Pitkin limestone ................... _ . _________________ ..... _ .... __ ........... _ 109 

Early Pennsylvanian formations ..... _. ___ .... _ ... _ .. _. _______ .. _ ...... _ .. _._. ___ ._ 109 

Morrow formation ..... . ___ . ____ . _ . _ . _ . _ ... __ ....... _ .... ___ ... _, ... ___ ..... _.. 109 

Index ..•................ ____ ................ _ .............•..... _ _ _ _ .......... __ . . . . . . . . . 115 
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ILLUSTRATIONS. ' 

Page. 

PLATE I. Map of north Arkansas zinc and lead district, showing general geology and principal 

mines' and prospects ............. _ ............ ------ ...... ------_. _______ .______ 14 

II. A, Sketch map of the Ozark region, showing the drainage and topography; B, 

Sketch map of the Ozark region, showing physiographic features .. _ .. -... -- _.--. 16 

III. A, Escarpment of Halls Mountain, 5 miles distant, seen from the north looking 

across Crooked Creek Valley; B, Bottom land along White River, near Gasville, 

loo)dng northwest from mountain east of Dentons Ferry ___________ ... _____ ----- 16 

IV. Geologic map of the northern part of the Yellville quadrangle, Arkansas._._______ 18 

V. Geologic map ?f the southern part of the Yellville quadrangle, Arkansas. __ ..... __ . 20 

VI. A, Richmond Bluff, near Amos post-office, in Baxter County; B, Engles Bluff, 

near Sylamore, in Izard County _. __ ... __ . _. ___ . ___ . _ .. _ ....... ____ . ___ ... _. _ _ _ 22 

VII. A, Ledge of St. Joe limestone member; B, Ledge of Key sandstone ..... ___ .. ___ . 24 

VIII. A, Mass of silicified breccia marking the St. Joe fault, near the Excelsior mine; 

B, Near view of dolomite breccia, cemented with pink spar_ .... -_ .. _ ... ---.--.. 34 

IX. Hand specimens illustrating genesis of ores. ____ .. __ . __ . __ .... _ ....... _--._.--- .. - 48 

X. Hand specimens illustrating genesis of ores. ____ . __ . __ .. __ .. __ ... _ .. __ .. ____ ._.___ 50 

XL Hand specimens illus~rating genesis of ores._ .... _. _______ ... _ ... ____ ._. __ .. ______ 52 

XII. Hand specimens illustrating genesis of ores. ____ .. __ ...... __________ . ____ .. _______ 54 

XIII. Hand specimens illustrating genesis of ores ...... _ .... ___ ._ ... __ .. __ . __ ... ____ .. __ 56 

XIV. Hand specimens illustrating genesis of ores .. ___ .. __ .... ______ . __ ...... _ .... ___ . _. 58 

XV. Hand specimens illustrating genesis of ores .. _. __ ._ .. __ . ___ . _____ ..... __ . _. ___ . __ . 60 

XVI. Hand specimens illustrating genesis of ores. ____ . ___ .. ____ .... ___ ....... -- .. ------ (}2 

XVII. A, Open cut in barren ground near lola mine, showin15 jointed dolomite; B, 

Almy mine ____ ... __________ .. _____ . _ .. ____ ... _. _. ________ . ______ . ________ .. _ _ _ 66 

XVIII. A, Open cut Big Elephant mine, Key sandstone in upper part of exposure; B, 

Markle mine hand jigs _______ ... ___ . __ . _ . _________ .. __ . ____ . _ . ___ .. _ . ______ . _ . 68 

XIX. A, Nakomis mine; B, Susquehanna mine. _____ .. __________ ....... _______ ......... 68 

XX. A, Bear Hill mine; B, Beulah mine ________ .. __ .. ____ • __ ......... ______ . ____ .. __ 70 

XXI. A, Climax mine; B, Morning Star mill, connected with mine above by gravity 

tram _ . ___ .. __ .. ___________ . ____________ . ___ .. __ . _______ .. _ .. _ . _______ .. _ _ _ . _ . 72 

XXII. View of Rush post-office and Morning Star mine and mill _________ . ____ . __ . ___ . _ 72 . 

XXIII. A, East end of main cut at Morning Star mi~e, showing fissure opposite end of 

track; B, Mcintosh mill, connected with mine above by cable' tram __ .. ___ . _. _ _ _ _ 74 

XXIV. Mcintosh mine, Rush, Ark., showing natural exposure of rocks somewhat 

obscured by waste from the open cut. ___ . ____ .. __ . _________ _ .. _. _. _-. ______ ... 74 

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10 ILLUSTRATIONS. 

Page. 

PLATE XXV. A, White Eagle mine; B, Red .Cloud mine. _____ .-------_ ____________________ 76 

XXVI. A, Open cut, Hulsenbeck property; B, Fissure and shaft house at Baker and 

McGrath mine. _______ ._ .. ___ . . ..... __ . ____ . ___ ._ .... .. . ___ .. __ . _. ________ · 78 

XXVII. Spier mine, sinking shaft in fault breccia ...... _ ..... ___ . .. _________ .. ______ . 82 

FIG. 1. Generalized section through the zinc and lead district, showing geologic relations of 

ore-bearing horizons and former extension of formations which have been removed 

by erosion _ . ___________________________________________________ . _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ 32 

2. Diagram to show how stress may produce differential movement and brecciation 

as a result of variation in the character of the rocks acted upon ......... _ _ _ _ _ _ _ 33 

3. General structural section showing relations of the Ozark region to the Arkansas 

Valley and Ouachita Mountain regions ....... _ .. __ .. __ .. _ -.. ___ . . . . . . . . . . . . . . . . . . 34 

4. Section across Rush Creek fault near _Rush post-office .. ___ .... _.................... 36 

5. Section through Pilot Mountain showing Pilot Mountain fault. _____________ . _____ .. 37 

6. Section across St. Joe fault and monocline, St. Joe, Ark .... ~_ ..................... _ 38 
LETTER OF TRANSMITTAIJ. 

DEPARTMENT OF THE INTERIOR, 

U . .S. GEOLOGICAL SuRVEY, 

Washington, D. C., 2Vovember 24, 1903, 

SIR: I have the honor to transm1J herewith the manuscript o£ a report on 

the zinc and lead deposits o£ northern Arkansas, by George I. Adams, assisted by 

A. H. Purdue and B. F. Burchard, with a section on the determination and correlation o£ formations, by E. 0. Ulrich, and to reeommend that it be published 

as a professional paper. \ ' 

The report covers the whole o£ the Yellville quadrangle, £or which a geologic 

£olio is in preparation, together with portions o£ three adjacent quadrangles. It 

describes an important lead and zinc . producing region which is rapidly increasing in importance, and it is. oelieved that this description o£ the geological 

occurrence and origin o£ these deposits will be o£ material assistance ii1 its economic development. 

Very respectfully, C. V\T. HAYES, 

Geologist in Charge of Geology. 

Hon. CHARLES D. WALCOTT, 

Director, United States Geological Survey. 

11 

ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

By GEORGE I. ADAMS, 

Assisted by A. H. PuRDUE and E. F. BuRCHARD. 

INTRODUCTION. 

Scope of this report.-The field work on whieh this report is based was 

carried on during the months of July, August, and September, 1902. The writer 

was assisted by Prof. A. H. Purdue, of the University of Arkansas, and Mr. 

Ernest F. Burchard. The larger portion of the time was used in the detailed 

examination and study of the Yellville qua&rangle, which is between parallels 36° 

and 36° 30' and meridians 92° 30' and 93° , and embraces Marion County, the 

northern border of Searcy County, the eastern border of Boone County, and the 

northeastern corner of Newton County. The adjacent country, which is usually 

recognized as mineral bearing, was examined in a general way. Mr. E. 0. 

Ulrich was in the field two weeks collecting fossils ~nd studying the rocks for 

the purpose of correlation, and Dr. George H. Girty devoted a week to a p.ortion 

of the section in an adjacent area. 

The stage of development of the fielQ. is such that the report is in a sense a 

preliminary one, as few of the ore bodies have been worked sufficiently to determine their extent. There , are many openings and prospe.cts and a few (>roducing 

mines. The examination of the prospects consumed much of the time, and 

although the information obtained from them was valuable as indicating the position 

and manner of occurrenee of the ore bodies, it was often unsatisfactory because 

the openings were of limited extent or had been made so long ago that they 

were covered with debris. Only a few of the mines which have underground 

workings were accessible, since most of them were idle and filled with water. 

Historical sk tcl~.-Lead ore was discovered in northern Arkansas by the 

early explorers and pioneers, and smelted by them in a crude manner, in order 

to obtain lead for rifle bullets. Schoolcraft, who passed through the region in 

1818, mentions, in the account of his explorations, the occurrence of lead in 

northern Arkansas, and Featherstonhaugh in 1834 reported that a mine had been 

13 

. ; 
• 

14 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

opened on Strawberry River. No attempt appears to have been made to produce lead in commercial quantities until in the fifties, when ore was smelted in 

the vicinity of Lead Hill. There was a revival of the industry in the seventies, 

but the cost of transportation was_ so great that the smelters, a£ter operating for 

a year or two, were abandoned. 

In early times zinc ores seem to have attracted no attention, as compared 

with lead ores, probably because they were not so well understood. A zinc 

smelter, however, was erected at Calamine, Sharp County, in 1857, but the company ceased operations at the outbreak of the civil war. In 1871-72 smelting 

w~s again attempted at this place, and was carried on for a short time. Prospecting for zinc ores began about 1886. The ores _are so generally distributed 

and so readily accessible that the region attracted the attention of' mining· men and 

investors, and in 1899 there was what might be called a rush into the field. 

Lirnits of the northern Arkansas district.-The principal development of zinc 

and lead mining in northern Arkansas is in Boone, Marion, Baxter, Searcy, and 

Newton counties. The mines and prospects shown in Pl. I indicate in a general 

way the extent of the district. In addition there are some prospects to the west; 

and mining has been carried on at a few localities to the east, in Lawrence, 

Sharp, and Independence counties. The ores at these places are known to be 

similar to those of the area here described, but they are not. discussed in this 

report. 

Transportation facilities.-Until recently no railroad reached the field. Traveling was by means of stage. The route usually pursued was from Eureka Springs, 

a railroad point, eastward about 50 miles to Harrison, thence eastward 30 miles 

to Yell ville; or from West Plains, Mo., a railroad station about 70 miles northeast of Yell ville. The country is rough and the roads stony, so that traveling 

and transportation are difficult. Nevertheless, mining claims were developed and 

mills erected before the railroads had been. extended into the field. It was 

thought that White River, which is navigable for small boats, would furnish an 

outlet for the ore, but the necessity of hauling and the uncertainty of sufficient 

water caused the abandonment of this route after a few shipments had been made. 

In 1901 the St. Louis and North Arkansas Railroad was built to Harrison from 

' Eureka Springs, and since that time has been extended southeastward to Buffalo 

Fork of White River. It is proposed to further extend this road, by way of 

Marshall, southeastward in the direction of Little Rock. 

The Missouri Pacific Railway has begun to build a line from Batesville, 

along the valley of White River, to Buffalo. From this point it will pass by 

way of Yellville, and thence northwestward into Missouri. This, line will be in 

operation to Buffalo some time before the close of 1903. 
LEGEND 

C..A.R BON I FERO US 

----·---'---MISSiSsIPPiAN' 

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l'rtllrriJolly (f ,,. HorJnt! lbJ7n<(linn~ 

ORDOVICI A 

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'<' :'>litH's tllld pi'O:p<'<' t~ ---- P1·intipal fnu lt s 

R 22 W R.21 W. 

R.20 W 

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,' 110\Vl.:-;C. <;J· ::\I': l / \1 (; J·:OLOGY , ~I PF J~( IJ>\1, ~11.;\P:S .. \. 1) PI 

0 

= 

. t>J•:CT. ' 

Complied by George I Adams 

rom detc. tl ed su•·vey of th e 

Yellville quad angle and maps of t e Ar l<ans as Geologicnl Su ey 
INTRODUCTION. 15 

The completion of the railroads will afford facilities for shipping ore, so 

that mines which have not been able to operate will probably· begin work. 

Others~1 which had until recently attempted no dm elopment beyond prospecting 

for ore, are already erecting mills or more definitely determining the character of 

the ground preparatory to doing so. Although few of the mines are situated 

near the railroads, the distances which the ores must be hauled will be so lessened 

that the product can be marketed profitably. With the development of the 

mines railroad spurs and branch lines will probably be built, and the field can 

assume its true commercial importance. 

Production o.f the district.-From the information contained in published 

reports and gathered by inquiry it has been estimated that the output of the 

northern Arkansas district up to and including the year 1900 was 1,500 tons of 

zin~ ore and 500 tons of lead. In 1901 about 500 tons of zinc were marketed; 

and in 1902 about 1,000 tons, or double the amount of the previous year. The 

production of lead during 1901 and 1902 was unimportant. There is considerable 

ore now stored in the bins awaiting transportation facilities, and the production 

of the district proJ:nises to increase during the coming year. 

Prospective development.-The question which is of most interest at the present time is, vVill ore bodies in northern Arkansas warrant operations on a large 

scale? It is hoped that what is said in this paper will throw some light upon 

the question, which is a difficult. one to answer in the absence of the ' extensive 

development of any of the mines. What has been done thus far in the way of 

mining is not a true criterion for the field. Some of the companies which have 

been organized have been promoted by men inexperienced in the production of 

zinc and lead. The expenditure of money in erecting mills and bringing in 

machinery, which it was- necessary to haul a long distance~ and the failure to 

market ore at a profit~ because of the absence of transportation facilities, usually 

has been followed by the suspension of operations. Moreover, the ore deposits 

in northern Arkan~as are not such as mining men generally are familittr with, 

and some have been misled by the 'results of their prospecting, since they judged 

that the ore bodies would continue similar to those of other fields. Finally, 

although certain of the mines have produced clean ores, the surface workings 

have usually resulted in the finding of mixed ores, which are difficult to market 

in a satisfactory manner. With the continuance of deeper workings and the 

following of ore bodies into the hillsides this difficulty is disappearing. 

While it is impossible to predict with certainty the future of the field, there 

are certain of the mines now opened which are capable of a large output, and 

many of the prospects· warrant further exploitation. 
16 ZINC AND LEAD DEPOSITS OF NOR'.fHERN ARKANSAS. 

SURFACE FEATURES. 

General character.-Northern Arkansas is a hilly region, although to one who 

travels through it the amount of relief is not clearly apparent, since the timber 

nearly everywhere prevents a broad view. The streams have cut into the rocks 

so deeply that in their lower courses they may be appropriately considered as 

flowing through canyons. The walls of the canyons are usually steep on one 

side and have a gradual slope on the other. The main streams are tortuous, and 

the tributaries dissect t&e country into ridges having a dendritic arrangement. 

The best roads follow the divides or the stream valleys, and the roads which are 

divergent from them are usually so rough as to make heavy hauling impossible. 

Because of the broken nature of the country the soil forms a thin mantle over 

the rocks, except on the more level uplands or in the narrow alluvial valleys. 

The larger portion of the land is not suited for farming, because it is very 

stony, or becomes so soon after it has been cleared and cultivated. Agriculture 

is at present the principal industry, but its development · will be limited by the 

nature of the land. Fruit raising, on the other hand, promises to be entered 

into more largely. The hillslopes are suitable for orchards, and the climate is 

particularly favorable. 

Dissection of the country by streams has exposed considerable thicknesses 

of the rocks in such a way as to render the mineral contents of the upper horizons' easily discoverable. The rough topography, however, is unfavorable to the 

building of numerous railroads and the hauling of the output of ore to shipping 

points. Every part of the country could be rendered accessible by the construction of wagon roads, as there is an abundance of good material for both roads 

and bridges .. 

Physiographic relations of the Ozark Plateau and Boston Mountains.-The 

zinc and lead mining district lies in what is known as the plateau portion of the 

Ozark region. This region embraces southern Missouri, the northeastern corner 

of Indian Territory, and northern Arkansas. Its drainage and topography are 

shown on the accompanying 'sketch map (Pl. II, A). The Ozark Plateau lies north 

of the Boston Mountains, which extend from Batesville, Ark., westward nearly 

to Muscogee, Ind. T. The northern border of the Boston Mountains presents 

an irregular escarpment, which is seen to the south of the zinc and lead fields. 

They are composed of a series of sandstones and shales, with some limestone beds, 

which erosion has cut into flat-topped spurs and peninsular-like ridges; between 

which are the stream valleys. The northern extremities of the ridges stand out 

as conspicuous points or promontories, from which may be obtaineQ broad views 

of the plateau country. 
U.S. GEOLOGICAL SURVEY PROFESSI ONAL PAPER NO. 2 -4 ? l. II 

95" 

SKETCH MAP OF THE 

38 25 

('_,ontour interval 250feet. 

l903 

95° 94" 

(A) 

95° 90" 

SKETCH MAP 

OF T HE 

OZAllK R_EGION 

Showing physiographic features 

BY GEORGE I .ADAMS 38. Scal e 25 25 

1903 

\ I 

(B) JULIUS BIEN & CO . N Y. 

U. S. GEOLOGICA L SURVfY PROFESSIONAL PAPER NO. 24 PL. Il l 

A . ESCARPMENT OF HALLS MOUNTA IN. 

Seen from the no rth, 5 m il es distant, ar.ross Crooked Creek Valley. 

B. BOTTOM LAND ALONG WHITE RI VER NEAR GASVILLE. 

Looking northwest from mountain east of De mton's ferry. 

SURF ACE J1'EA':tURES. 17 

Division~ of the Ozark Plateau.-When seen in a broad view the irregularities 

of the plateau country are largely softened by the mantle of forest, and as the 

higher points rise to practically the same plane the plateau has a rolling or 

billowy appearance. There are, however, two divisions .which are apparent i'n 

the landscape at many points and are found to be related to the rock forma-.· 

tions wherever the field is studied (Pl. II, B). Between them there is an abrupt 

change in elevation of about 300 feet, known as the Burlington esca~pment. ·(See 

Pl. III, A.) . The higher region west of the escarpment is called the Spriqgfield 

upland. It has its typical development in south:western Missouri, around 

Springfield, from which place it was named. Its extension in northern Arkansas 

is a narrow, irregular upland lying at the foot of the Boston Mountains. The 

larger areas of its unbroken surface form the farm lands in what is known as 

the chert country of northern Arkansas, and the rock which ·underlies it is the 

Boone limestone and chert. Its extent accordingly corresponds with the area of 

this formation shown on the accompanying map (Pl. I) _ 

The Salem upland is developed upon · the Yellville formation; which consists 

of' dolomitic J.imestones, which form the country rock over the re~aining portion 

of the plateau in northern Arkansas. It does not show its typical development 

in the mining district, however, since the valley of White River and the numeroq_s tributaries of that stream give it a decidedly broken character. In southcentral Missouri, around Salem, from which this division was named, it has ~ 

more even surface. However, th~ horizon line as viewed in n9rt~ern Arkansas 

is found to be almost even, and it is readily seen that the higher points fall in 

t4e same general plane. 

LowlancM.--Inasmuch as the two principal divisions have been discus~ed a~ 

uplands, it is natural to infer that lowlands exist, whic~ .are i_n contrast to them. 

This stage_ of physiographic development of the region is relatively .recent. The 

streams have not had sufficient time to widen their valleys, and their work thus 

far has been confined to cutting them downward. Her~ and there, howe.ver, 

on the larger ones are found narrow, crescentic bottom lands, whi9h occupy the 

inner side of the bends of the stream (Pl. III, B). vVhat are now the uplands 

were in the previous period relatively low-lying plairls, through which the streams 

flowed in shallow valJeys, a_nd the canyons of the present time owe their tortuous 

courses . to the sinuosities of the former <J.rainage, which· h.ave been aceentuated 

during the process of downcutting. 

Previous surface features.-In discu~sing the geologic ;history of the zinc and 

lead . district, it is nec~ssary to reconstruct in a measure the conditions of the 

land surface which existed previom:; to_ the development of its present topography. 

4538--~o. 24--04--' .--2 

; 
18 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

An idea of what the cou,ntry was probably like may be obtained by imagming 

the present valleys ~n the Salem upland filled to a . level with the bluffs of the 

streams. If the upper course's ·of the streams we're filled in a proportionate 

manner, tbe Burlington escarpment would still remain as a conspicuous feature, 

but the valleys'. within the Springfield upland would be less sharply incised. 

'Vhat is now the Salem upland would be practically a lowland, and the Springfield upland would rise. approximately 350 feet above it. The extent of the 

Springfield upland, however, would be somewhat greater than at pr~sent, and-its 

border much less dissected, since in the proces~ of the downcutting of the streams 

it has suffered extensive degradation. 

It has been remarked concerning the northern Arkansas field that a large 

portion of the rocks which are mineral bearing have been carried awar by the 

work of t~e streams. This undoubtedly is true, and an estimate of •the amount 

may be formed by some such process of reasoning as has been outlined apove. 

The ore-bearing rocks, however, which have been remov~d during the erosion of 

the stream valleys constituted but a small percentage of what still remain above 

the grade of White ·River, which has the deepest valley in this area. The slopes 

and hillsides which have resulted from the downcutting render the ores accessible 

and multiply._ many times the exposures of individual ore-bearing beds. 

DESCRIPTION OF GEOLOGIC FORMATIONS. 

The formations described in this report have been mapped in detail within 

the limits of the Yellville quadrangle. -Pis. IV and V, show the northern and 

southern parts of this area, respectively. On these maps the positions of the 

important mines· and prospects are shown by crossed hammers. 

Some of the formations are so thin that it is difficult to show them in their 

correct importance, but in the field they can be recognized if careful attention is 

given to the following descriptions of their character and thickne~s. For the 

purpose of setting forth the entire geologic section other lo~alities have been 

visited and the relations of the formations studied and described. 

ORDOVICIAN SYSTEM. 

Yell/ville formation.-This name, Yell ville formation, Is applied to the mag·-· 

nesian limestoiies, or dolomites, of Ordovician age, which constitute the principal 

lead- and zinc-bearing rocks of northern Arkansas. They are of wide occurrence 

in the district, especially in Marion and Baxter counties. They are th~ oldest 

rocks exposed in northern Arkansas, and have been described in various preceding · 

reports as belonging to the m'lgnesian-limestone series. The base of the section · 

is not exposed, and the total thickness can be estimated only from the record 
U.S.GEOLOGICAL SURVEY 

1 93"oo' R. t9;. 36o_ - --,;r-~__,.t:n'"t::llll"r~-.:.-,- ;---.;;:-:-, 

130' -

Henry Gannett Ch•c Topographer 

Jno H Rensh we. Geographer in cha r0 P. 

Tn ngulat.on by Geo i . Hawk1ns 

Topog1aphy by H B Bla•r 

Sur v yed 1n 1891 

R . 16 W. so ' R . 17 W. R . 16 W. 

GEOLOGI C ;\f\P OF 'fill•: ~OHTJlFH~ P1\Hrl' OF Till·: 

YEJJLVlJ.J J·~ , AllK., ()t~l\J)H \:\TC,-L1 ~ 

Conlo tu · intf'n·HJ .')() fC<' L 

!)rt.(U.IIr W· nuYut ,)' ("(t (("t·c'{ 

s rnil l'S 

-----

PROFESSIONAL PAPER NO. 24 PL . IV 

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ORDOVICIAN ROOKS. 19 

· of a deep well which was drilled at Cushman, near Batesville, and which passed 

through 1,515 feet of strata without reaching the pre-Cambrian crystallin~ . The 

age of the rocks in the lower part of this wel1 is not definitely known. Judging 

from the exposures around the baRe of the St. Francis Mountains in southeastern 

Missouri the rocks encountered in the well may range downward into the Cambrian. The Yellville formation is intended to include only such as are of OrdoVIcian age. Along White River the natural exposures of the Yellville formation 

approximate 500 feet (Pl. . VI, A and B). The limel;ltones vary from massive to . 

thin-bedded strata, with intercalations of shaly material and well-defined shale 

beds. A section described in detail at any particular locality would probably 

not be found. repeated in another part of the field, since the . rocks vary in their 

lateral extent, the beds . grading from one phase into another, according to the . 

local conditions of sedimentation which prevailed at the time of their deposition. 

The rocks appear to have been laid down in relatively shallow seas, since mud 

cracks or sun cracks can be observed on exposed surfaces here and there, and 

the uneven bedding and change in texture indicate the action of currents; and 

appa1:ently in some .places the scouring of a sea bottom. The limestones, where 

they are- not weathered, have a dense structure. Their color varies from gray to 

dark blue and chocolate brown. Their composition indicates that many of the 

beds are true dolomites, since they contain the accepted theoretical proportions 

of calcium carbonate and magnesium carbonate; but with the variation ih lithology 

other constituents are found, such as clayey material similar to that of the shales 

into which they grade, and sand grains similar to the material which constitutes 

the saccharoidal sandstone which is described on a later page. 

Where they present an argillaceom; phase they exhibit laminations in which 

the thin :films of clayey material indicate bedding planes. Not infrequently they 

are rich in organic matter, which . gives them a dark appearance, and in some 

cases a decidedly fetid odor. The sandy phase of the dolomite locally manifests 

itself in the lower portion of the ::-;eries, and in the higher portion there are 

some beds which have the character of sandstone: The clear, rounded grains of 

sand which are found distributed in some o£ the dolomites give them upon 

weathering somewhat the appearance of sandstones, since the calcareous material 

dissolves out. Where the exposures are unweathered the true nature of the rock 

is readily discernible. · In other portions of the Ordovician sea, conditions were 

favorable to the extensive deposition of sandstones. Their local development in 

northern Arkansas recalls the so~called second, third, and fourth saccharoidal 

sandstones of the Missouri section as described by Swallow. One of these local 

beds of sandstone is exposed along the valley of Clear Creek. It occurs from 
20 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

50 to 75 feet below the top of the formation, and has a variable thickness, averaging 

about 20 feet. Throughout the remaining portion of the district it is impossible 

to identify this horizon. In the vicinity of Cowan post-office and in the country 

to the south for 2 or 3 miles there is a similar sandstone which is exposed at 

many places and gives rise to a sandy soil. Other beds were noted which are 

but a few feet in thickness and seem to have only a limited extent. 

The bedding of the dolomites of the Yellville formation exhibits a peculiarity 

which may be described as sagging and thinning. It is apparently due to the 

unevenness of the floor on which the sediments were laid down and to the variatjon within short distances of thickness of . the material deposited. As has been 

suggested above, 0urrerit action may account for the phenomena to some degree; 

possibly, also, unequal .. settling and squeezing of the material took place before 

consolidation. This structure has the appearance of local unconformity in many 

cases, and is interestingly exhibited in the frequent nearly vertical exposures along . . I . 

the stream valleys. 

The ore bodies contained in the dolomites are related to structures and secondary phases of the rock, which will be more fully described in another part 

of this paper, in connection with the question of ore deposition. They may be 

stated to be characterized by fracturing, jointing, brecciation, and faulting, which 

are the result of · mechanical · conditions and of solution, cementation, reerystalliza: 

tion, silicification, and replacement, which have been brought about by the circulation of ground water. Certain of the chemical changes · have taken place so 

extensively' and are manifested in the rocks independent of ore bodies, that they 

should appropriately be described here. The effect of solution has been to produce a cellular structure in certain of the , beds, and these openings, as a result 

of subsequent deposition of silica, have the form of quartz druses. Not infrequently the dolomites; which contain a considerable amount of sand or have been 

largely replaced by silica, grade into a quartzitic phase. This seems to be more 

frequent in the lower portion of the ·section, and has been noted by the various 

geologists who have described the rocks as quartzites. The Yellville formation 

carries considerable quantities of chert, or flint, as it is sometimes called, which 

occurs as nodules and lenses. The chert of this formation may usually be distinguished by the fac·t that it has a white-a;nd-black concentrically banded structure, 

K ey sandstone.- The Key sandstone, which is named from the post-office of 

Key, in the valley of White River, northeast of Fayette~ille, is the rock most 

conspicuous and valuable to mining men as a datum in this district. It occurs 

usuaJly as ledges or benches, and is locally known as the sand ledge or sand cap 

(Pl. VII, B). The rock is· what is known as a saccharoidal 'sandstone, this name 

being applied because of the fact that when it is struck with a hammer it 

/ 
U.S GEOLOGICAL SURVEY 

Henry Gennett, Ch tef Topographer 

Jno H Renshawe, Geographer in charge 

Trtangutat•on by Geo i Hawkins 

Topography by H B Blai,r 

Surveyed •n 1891 

.Dauvn i.s m.car Jea, le•·el 

l9 0J 

JULIUS BIEN &CO, UTH. N.Y 

Til E 

PROFESSIONAL PAPER NO. 24 PL. V 

Geology by Oe or~e I. Ad a ms 

a'ssiS1ed by A. H t:Su rd ue 

and E F. Burchard 1902-03 

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ORDOVICIAN ROOKS. 21 

crumbles into a fine white sand, very similar in appearance to granulated sugar. 

The outer surface of the stone usually has a brownish appearance, as a result of 

the iron oxide which occurs as a coating upon it. When it is broken it exhibits 

a very even structure, the individual gra~ns being of almost uniform size. Occasionally, where it is unweathered, small masses of pyrite C3ccur in it, and it has 

a water-green color. When weathered the green color disappears and the pyrite 

is' oxidized and transferred to the surface, forming a ferruginous coating. The 

ferruginous stain is also e~hibited in the bedding planes. 

The . thickness of the strata varies from a · few inches to sever~l feet, and the 

character of the bedding is liable to change materially in a short. distance. It not 

infrequently exhibits ripple. marks and false bedding. Its weathered surfaces have 

a peculiar ;rounded appearance. The ledges are beveled, so that the · layers have 

fluted edges. At the · heads of ravines the sandstone not infrequently :forms a 

water:fall, and the ledge is undermined in the process of erosion. Where it 

occurs along the canyon walls it is rendered conspicuous by the scantiness of 

·the vegetation. On the hillsides it gives rise, up~m weathering, to a sandy soil, 

and a few of the abandoned :farms which are seen in this section of the cou'ntry 

are located upon its outcrop. When the land is new and . . rich in · humus which 

has accumulated under the protection of vegetation it' is fertile; but after being 

cultivated for a few years the land washes badly, and the 'increased sandiness 

renders it poor :farm land. 

The conditions under which this sandstone was deposited appear to have 

been those o:f shallow water, in which the quartz sand was worn into more or 

less rounded grains. In the southern part · of the district its marine origin is 

attested by the presence in it of a vertical structure known as Scolith1.ts, ·which 

is due to the tubes f~rmed by sea worms. Fucoidal markings. are also :found. 

The pitted appearance o:f t{le upper portion of the sandstone at many places is 

due to the occurrence of the scolithus, which causes it to weather unequally. 

The thickness o:f the sandstone varies from a few feet to over 100 :feet, and is 

apparently d~e in part to conditions of deposition and in considerable measure 

to subsequent erosion. 

· The Key sandstone, because of its conspicuousness, IS a convenient datum 

for determining the horizon at which the ore deposits occur. It is not an orebearing formation, although when ore bodies are found immediately below it 

the:y occasionally reach up into the lower portion of the sandstone . 

. Izard Umestone.-The Izard limestone, which is named from Izard County, 

where it has its greatest thickness, extends into the southern portion of the zinc , 

and lead district,_ and where present it immediately overlies the Key sandstone. 

Its greatest thickness reported is 240 feet, but in the area here described . it 
22 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

seldom exceeds 100 feet, and thins down gradually on its extreme borders so 

that it can scarcely .be found, and finally disappears from the section. This · 

thin~ing is apparently due to the erosion . of its upper surface. The rock is a 

bluish-gray limestone, having a very dense structure, and is difficult to break 

under the hammer or to work for building material, since it is what is called 

"plucky." The rock is seldom fossiliferous. The few indications of remaips 

which have been geen in it are calcite casts, which appear as lines when it is 

broken. The base of this formation shows a tendency to grade into magnesian 

limestones and occasionally sandy beds. Although this forma\ion can be identified readily by one who is familiar with it, where it is thin, as in the southern 

portion of the mining disttict, it is often unnoticed, since its weathered surfaces 

resemble the dolomites. In so far as . has been observed it is not the seat of 

miner~l deposits, and the few openings which have been made in it by prospectors give little encouragement for further work. Occasionally, however, 

where it is fra.ctured it carries some pink spar, and it is not impossible that it 

is in some d.egree mineral bearing. 

· Polk Bayou limestone.-This fo:~;mation, which when it is present in the 

field, occurs just above the Izard, differs materially from the rocks heretofore 

described. It has a coarsely crystalline structnre and usually when freshly 

broken a slightly pinkish tinge. ' It consists of massive beds, and has a re!llarkably uniform texture throughout. The area of its occurrence in the Yellville 

quadrangle is very limited, its outcrop being confined to mi.rrow exposures in 

the southern part of the field. It does not occur as extensively as the Izard 

limestone, and its section is variable, seldom exceeding 15 feet. Its thinness in 

this area appears to be the result of the erosion of its upper surfaces. It is 

typically repres~nted in Independence County, north of Batesville, on Polk 

Bayou, frorri which locality it is , named. 

Its presence in the field here described is significant in the geologic history 

of the area, but it has no importance as a miJ?eral-bearing rock. Because of it_s 

uniformly . crystalline structure it bas been described as a marble in the 

Arkansas State reports. It bas some value for. building pn:rpo'ses, but thus far 

is not used commercially. 

DEVONIAN SYSTEM. 

Sylamore formation.-The Sylamore formation consists principally of a , sandstone bed, and was named from a ·eek in Stone County, where it is well 

exposed and bas a maximum thickness of 40 feet. It has associated with it. a 

bed of shale. The relation of the sandstone to the shale has not been definitely 

stated in previous reports. Wherever the formation has been found in the 
ll . S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. VI 

B ENGLES BLUFF, NEAR SYLA MORE, IN IZAR D CO U NTY, ARK. 

DEVONIAN SYSTEM. 23 

Yellville quadrangle, the sandstone lies above the shale. Its maximum thickrie~s 

is about 7 feet, and the shale below it does not exceed 15 feet. 

The sandstone consists of rather coarse quartz grains, which have been rounded, 

and, except for the Hize of the · grains, the rock resembles the saccharoidal 

sandstone in a general way. 1 The Sylamore sandstone thins so that in some places 

it is not represented 1and in others occurs only as variable, lens-like masses· or 

sandy beds in the upper part of the shale. The shales, where they are thickest, 

as at the exposure on Dry Creek; 1 below Duff, are rather uniform in character 

and have a greenish color. ·Where the sandstones and shales , are variable, as is 

the case just north of St. Joe, the color is darker, often nearly black, and the 

formation contains a notable amount of phosphate pebbles, which are frequently 

embedded in a sandy matrix, g·iving the rock ar conglomeratic appearance. The 

pebble~ are sparingly represented at qther exposures, but the phosphatic material 

seems to be more abund!lnt where uneven bedding and variable conditions of 

sedimentation have occurred. The phosphate pebbles when unweathered are black, 

hut on exposed surfaces they are yellowish or brownish. They vary in size 

from very small ones up to the size of walnuts, ·or even larger. They have a 

waterworn appearance. 

The relation of the Sylamore sandstone to the lower rocks is plainly exhibited 

in the bed of the stream southeast of Duff. The Sylamore there rests upon 

\ 

the Polk Bayou limestone, and the surface of the limestone bas been exposed by 

erosion so that the irregularities of its surface, which were produced prior to the 

deposition of the Sy lam ore shale, can -be seen in the creek bed. It is potboled 

and pitted and worn , into channels. In these depressions remnants of the shale 

and the contained pebbles may he seen. Thus far, at ; all the outcrops of the 

Sylamore which have been visited it rests upon the .Polk Bayou Iime'stone. It 

has a more limited geographic extent than that formation, and the sedimentary 

basin in w~ich it was deposited appears not to have extended west of the Yellville 

quadrangle. 

The ag~ of this formation has been in dispute. Fragments of large fish bones 

have been found embedded in the sandstone, and these are considered as indications 

of Devonian age. Aside from these remains some invertebrate fossils occur, which 

tend to corroborate this view. The confusion which has previously existed in the 

attempts made to classify the Sylamore formation has arisen from the fact that 

an effort has been made to correlate it with the Noel shale (described as the Eureka 

shale in the Arkansas reports), which occurs farther west. There is, however, an 

intermediate region, approximately 30 miles in width, in which neither of these 

formations is represented. The reason for associating the, Sylamore formation 
. I 

24 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

with ·the Noel shale seems to have been that they are both succeeded by the St. 

Joe member of the Boone and the shales are somewhat similar. 

Although the phosphatic .J?ebbles of the Syhtmore are locally sparingly represented in the lower few inches of the St. Joe member of the Boone, there was 

a break in sedimentation between the formations, and the pebbles have found 

their way into the St; ;Joe as a result of the reworking of the lower beds. In 

the case of the Noel shale there is a gradual transition from the shales · to the 

limestones, and an interlarding of the tlhales in the lo~er beds of the St. Joe at 

some localities in such a way as to intimately connect them. 

It is a surprising fact that Devonian sediments should be so sparingly 

represented in this . region. During the Devonian interval the older rocks were 

largely subject to erosion. It was at this time that the ~eveling of the Polk 

Bayou, Izard, and · Key formations took place. Probably the Yellville formation 

also suffered c~nsiderable thinning at some localities.· The Sy lam ore formation 

may be a 1~emnant of thicker deposits which accu~ulated during the Devonian 

period, but more likely it 'represents a marginal deposit in an encroaching sea. 

The fact that it contains phosphatic material and sandstones composed of rounded 

quartz grains is favorable to the latter theory. The shale probably represents 

the mud, and the peb~les ~he estuaria! accumulations of phosphatic nodules which 

were deposited in some ·such way as were the pebble phosphates of the Charleston 

phosphate region, in South Carolina, where the phosphate is obtained by dredging 

iri the mouths of rivers. 

CARBONIFEROUS SYSTEM. 

MISSISSIPPIAN SERIES. 

Noel shale.-The Noel ·shale .has been previously described by the Arkansas 

State survey under the name of "Eureka shale;" but . this name is preoccupied 

by the Eureka quartzite of Nevada, and accordingly it has been renamed, from 

the tow~ of Noel, in southeastern Missouri, where it has been studied . and at 

which place it is typic~lly exposed. It consists of a bed varying from a few 

feet, and in some cases a few inches, up to 70 feet in thickness. } usually it 

averages from 15 to 30 feet. Its color is often black, although not infrequently 

it has a. greenish, and sometimes a yellowish, appearance, according to the condition of weathering or the amount of carbonaceous material contained in it. Thus 

far it has nevE<r been found lying on the Polk Bayou limestone, as does the 

Sylamore. It commonly rests on the Key sandstone, or in case that ·formation 

is absent, as a result of pre-Carboniferoug erosion, it rests on the Yellville 

formation. In its upper part it contains at some places thin, limy layers, and 

when not abruptly succeeded by the even~bedded St. Joe member of the Boone 

formation, it grades upward into that formation, thin layers of shale being found 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. VII 

• I A. LEDGE OF ST. JOE LI M ESTONE. 

CARBONIFEROlJS ROCKS; 25 

between the beds of , limestone. The Eureka shale is not known to carr:..y phosphatic material, nor has it thus far yielded bones of fishes. The areas in which 

it outcrops are to the west of· the zinc and lead district and ,are widely separated 

from the Sylamore, and there appears to be no reason for any longel' confusing 

it with the Devonian. The fossils which it has yielded a·re of Carboniferous age, 

and it probably represents the muddy sediments deposited in the encroaching 

Carboniferou's sea. 

Boone Umestone and chert.-The Noel shale is succeeded by the Boone formation, which appears to be conformable with it, and represents merely a ~hange 

in the character of sedimentation. Over a large area its basal member is an evenbedded limestone, free from chert and showing in a distinct ledge (PI: VII, A), 

sometimes shelly and thin bedded. It is known as the St. Joe limestone member. 

Its thickness in northern 'Arkansas varies from a few feet up ·to 50 feet. · At 

some places. it is difficult to distinguish, because of variation in character and its 

resemblance to the overlying rocks. It has been thought to be absent at certain 

localities in the Yell ville quadrangle, but careful search has resulted in finding 

it at these places. Its upper beds are often full of crinoid stems, and, although 

it contains other fossils, . they are not abundant. It is usually of a soft-gray 

color, and when freshly quarried often has a bluish cast. In the zinc and lead 

district, particularly at St. Joe, from which locality this member is named, it has 

a reddish appearance and a chocolate-brown color on fresh surfaces. The red color 

is due to the presence of iron. Where water has circulated thr<?ugh the beds 

the rock has a variegated appearance, being changed to a greenish color. Within 

the field here discussed it has been noted that sometimes a portion .of the ledge 

is red and the remaining portion grayish. The area within which the red color 

prevails is to the south, around St. Joe. This rock has been described as a 

marble by the Arkansas State survey. It will take a good polish, but it is 

questionable whether it will ever be of economic importance as an ornamental 

stone, since it does not occur in suitable size~ The rock is often favorafil}' 

exposed for quarrying. Where it is underlain by a , shale the weathering of the 

soft material causes the ledge to jut out and eventually to break down into 

large slabs and blocks. Upon weathering it sometimes forms isol~ted columns. 

Usually the abundance of. chert from the overlying portion of the Boone forma- . , 

tion disguises its outcrop. 

The remaining portion of the Boone formation consists of beds of cherty 

limestone and beds of chert, which vary in their lateral and vertical extent in 

such a way that it has been impossible to divide this part of the formation into 

members which can be generally recognized. The thickness of the formation is 

about 325 feet. The country in which the Boone formation occurs is distinguished 

• 
26 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

I 

by the presence of chert, which -is . seen in exposures and is left upon the surface 

by the weathering of the limestones. As the result of the slow dis_integration of 

the chert the hill slopes are covered with it and the valleys of the minor streams 

are :floored with it to a considerable depth. The perpendicular bluffs are the 

only outcrops which are not more or less disguised· by this residual material. 

When first exposed the chert is compact and has a light-gray or bluish color. 

Upon weathering it becomes yellowish brown, being stained by iron, and the 

fragments are often very · light and porous. The fragments of flint form a 

natural macadam for the more level roads of the country in which this formation 

occurs. 

The limestones of the upper portion of the Boone formation are often 

coarsely crystalline, and usually have a light-gray color. They contain· numerous 

well-preserved fossils, but crinoid stems are perhaps the most conspicuous. The 

even beds form a valuable quarry stone, a.nd when free from chert can be burned 

for lime. Exposures exhibit the limestones as heavy-bedded r~cks free from 

chert, as thin-bedded limestones interstratified with layers of chert, or unevenly 

bedded with lentils and rolls of chert. Generally the upper portion of the formation is heavily bedded, and the lower portion contains the larger amount of flint. 

The line separating the St. Joe member from the remaining portion, although not 

marked by any very evident stratigraphic break, has been drawn at the point 

where the chert appears, and is at a definite horizon. 

Moorefield shale.-In the vicinity of Batesville there is a bed of shale lying 

upon the Boone limestone and chert. It is well exposed around Moorefield, from 

which place it is named. In that locality it has a thickness of from 50 to 75 

feet. To the west, at Marshall, it is not over 35 feet thick, and evidently it 

does not extend much farther westward. The shale has a light-grayish or bluish 

color, and is very friable. In places it is sandy. It is not represented in the 

Yellville quadrangle, but is described here in order to give the full sequence of 

rocks in the section along the northern border of the Boston Mountains. 

Batesville sandstone.-The ·Moorefield shale is succeeded at Batesville by sandstones with some interbedded shale. In certain localities to the west the formation contains interstratified limestones, which, where they are weathered, appear 

sandy. Where the Moorefield shale is absent this formation rests directly on the 

Boone formation and is usually found in this position between ,Marshall and 

Fayetteville. The thickness of the formati9n in the Yellville quadrangle is about 

75 feet. The conspicuous portion of it is an even-bedded, yellowish-brown sandstone, which is seen exposed in the roads and as ledges along the creeks around 

St. Joe and just to the northeast of that place. It breaks into slabs, which are 

I 
.. 

CARBONIFEROUS ROOKS. 27 

convenient for building. The stone which is thrown out from wells dug into 

this formation shows its unweathered character to be iu places decidedly limy 

and its color light-gray. Sometimes it has an oolitic phase. The area of its 

exposure in this district is limited to the base of the slopes of the country 

immediately surrounding the isolated hills and mountains to the north of the 

Bo~ton escarpment. 

_Fayetteville shale.-The conspicuous portion of this formation is a bed of 

black, carbonaceous shale, which is usually thinly laminated. ~t frequently exhibits a jointed structure, and upon disintegration falls into small fragments. Its 

thickness varies from about 50 feet up to 200 feet. It is named from exposures 

around Fayetteville, where it is conspicuous in the valley of the West Fork of 

White River. This formation rests upon the Batesville ~andstone, or, where. that 

formation is absent, upon the Boone formation. 

The lower portion of the black shale in the Fayetteville formation contains · 

lenses of dark-blue, siliceous limestones at . some places. The limestones are an 

inconspicuous element, somewhat concretionary in character, and yield but few 

fossils. At Marshall there are beds of dark limestone in the upper portion which 

carry an abundant fauna. Considered in its wider occurrence it js rather variable, but the fauna serves to show its essential unity. 

Wedington sandstone.-Southeast of Fayetteville and westward to the State 

line, the Fayetteville shale is succeeded by a sandstone formation varying in 

importance, but usually having a thickness of between 50 and 150 feet. It is 

thin bedded and heavy . bedded, and carries some interstratified shale. It is not 

mapped in the Yellville quadrangle, although it is perhaps represented in a small 

area. It is described here in order to give the full sequence of the formations in 

the lead and zinc district. 

Pitkin limestone.-Succeeding the Fayetteville formation in the lead and zinc 

r egion, there is nearly everywhere a bed of limestone. It is not always · conspic-

' uous, since it frequently occurs on ·slopes and is covered with debris of sandstone 

and shales from the higher formation. Its thickness where well developed is 

usually from 10 to 40 feet. In exceptional cases it is thicker. It sometimes has 

associated with it sandstone beds which contain the same fossils found in the 

limestone. The Pitkin limestone has been called the "A.rchimedes limestone" by 

the Arkansas survey, because of the presence of this easily recognized bryozoan, 

the screw-like stems of which are seen in the weathered surface of the rock. In 

the northwestern part of the State, around Fayetteyille, the limestone thins out 

to a pebbly stratum, and disappears from the section. Along the north front of 

the Boston Mountains, ho~ever, it is a very persistent ledge, and the beds are 
28 ZINC AND LEAD DEPOSITS OF NORTHERN .ARKANSAS. 

frequently massive, and give rise to an escarpment, a bench being ·developed on 

its. upper surface. This formation is regarded as the highest one of the Mississippian series. It is probable that · the thinnjng to the no:rth and west is. due to 

shore conditions, and its absence in some cases may be due to erosion previous 

to the deposition of the Pennsylvanian series which succeeds it. It is named 

from the post-office of Pitkin, in Washington County, south of Fayetteville. The 

exposures in that vicinity have b~en well described and noted in reports by the 

Arkansas survey. ln the Yellville quadrangle it is found near the upper part 

o£. the two mountains, 1 t and 2 miles northeast of St. Joe. The formation there 

is about 90 feet thick. 

PENNSYLVANIAN SERIES. 

Morrow formaaon.-Under this name is described a variable formation, con-

~isting of shales, in which are some thin limestones and occasional sandstone beds. 

The basal portion is usually a sandstone or a Randy shale. Above this there is the 

limestone which has been called the Pentremital limestone by the Arkansas survey. 

Inasmuch as this is not a geographic term, the name "Brentwood" is applied to 

it in this report.. The limestone sometimes occurs in .a single ledge, but is often 

separated into two ledges, between which shales and sandstones intervene. The 

stratification is variable, and because of the absence of the limestone at some 

localities it may be considered as a lens within the Morrow formation. The third 

member of the formation has usually been designated the coal-bearing shale. In 

the vicinity of _Fayetteville, where it has been more particularly studied, a bed 

of coal is found in this shale at a number of places along the northern border of 

the Boston Mountains. It is seldom thick enough to be mined profitably, but 

has been opened and is used locally, particularly in vV ashington County, whelfe 

it is about 14 inches in thickness. Within the area discussed in this report coal 

is said to have been found in Gaither Mountain, but it is not of any importance. 

Some evidence of prospecting for it was seen on the slopes of Boat Mountain, but 

no information in regard to its character at that place was obtainable. 

Not infrequently there is a stratum of limestone above the coal-bearing shale 

which forms a variable lens, and in the vicinity of Fayetteville it has been described 

as the Kessler limestone. It is seldom more than 5 feet thick, although it reaches a 

thickness of 20 feet, and its presence in the slope is usually shown by thin slabs 

a short distance below its point of outcrop. Above it there are a few feet of 

shales and thin sandstones which belong in the Morrow formation. The upper 

limit of them is rather indefinite, but at many places is marked by the presence 

of heavy sandstones which carry quartz pebbles. 
RELATION ·OF FORMATIONS TO ORE DEPOSITS. 29 

Winslow formation.-This name, which is taken from the town of Winslow, 

south of Fayetteville, .ii) the Boston Mountains, is here applied to rocks which 

have usually been designated by the term Millstone grit. The base· of the . formation is at most localities characterized by the presence of quartz pebbles. The 

formation attains a great thickness in the Boston Mountains, and its upper limit 

has not yet been definitely placed. .As compared with the .Morrow formation 

below it, it contains much more sandstone, and the beds are oftep. massive and 

exposed in heavy ledges, which give rise to escarpments. No persistent limestone beds have thus far been found in the Winslow, and the sandstones . have 

not yielded fossils, although no doubt they contain them at some places. Ther~ 

are shale beds in the upper part of the formation, but in the southern border of 

the lead and zinc field only the basal portion is represented, and within the 

Yellville quadrangle it, is found only on the top of the two small points about 2 

miles northeast of St. Joe. 

GROUPING OF THE ROCKS WITH RESPECT TO ORE DEPOSITS. 

Ne1)rly all the ore deposits occur in either the Boone or Yellville .formations. 

They are more important and more widely distributed in the Yellville formation, 

which occurs principally in the northeastern part of the district, and is the lower 

of the two. The Boone formation is ore bearing at a few places in the ~orthern 

'part of the field, but most of the mining d~velopments in it are in the southwestern portion. Between these two ore-bearing formations there intervene some 

thin ones (the Izard, Polk Bayou, Key, Sylamore, and the St. Joe member), which 

are represented on the detailed geologic maps of the northern and southern parts 

of the Yellville quadrangle (Pis. II and III). They seldom ~rry any ore, and are 

grouped with the other rocks on the general map of the district (Pl. I), since 

they outcrop in narrow bands, which can not be shown on a small scale. The 

Key sandstone is an easily recognized formation, and is p.s~ful in the field for 

determining the division line between the upper and lower ore-hearing rocks. 

Many of the mines in the Yell ville formation are at ' horizons a short distance 

below the Key sandstone. The undifferentiated Carboniferous shales and sandstones shown on Pl. I are bov~ the Boone formation. They are not ore 

bearing, and limit the field to the south and west. They include the Batesville, 

Fayetteville, Pitkin, Morrow, and Winslow formations. 

HISTORY OF PHYSICAL CHANGES. 

Sedimentation.-In northern .Arkansas, as will be gathered from the foregoing 

discussion, the formations are all of sedimentary origin. The nearest igneous 

rocks are in the St. Francis Mountains, in southern :Missouri~ ip. Camden County. 
30 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

Mo., where there is a small pegmatite area; near Spavinaw, Ind. T., where a 

granitic dike occurs, and southwest of Little Rock. The few deep wells which 

have been drilled do not reach the igneous basement upon which the sedimentary 

rocks were deposited. There is no evidence of intrusion in the district~ and 

igneous agencies must be left out of consideration in seeking an origin for the 

ores. 

Practically all large limestone bodies have associated with them more or 

less zinc and lead ores. The ores may not appear except in occasional separated 

crystals or small pockets. This is the condition where the concentration of their 

original contents has not taken place. In northern A1~kansas there are two limestone formations which are capable of having furnished the zinc a~d lead. These 

are the Yell ville and Boone. 

During Ordovician time the conditions of sedimentation in northern Arkans~s 

varied but slightly _until near the close. The rocks are principally dolomites, 

generally uniform in character. The occasional shale beds which are found do 

not have wide exten~ and apparently grade into limestones when followed laterally. 

Near the close of the Ordovician a bed of sandstone (the Key sandstone) was laid 

down. It has the appearance of a beach or shallow-water formation. Occasional 

lenses and beds ~f this character are found interspersed in the dolomites, and 

sandy material is found in varying proportions in the dolomites themselves. After 

the Key sandstone the conditions were slightly different, although the rocks which 

were formed are much like the lower dolomites in character. Ordovician time 

was one of wide submergence, and except for the occurrence of the Key sandstone 

the Ordovician system bas the appearance of being a continuous o~e. The Ordo-

_vician rocks are important as an original source of the ores. Large~quantity analyses of therri, made by the Missouri geolOgical survey, have shown that where no 

ore is apparent a minute amount of various metallic sulphides can be detected. 

Although it is a very small percentage, it is.-- wholly adequate, if concentrated, 

to supply the material of the ore bodies, since the mass of rock is enormous, as 

compared with the deposits which are found. 

The Silurian rocks, which follow the Ordovician, are not developed in the 

district here discussed. They may have been deposited over the area, and removed 

during the erosion period which immediately followed. In the vicinity of Batesville the Silurian limestones are well represented. 

In Devonian time sedimentation in Arkansas was confined to irregular areas 

which represent the arms or borders of an encroaching sea, land conditions having 

prevailed through most of thi$ period. The deposits are shales and sandstones, 

which have a maximum thickness of but 40 feet, and in the area here discussed 
, SEDIMENTATION .AND EROSION. 31 

seldom more than 10 feet. The shales carry phosphatic pebbles, and are believed 

to be of estuarian origin. 

The Mississippian series in this district has at its base the Boone formation, 

which carries a large amount of chert~ During the time of its deposition the 

same marine conditions which prevailed in northern Arkansas extended far into 

~ndian Territory, Kansas, and Missouri. This may be regarded as a second 

period of calcareous sedimentation, and one equally important with the Yell ville 

formation as regards the origin of the ores. These rocks, like the Ordovician 

dolomites, according to large-quantity analyses, may have furnished metallic 

sulphides through concentration by circulating waters . . 

After the deposition of the Mississippian limestone shallow-water conditions 

may be said to have prevailed. The rocks are sandstones and shales of variable 

character, with the exception of the Pitkin limestone, which is a relatively thin 

formation and one yv hich is not important with respect to the ores. 

The transition from ::Mississippian . to Pennsylvanian time was probably marked 

by an unconformity, and in the beginning of it conditions were favorable for the 

accumulation of thin beds of coal. These deposits suggest a gradual submergence 

and low.:lying land areas. 

Erosion.-As has already been shown, there were interv~ls during which 

erosion occurred. The only one of much importance was in the Devonian 

period. The sediments which were. deposited during it are relatively insignificant, while the beveling and removal of the rocks during this time were 

very extensive, as is indicated by the fact that the succeeding Carboniferous , 

formations rest successively upon the Sylamore, Polk Bayou, Izard, and Key 

formations, and even the last has at many places been thinned to a considerable degree. There is no means of knowing what thickness of · rocks aboye 

the Polk Bayou may have been removed, and beyond the limits of . the district 

it is not improbable that erosion reached down to the Yell ville formation. The 

effects of the wearing down and weathering of the land surface on the ore 

contents of the rocks are so far obscured that they ' can not be taken into consideration. There are no ore bodies now known which can be said to have 

origina~ed at this time, and as changes of the same character took place at a 

iater period the effects of the earlier changes can not be determined. 

The present epoch of erosion reaches back probably to the beginning of 

· Tertiary time. During this epoch a much greater mass of the sedimentary rocks 

bas been removed than in the Devonian interval, and the effects are more readily 

seen. This erosion has given rise to the present topography, but -certain earlier 
32 

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' ' 

ZINC AND LEAD .DEPOSITS OF NORTHERN ARKANSAS. 

forms of the land surface have riot been wholly obliterated 

(fig. 1). The rocks which have been removed were the northern extension of the undifferentiated Carboniferous shales and 

sandstones, the JVIississippian limestones where they are not now 

represented, and · a considerab~e mass of the lower rocks in the 

area in which the Ordovician chiefly occurs. The history of 

the region indicates that in Tertiary time a plain was developed which coincided largely with the upper surface of the 

Boone . formation or the Mississippian limestone. At that time 

the lower rocks were not so widely uncovered, and the shales 

and sandstones formed mountains and isolated areas to the north 

of the preseilt escarpment of the Boston Mountains. This 

stage was a transitory one, and the downcutting of the streams 

and the further wearing away of the land surface have brought 

~bout the present features of relief, and exposed the rocks as 

they are found at the surface to-day. 

The local changes in the rocks which remain mai be attributed to the circulation of ground water. The modificatkins of 

the circulation of th~ ground water which have taken place 

from time to time and the conditions which influence the circulation will be described later in this report. 

DifcYrrnation.-No extensive disturbances occurred in the 

district to change the rocks from their original nearly horizontal position. The area has suffered numerous oscillations, 

but it has always been remote from the principal effect of the 

forces. The · unconformities mark the ch~nges in the attitude 

of the rocks with respect to sea level from time to time, but 

during la~er periods, especially after the close . of sedimentation, the record of physical changes can be inferred only from 

the surface features. 

Within the rocks themselves two principal classes of structure are seen. These may be attributed to movements in the 

vertical plane . which have produced fractures and faults, and 

to movements in the horizontal plane which have given rise' to 

breccias. Locally, there are exhibited minor flexings of the 

structure, as 1s shown. by occasional well-marked dips; but no 

d~finite system of folds can be made out. The structure may 

be spoken of as undulating, giving rise to local domes and 

.. 
DEFORMATION. 33 

' 

basins or shallow synclines and low anticlines, the axes of whi,ch are not clearly 

discernible. · The rocks apparently have suffered considerable deformation as . a 

result of compressive forces. This has given rise to occasional fracture zones; 

but a second, and perhaps more important, result was brecciation of the beds. 

Thi8 was produced by the differential movement of the strata, and is particularly 

exhibited . in the rocks of the Yell ville formation (Pl. VIII, .]J). The variation 

i~ the structure of these dolomites, which are in places massively bedded, and in 

other .places thin bedded, laminated, and even shaly, resulted from the lateral 

movement . being taken up in varying degree by · the individual beds, so that the 

motion due to compression was such as is produced by forces acting . in couples 

(fig. 2). The brecciation is due to the tendency of the pieces resulting from the 

HEAVILY BEDDED 

FIG. 2.-Diagram to show how stress may produce, differential movement and brecciation as a result of variation in 

· the character of the rocks acted upon. 

breaking of certain brittle strata to shear past each other, ·or to. rotate with the 

horizontal movements of the adjacent beds, so that the fragments l;tre relatively 

displaced. 

In the Boone formation compression produced principally fracturing and 

fissuring. The ~ails of the fissures not infrequently exhibit slickensiding, which 

has been produced by the rocks moving past each other horizontally. 

The faults of the district are, with few exceptions, normal faults. All the 

more important ones thus far ·stp.died belong in this class. It is probahle that 

some thrusting occurred at the time of compress~on, but no extensive thrust 

faults have 'thus far been found, though local ones are .seen in certain exposures 

and in the workings of some of · the mines. The normal faulting is believed to 

be of later date than the brecciation of the horizontal beds. In certain places 

the faulting has given rise to fault breccias, whicl:i are very similar in character 

to the bedded breccias, but are developed in a vertical rather than a horizo~tal 

plane. 

Origin of the structure.-Tbe fracturing and brecciation above mentioned are • 

probably due to stresses ·induced at the time of ; the folding in the Ouachita 

4538--~o. 24--04----3 

I • 
I 

·34 ZINO AND LEAD DEPOSITS OF NORTHERN ARK4.NSAS. 

1'1ountain and Arkansas Valley regions (fig: 3). At the close of the Carboniferous 

z period the thick mass of sediments which had accumulated in what is now 

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central Arkansas and western Indian Territory was folded in a . manner 

which suggests that it was thrust to the north. There are close folding 

and thrust faulting in the Ouachita Mountains and open folds in the 

Arkansas Valley region. In the southern border of the Ozark region, 

and particularly in the area under discussion, the generally hortizontal 

position of the rocks was retained, but there was considerable movement 

of individual beds. This movement was one of accommodation, and 

resulted in fracturing, without marked displacement. It took place 

largely along the bedding planes, and resulted in brecciation of the beds. 

The norm!ll faulting in this area is of later date, and is probably due 

to the readjustment following the crushing, or to subsequent oscillations 

of level. 

Geologic conditions influencing circulation of ground water.-The 

rocks which constitute the Ordovician system and the Mississippian limestones of the northern Arkansas district may be .considered as relatively 

permeable. In the Ordovician are local beds of shale, through which 

water would not readily pass, and the Devonian rocks, which have a very 

limited extent in the sohthern part of the field, are of about the same 

character and importance . in controlling the path of the ground water. 

They do not ha~e a wide influence, since they do not form persistent 

horizons. \\'here they occur they probably diverted the solution laterally, 

but no localization of ore deposits seems to be directly due to them . 

The shales lying above-the Mississippian limestone, on the contrary, 

have sufficient thickness to make them an important factor in determining 

the movement of ground water. Formerly they extended from their 

present boundary near the base of the Boston Mountains northward into 

:Missouri, and covered a considerable part of the Ozark region. Before 

they were removed they acted as a confining or limiting horizon. vV ater 

entering the Ordovician dolomites and Mississippian limestones where they 

outcrop, and moving with the dip as it passed southward, was under a 

hydrostatic pressure beneath these shales. There may have been a first 

concentra.tion of the ores, due to this circulation, an:d, if so, it could have . 

taken place from the upper portion of- the ~!ississippian limestones, 

which were below these shales, to the bottom of the Ordovician. This 

·reasoning may be appealed to in accounting for the ore . bodies . now 

found in the Mississippian limestones near the base of the Boston 

(/) Mountains, where these rocks have recently been uncovered by erosion. 

It is possible, however, that the concentration was caused by lateral circulation 
U. S. GEOLOGICAL SURVEY PROFESS IONA L PAPER NO. 24 PL. VIII 

A. MASS OF SIL I C IFI ED BRECCIA MARKING THE ST. JOE FAULT, NEAR 

THE EXCELSIOR MINE. 

B. NEAR VIEW O F DOLOMITE BRE CC IA CEMENTED WITH PINK SPAR. 

HiSTORY OF PHYSICAL CHANGES. 35 

adjacent to the' fractures in . which the ore bodies are found, and not by factors 

which are of such wide influence. · 

· .As erosion progressed· the shales and other formations iying above the 

Mississippian limestone were speedily removed from the more central portion of 

the Ozark region, so that the conditions which at first existed, as above outlined, 

were not long maintained. The main streams of the region, such as White 

River and its tributaries, so~n cut through these formations, so that water which 

may have formerly been under hydrostatic pressure found issuance in their 

valleys. .For a long period there have been no upper confining shales in the 

northern part of the field. The surface . water has been free to descend into the 

Mississippian limestones and Ordovician rocks, or through the Mississippian 

limestones into the Ordovician, and the point of issuance of such portions as have 

reappeared ·in the· surface flow has been in the valleys of the la1~ger streams. 

There no doubt has been lateral movement along bedding planes, through the 

more permeable strata and open and brecciated beds, and along the . surfaces ·of 

local shale beds. The saccharoidal Key sandstone, which is a conspicuous 

formation and one which is relatively porous, has probably been a horizon o:f 

lateral movement, assisting , in the tram;fer · of the ground water to places where 

it could find its way into the adjacent beds. 

Synclines.-The more important ore bodies are found along the course of 

the main channels followed by the ground water. Obviously, synclinal, structure 

would cause the convergence of solutions toward the axes of the synclinal 

' troughs. While mineralization ·is not confined to- such places, there are instances 

in the field where the ore is found in synclines. Professor Branner, in the 

report of the Arkansas geological survey, has emphasized the influence of folds 

in localizing the ore bodies and has advocated p~ospecting in such places for 

ores. .Although ground waters have been influenced by the dip of the rocks, . 

· there are so many openings through which they may pass, such as fissures, 

breccias, joints, and solution channels, that ' the occurrences of ore outside of 

synclines are not exceptional. 

Relations of belt of weathering and belt of cementation.-U nder the action of 

atmospheric agencies the rocks at and near the surface suffer loss of their mate 

rials and waste away . . This process may be described as weathering. ' Deeper in 

the earth the materials derived from the upper rocks are largely redeposited. 

This process is one of cementation. The belt of weathering and · the belt. of 

cementation are not separated by a sharp line, and, moreover, with .the processes 

of erosion the lower l!mit of the activity of the atmospheric agencies has cqnstantly 

migrated down ward. These belts are related to the topography of the country, 
36 ZINC AND LEAD DEPOSITS OJ!' NORTHERN ARKANSAS. 

the plane separating them . being higher in the hills than in the valleys. Consequently, during the long period which has been required for the removal of the 

C1J stratified rocks to their present limits there has been a shifting 

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downward and southward as. the streams have cut their valleys 

deeper and , the escarpments have retreated to the south. In the 

northern part of the field the belt of weathering, which was 

formerly in the :Mississippian limestones, has, since the removal 

of these beds, reached the Ordovician rocks. To the south, as a 

result of the rugged topography, it lies partly in the Ordovician 

and partly in the Mississippian. At the base of the Boston 

Mountains, where the shales and sandstones haye been but recently 

removed from above the Mississippian limestones, the belt of weath-

<li ering has descended but a short distance into the upper portion of C) 

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] PRINCIPAL FAULTS. 

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~ The faulting in the Arkansas :field was not studied m detail, 

~ except within the Yellville quadrangle. The principal lines of ~ 

r:J dispJacement are shown on Pis. I, IV, and V. The presence of 

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of displacement, are not _ in stratigraphic continuity; or in case 

the fracture has the same formation on either side and the section 

: is not exposed, by masses of fault breccias which sometimes stand 

~ above the adjacent rocks (Pl. VIII, A). Only the more importan~ 

structural lines are here described. A nu~ber of minor faults 

were noticed, and fault breccias were found which could not be 

attributed to definite lines of displacement, because of the absence 

of good surface exposures. 

The faults described below have all been noted by the Arkansas 

geological survey. The interpretation of them here presented 

dl.ffers, however, from that of the State rep~rt. Professor Branner 

in his descriptions and diagrams has discussed them as thrust 

faults. The observations made during the present survey led 

z to the belief that they are normal faults. This interpretation 

is consistent with the structural history of. the region as outlined above. 
' 

FAULTS. 37 

Rush~~Creek .fault.~This fault is named from Rush Creek, which follows the 

fault line in many parts of its course. The displacement varies along the line of 

the fracture, and probably is greatest in the vicinity of Rush post-office, where 

it was measured and found to be about 350 feet (fig. 4). The 

mountain · north of Rush is capped with the Boone formation, while 

these sam·e rocks are exposed in the bed of the creek . near the 

post-office. N otthwest of Rush the rocks on the north side of the 

fault all belong to the Yellville formation, while to the south, 

except in the creek valley, the country is ·oceupied by the Boone. 

'-':l 

Branch, just above the Climax mine, the line of the fault is indi- ~ 

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The fracture may be observed in a number of places, particularly 

:\t the bend of the creek, about one mile above Rush. On Spring· 

cated by a breccia. . The displacement is accompanied by drag- ~ <C 

ging of the beds on the south side of the fault, so that they g. 

turn .up like sled runners when viewed in a section from south to ~ 

north. There is evidence that the faulting is not confined to a 8 

CIQ 

single line of fract~re, since at the Morning Star mine there is ; 

displacement with a dowrithrow on the south side along a line ~ 

parallel to the main fault, and small displacements · have been ~ ::l 

vbserved in the workings of ·other mines, particula~·ly the vVhite ~ 

Eagle, which is in the fault zone. The Climax mine is. situated ; 

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near a fault which is pal-allel to the main one, and which, like it, ~- CIQ 

has a downthrow on the south side. The continuation of the ~ 

fault to the southeast beyond Buffalo Fork could not be made ~ ~ 

out. It is not improbable that the dispiacement is taken ~p by the § 

undulating stru9ture of the rocks. This is inferred from the dips ~ 

seen along the river between the mouth of Clabber Creek and the ~ 

Silver Hollow mine. 

Tornethawk fet ult.~The fracture which passes through sees. 7 

and 8, T. 16 N., R. 16 W., . in close proximity to the old Tomahawk 

copper mine, as it is called, brings the Carboniferous shales in 

contact with 'the Boone formation. · It is well marked at many 

places. . The throw reaches fully 350 feet. 

Parallel with and south of this fault are the Pilot Mountain fault 

and a few others, which are not very clear in the field. They have a z 

downthrow on the north side, and counteract the structure of the Tomahawk 

fault, so that the intervening area ha-s been dropped as a block. 

Pilot MountaJin fault.-The northern border of the shale and sandstone area 

northeast of St. Joe is defined by a fault which passes along the north side of 

Pilot Mountain (fig. 5). It is very easily observed in the field, because of the 
38 ZINC AND LEAD DEPOSITS OF' NORTHERN ARKANSAS. 

dissimilarity of the · rocks to the north, w hic.h belong to the Boone· f0rmation. 

Its direction is .approximately parallel to the Tomahawk fault~ and the two exhibit 

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structural relations s~mi1ar to those of the St. Joe fault. 

St. Joe fault.-The St .. Joe fault is north ·of and parallel to 

Mill Creek.. The downthrow is on the south side of the fault, 

and the displacement measures between 250 and 300 feet at different points. Throughout a portion of its course the Boone is 

brought in contact with the Yellville formation (fig. 6), but in the 

valley of a north branch of Mill Creek, the Key, Izard, Polk 

· Bayou, and the Sy lam ore are. exposed in contact with the Yell ville 

formation. 

.Mill Greek fault.-South of Mill Creek and nearly ·parallel 

with the St. Joe fault there is a line of fracture with a down throw · 

on the north side. The effect of this displacement, combined with 

the St. Joe .fault, is to depresS" a narrow ?lock, which, as a result 

of the drag accompanying the movement, has a synclinal structure. 

It is on this fault block that the portion of the valley of MilJ 

Creek having a west-east course has been developed. 

St. Joe monocline.-In the v:1lley of J\1.ill Creek, just north of 

St. Joe, th~ rocks are seen to be sharply . flexed . and to dip . to 

the south. Around St. Joe they resume their nearly horizontal 

position, but dip to the ·north, forming a shallow syncline (fig. 

6). The line of sharp .flexure extends northeastward and joins 

the Pilot :Mountain fault, as shown on the map, and it is not 

improbable that thei:e is displacement along it in its northern 

portion. The St .. Joe monocline, together with the Pilot Mountam fault, accounts for the presence of the Carboniferous shales 

and sand:;;tones found around St. Joe at a lower elevation than 

would naturally be expected.. To the south west of the line of 

the St. Joe the monocline extends ac:ross Buffalo. Fork toward 

the head . of Cave Creek. These localities have not been carefully studied, but the monocline is known to locally r>ass over 

into faulting. 

On the map published by the Arkansas geological survey a 

fault is sho~n extending in a northeast-southwest direetion through 

.z, T. 17 N., R. 17 W., into ·T. 17 N .. , R. 16 vV. The accompanying map (Pl. V) shows that there is a flexing of the beds along this line, but 

definite faulting was not seen, excepting in the southeast corner of T. 17 N., R. 17 

W. The structure lin~ is approximately parallel with the St. Joe monocline. 

, 
·. 

... 

:FAULTS AND ORES . AND MINERALS. 39 

A similar undulation in the rocks ~as observed o~ Water Creek and its 

tributaries in the southeast corner of T. 17' N., R. 16 W. 

IIurricane fault.-The Hurricane fault for a ·portion of its course follows 

Hurricane Branch~ and to the west crosses Davis Creek. It appears · to be a 

continuation_ of the St; Joe fault, or at least may be said to 'be a similar displacement which -has apparently the sarrie direction . . It is clearly marked in 1'. 

16 N., R. 18 W., where shales and sandstones are found oq the south side of it 

and .. the Boone formation on the n~rth. In the valley of. Hurricane Branch the 

displacement combined with erosion has exposed . the Yell ville forlll;ation on the 

north side in .contact with the Boone formation on the south . . Where it crosses 

Davis Creek it is marked by ~imiliar relations. The Big HuiTicane mine and 

the Spier mines are near . the fracture, and their workings are in the breccia 

which has been produced by the dragging. 

ORES AND MINERALS·. 

SULPHIDE ORES. 

Zinc sulplu:de, _. or sphalerite . ._ This ore, which is commonly called blende, or 

'~jack," is the most important one in northern Arkansas. It" is composed, theoretically, of 67 per cent of zinc ·and 33 per cent of sulphur; but as" a. result of 

the impurities the amount of metallic zinc varies somewhat. The ·analyses of 

specimens from northern ·Arkansas average close. to 66 per cent. , The . ore as 

marketed, however, does not always approach this purity, since in cleaning . it is 

impossible to completely separate all other miner.al matter from it. · The' price 

. per ton is based upon ore which contains 60 per cent, and if· assays indicate more 

or less the price is correspondingly higher or lower, usuaJly the variatioli being 

$1 for each per cent. 

Lead sttlphide, or galena.-This is the principal lead ore of northern Arkansas. 

It oc~urs in well-defined cubic crystals, or as crystal aggregates. Pure galena 

contains 86.6 per cent lead and 13.4 per cent sulphur. When smelted it yields 

about 80 per ce~t lead, since a portion is volatilized and lost. The nodhern • 

Arkansas ore contains practically no silver, which is sometimes found in galena. 

OXiDIZED ORES. 

Zinc siUcate, or calamine.-The amount of metallic zinc in this ore is theoretically 54.2 per cent.. Because of the fact . that it is depo~it~d secondarily and 

in intimate as~ociation with other . materials from which it. is difficult to separate 

it by jigging, the commercial product . as marketed usually carries but from 40 to . . . . 

·50 per cent of metallic zinc. It is translucent, has a ·vitreous luster. and varies 

from nearly colorless to yellowish arid brownish. It usually occurs in irregular 

masses, but on free surfaces forms bunches of thin, tabular crystals. It is 

... . 
40 ZINC AND LEAD DEPOSITS O:B' NORTHERN ARKANSAS. 

commonly associated with zinc sulphide, from which it has been derived as an 

alteration product. The workings in which it is found usually carry more or less 

clay and so-called tallow clay. , 

Zinc carbonate, or s1nithsonite.-This ore, which -is usually spoken of simply 

as carbonate, or sometimes as "dry bone," contains theoretically 52, per cent of 

metallic zinc; but specimens of this purity are rare, and the commercial product 

of necessity falls much below. The better grades of ore are somewhere between 

40 and 50 per cent. Smithsonite assum~s a v~riety of forms, the common one 

being the so-called gray carbonate, which resembles a limestone in texture. 

Another variety is of stalactitic form, which it assumes where the mass has been 

deposited in successive layers in cavities. When this form is broken it usually 

exhibits a banded structure, and when weathered the · carbonate is seen to occur 

. in sheet-like layers, slightly separated from each other, the intervening space 

being filled by other material, or in weathered specimens consisting of irregularly connected cavities from which some substances have been dissolved. Not 

infrequently . smithsonite exhibits a mammillary or botryoidal structure. This is 

found where it is deposi.ted upon free surfaces: The color of the ore varies 

according to the foreign substances which are present. Occasionally it has a 

yellowish coldr, in which case it is known as "'turkey . fat." This color is produced by cadmium sulphide, which is frequently combined with zinc .ores. Much 

of the smithsonite has an earthy form, and not infrequently it has the appearance 

of yellowish or brownish sand. This is due to its having been deposited irregularly and in small masses within the rocks and· to subsequent decay. 

Hydrozincite.-Hydrozincite is the hydrous form of smithso:nite, or zinc carbonate, i. e., zinc carbonate combined with more water of crystallization. It has 

a white or yellowish color and an earthy texture, somewhat reiembling chalk. 

It is commonly associated with smithsonite·. 

Lead carbonate, or cerussite.-T4is mineral occurs in limited amount, associated with the deposits of galena, and' is a superficial alteration product . from 

that ore. It can scarcely be said to be of commercial importance in northern 

Arkansas, although it is found in some shallo\v diggings. Usually it is seen as 

a coating over crystals of galena, or as a thin, white shell after the galena has · 

· been partly removed. 

Hydrocerussite. -This mineral bears the same , relation to lead carbonate that 

hydrozincite does to zinc cal·bonate, but is not common. 

Tallow clay.-This is not a definite mineral, and is at present not an ore of 

zinc, as no means have been devised fm smelti:qg it. It contains a variable amount 

of zinc silicate, and is allied to calamine. It occurs filling pockets and seams, 

and when :first exposed has an unctuous feel. The color is variable, an£1 it may 
.. ORES AND MINERALS. 41 

be mistaken for ordinary clay. Commonly, however, it may be distinguished by 

its behavior upon drying. When exposed to the air it cracks and shrinks in a 

peculiar way, as the result of the loss of water. 

ASSOCIATED MINERALS. 

Dolomite spar, or pink spar.-By far the most common mineral with which the 

zinc of northern Arkansas is associated is pink spar, which is a crystalline form 

of dolomite and consists of lime and magnesian carbonate. It has rhombohedral 

faces, and the crystal8 exhibit sharp curved edges, which are p~rticularly characteristic. 1 Its pink color is apparent in fresh specimens. On weathering it 

becomes discolored. Gray spar, which has practically the same composition, is 

another form which dolomite assumes on· crystallizing, but is more particularly t 

associated with the magnesian limestones than with ores deposited in cavities. · 

Calcite, or tiff-This mineral is simply a crystalline form of lime carbonate, 

and has the same composition as nonmagnesian limestones. It occurs sparingly 

in the district, 'although it is present in notable amounts in spme ·of the mines. 

Its scarcity is pro?ably due to the fact that lime in solutton in the dolomitic rocks 

is associated with magnesium and forms pink spar. Scalenohedral crystals are 

found in certain cave-like openings or water channels in some of the mines. I 

Secondary chert.-An important class of zinc ores are those which o'ccur 

embedded in chert, ~hich is clearly secondary to· the rock formations. Secondary 

chert has been formed by the redeposition of silica from solution. · It should not 

be confused with the primary chert or flint commonly occuring as lenses and 

:p.odules. Its color is usually l'llightly bluish, b.ut upon we~thering it is whiter . \ 

or is stained }rellowish by iron oxid~. Not infrequently masses are seen from .__ 

which the ores have been dissolved out, in which case the casts of the crystals 

give it a honeycombed appearance. 

"Quartz.-This mineral, which is the crystalline form that silica assumes, is 

found as small or minute crystals coating free surface~. The dolomites, which 

are more or less siliceous, sometimes have a cavernous structure, and these small 

openings are converted into quartz druses. Quartz is not important in the richer 

ore deposits, but it is characteristic of the leaner deposits in the .siliceous dolomites. 

Iron sulphide, or pyrite.-1'his mineral, which is sometimes called sulphur, or 

mundic, by the miners, has a golden-yellowish or brassy appearance; as a result 

of which it is often called "fool's gold." Most of the ore deposits of northern 

Arkansas are exceptionally free from this. objectionable mineral. It occurs, 

however, in small amounts at many localities, and in a few openings is as abundant 

as the zinc ore. At certain ·places masses are found occurring as pockets in the 

dolomitic limestones, but in such cases it has no commer~ial value. Associated.' 
42 ZINC .AND LEAD DEPOSITS OJ!' NORTHERN .ARK.ANS.AS. 

with the iron sulphide are sometimes small amounts of chalcopyrite, which 

contains a small percentage of copper, and this has given rise to the statement 

that copper ore is found in northern Arkansas. A notable example i~:~ the somewhat celebrated Tomahawk mine, at which place a large amoun,t of money has 

been expended in driving tunnels and sinking shafts. The ore found at this 

place consisted principally of pyrite, with a very small amount of chalcopyrite, 

and the occasional greenish and bluish stains have resulted from the oxidation of 

the chalcopyrite. 

Chalcopyrite:~ This mineral, which is not much different in appearance from 

pyrite, usually occurs as small crystals upon the surface . of other ores or upon 

the dolomite. It has a somewhat bronzy look when the ~urfaces are fresh. 

Upon oxidizing it gives rise to a bluish or greenish stain, as a result of the 

copper which it contains being altered to the carbonates, azurite, or malachite. 

These stains are sometimes seen in zinc carbonate. 

Gypsum.-The oxidation of sulphides, such as pyrite, sphalerite, and galena, 

gives rise to sulphate solutions. The metals are redeposited as carb.onates, and 

the sulphuric acid with which they were combined goes into solution. It may 

react on limestone and form calcium sulphate, or gypsum. This mineral is 

found at a number of places. It has a clear, crystalline form, can be scratched 

with the finger nail, and the thin plates intv which it splits ~an be slightly bent. 

These facts serve to distinguish it from calcite, which it somewhat resembles. 

Epsomite.-" Epsom salt" may be formed in much the same way that 

gypsum is, bu_t contain~ magnesium instead of calcium. It occurs as hair-like 

crystals in old workings. 

Goslarite.-This mineral is hydrous zinc sulphate. It occurs in old workings 

as light-colored crystals or as a crust. on the walls. . It is formed from zinc ore 

in solution and represents a transitory stage of the proce~s of ore deposition, 

since it may pass readily into solution. 

COUNTRY ROCK. 

The country ro~k in northern Arkansas, as will be g~thered from the discussion of the geology, is either a limestone-bearing chert or a magnesian limestone, 

or dolomite, ·which is more or less cherty or siliceous. From these rocks the 

pink spar and calcite have probably · been largely derived, as has also the secondary chert. The process of formation of these minerals is one of simple solution and redeposition, and took place along with the formation of the more 

important ores. These gangue minerals are of interest, inasmuch as they have a 

~earing upon the sour~ e and mode of desposition of the zinc and lead. 
ORJ£8 AND MINERALS. 43 

PREVAILING GANGUE MINERALS. 

According to . the prevalence of · gangue minerals the sulphide ore bodies may 

be placed in two classes, those occurring · with a siliceous matrix of secondary 

chert or with quartz crystals, and those found. with pink spar and calcite. . One 

or the other of these conditions is usually characteristic of a mine, although they 

not infrequently are found together. The oxidized ores are the carbonates and 

silicates, which are simple alteration products which have been derived from the~e 

two classes of deposits. . Usually they are not far from the sulphides, and frequently occur in intimate relation with them. 

GENESIS AND CLASSIFICATION OF THE ORE DEPOSITS. 

Sour e o.f the ores.-It is generally accepted that the zinc and lead deposits of 

this region have been formed by · the action of circulating waters, which have 

dissolved the ores w h · ch were first broadly disseminated in the limestones. 

Water has dissolved and carried them in solution to certain places where the · 

conditions were favorable for their reP.eposition. Stating· it differently, they 

have been derived from the belt . of weathering and the belt of cementation and 

largely deposited in the belt of cementation. A study of the nature of the ores 

and their gangue materials and of the geologic history of the region makes ·it 

apparent that at least the latest concentration of ;the ores in the Ordovician has 

been largely the result of downward and lateral movements. The metallic sul· 

phides may have been mainly derived from the Mississippian limestones, which 

form~rly had a· wider distribution, from the Ordovician, or from both formations. An examination of the Mississippian rocks shows that they have been 

leached by surface waters. Where they are exposed in railway cuts they exhibit 

decay to considerable depths; .and within the area of their outcrop are numerous 

sink holes in which the water disappears into underground channels.· The surface cherts which have been derived from the weatherings of those rocks are 

frequently porous and spo.ngy, thus indicating the loss of silica. In the Ordovician 

secondary silica is not infrequently a gangue of the ores. The Mississippian 

limestones contain notable deposits of zinc and lead at many localities in the 

Ozark region, and where there is ore in , the Ordovician the area was formerly 

overlain by the Mississippian limestones. The mines · of southwestern Missouri 

around Joplin are in this formation, and in northern Arkansas, as has already 

been stated, .prospecting has shown that in the portion of the district where they · 

have been but recently exposed to the action ·of surface waters, probably as a 

result of a first concentration, they carry considerable lead and zinc. 
44 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

Olass1'jication of the ore deposits.-The most important deposits of the district 

are the sulphide ores of lead and zinc, or, as they are commonly called, galena 

and blende. In the Ordovician dolomites there are two principal classes of these 

deposits, which are characterized by the gangue material. One class is distin-. 

guished by its occurrence with ·secondary cher~, which occurs as a siliceous 

replacement of the dolomites, or filling fractures in these rocks; in the other 

there is associated with the ore a large amount of dolomite spar, which forms a 

cementing material in the breccias. In certain of the m_ines there is, in addition 

to these main ore bodies, accessory ore which replaces the country rock to some 

extent adjacent to the main ore body without developing secondary chert or . spa~. 

In the Mississippian limestones the primary ore deposits are accompanied by 

secondary chert and calcite. They are related to fractures, and in some instances 

to fault planes. In the latter case they usually occupy breccias. Accessory ore 

replacing the country rock is sometimes· present with these deposits. 

The northern Arkansas field contains important deposits of oxidized ores. 

These are ~he carbonates and silicates. They ~re derived from the primary sul~ 

phides, and are due to the alteration of the S';Ilphides by the action of surface 

wate.rs. In discussing the genesis of the ores the important problem is the 

origin of the sulphide deposits,. the relation of the oxidized deposits to the sulphide deposits being clearly evideut . 

. Processes of primary deposition of tlLe sulphide m·es.-The action of ground 

waters in ·the belt of weathering, and to a considerable extent in the belt of 

cementation, resulted in the solution and transportation of the ores. , . As the 

water percolated downward and moved laterally, and perhaps later upward, it 

reached a place where deposition took pl~e. In the early part of the journey 

of the waters,. through the action of the carbon dioxide and the humic acids, 

silica was taken into solution, and the waters acco~dingly contained it in notable 

quantities., as weU as the ores in solution. In the latter part of the journey the 

action of these waters was the solution of lime and magnesium carbonate and 

the deposition of silica and sulphides, the resulting ores supposedly having been 

transported as sulphates. The reductjon of the metals to sulphides was probably 

accomplished througb the agency of ~rganic matter and pyrite in the rocks, 

directly or indirectly, and deposition of the sulphides occurred along with the 

formation of the secondary chert and spar. The superposition of the original 

Gherts in the Mississippian limestones and the occurrence of the secondary cherts 

and spar in the dolomites are entirely in accordance with this theory. 

Processes of dep01::ition of the oxidized ores.-The oxidized ores of northern 

Arkansas are the carbonates and silicates which have been derived from the 

sulphide ore bodies. They are, accordingly, relatively later, and have been pro-
GENESIS AND CLASSIFICATION OF ORE DEPOSITS. 45 

duced since erosion has brought the sulphides into the zone of weathering. The 

descending waters, · carrying carbon dioxide, have transformed the blende and 

g~lena. In some cases redeposition has taken place immediately, and not infrequently oxidized ores are found as incrustations on the sulphides. In other cases 

they are found along water channels, or in the open spaces and on the surfaces 

of the country rock. In the exposed faces of ore-bearing beds and the upper 

portions of workings secondary ores often predominate. When mining _ operations are carried into the rocks that are under cover or have been protected 

from the action of ground waters, the carbonates and silicates decrease, and 

g_alena and blende are found to be the predominating ores. 

S econdary deposition of the sulphides.- The sulphide ores which were dissolved by descending waters have not all been redeposited within the belt of 

-weathering. Such portions as were retained in solution upon reaching the belt 

of cementati~n were redeposited as sulphides, the processes in this case being 

the same as in ·the primary deposition and the ore bodies belonging to a second 

generation. In the ·lower horizons of the Ordovician dolomites considerable zinc 

ore is found, which occurs as bright, clean crystals associated with drusy quartz 

or in openings formed by fracture·. Such deposits are usually lean, and thus far 

no workable body of ore of this nature has been discovered. 

Observations have not shown that there is a criterion for clearly disting~ishing the secondary sulphide ores, which may have originated by migratioJ?. from 

the primary dep~sits, since it is not improbable that-the solutions at the time of 

· the first concentration may have deposited most of their ore in the upper horizons, 

in which case the deeper deposits would 'have the characteristics above described 

and assigned to the ores of the second generation. 

Sulphide depm;its associated 1.0ith secondary chert.-Wh~re chert is the principal 

gangue of the blende and galena, deposition in the Ordovician has taken place 

by the replacement of the dolomites and the tilling of fracture spaces . and 

cementation of breccias. Secondary chert when freshly exposed usually has a 

bluish color. It may be distinguished froin the other country rocks by means 

of its hardness, since it can not be scratched with a knife. It frequently has a 

banded or bedded appearance, which corresponds to the bedding of the original 

dolomite, and crystals of . ore usually well formed and distinct occur ·within the 

mass. In case some of the sulphides have been leached out, molds of the blende 

are seen, which · gives the chert a honeycombed appearance. The richer deposits 

appear to be rell:\ted to fracture zones, and occur along the fissures and replacing the adjacent beds. The path of the ore-bearing solutions in descepding has 

apparently been along fractures, and latterly along the bedding planes, and the . 

mineralization decreases away from the fracture zone. 
46· ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

Snlphide depo.sits in bedded breccias.-In the brecciated beds of the Ordovi-

. cian dolomites the open spaces between the fragments have afforded channels for 

the ore-bearing solutions, and the precipitation of the sulphides and dolomite, or 

pink spar, has usually taken place without dissolving the country rock to any 

appreciable extent. The pink spar is not always accompanied by ore. The sulphides have been deposited in a somewhat local way, many factors being concerned. Not infrequently in prospecting breccias containing pink spar and but 

little ore are fo~nd, and where the breccias are ore bearing they usually show a 

· \ decrease in the amount of ore when followed for a considerable distance. 

Sulphide deposits in.fissures.-In the -Mississippian limestones most of the mines 

and prospects are related to fissures, the ore occurring in material filling the 

fissures, or in the fissure and the openings adjacent to it. These deposits differ 

from those in the £raptured dolomites in being more clearly defined. , The gangue 

is usually secondary chert and calcite. The walls of the fissures exhibit slickensiding, as a result of the movement, and often indicate horizontal displacement. 

Sulphide deposits in fault bre.ccias.-Where the Mississippian limestones have 

been displaced by normal faulting and the rocks have been dragged they often 

15how brecciation. The angular fragments are largely primary chert, and the ore 

is associated with a calcareous and siliceous matrix which cements the breccia. 

Sulphide ore in the country rock.-In many of the mines and prospects the 

country rock has not been mineralized. In other cases, for a short distance 

adjacent to the fissures and fractures and water channels, the ore-bearing solutions 

have formed what is here called accessory ore. The action in this case has been 

one of replacement. The country rock exhibits recrystallization and_carries small 

crystals of ore. Where accessory ore is found the main ore body is usually 

rich, and there is a suggestion that deposition in the country rock resulted 

because of the large amount of ore in solution at ·these places. In the northern 

Arkansas district the scattered crystals of blende in the country rock are spoken 

of as disseminated ore. This term, unfortunately, is not quite appropriate, and, 

accordingly, the word accessory is suggested, since it does not imply the mode of 

deposition ,usually ascribed to disseminated ores. Accessory ore, being usually 

found associated with ·rich ore bodies, is looked upon by the prospectors as· a 

favorable indication. The ore in secondary chert is not included under this he~d. 

Ore associated with q·nartz druses.-Not infrequently in the Ordovician dolomites the lower ore horizons exhibit quartz druses and surfaces covered with 

minute quartz crystals. The ore occurs as clean, bright crystals deposited on the 

quartz. It seldom is found in large masses, but is distributed through the rocks. 

It . probably represents a , migration froni higher horizons, but it may have been 

deposited fro-m depleted solutions at the time of primary deposition. 
.. 

PLATE IX. 

~ .... -· 

47 

·, 
PLATE IX. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

FIG. A. Weathered specimen of dolomite; the more readily soluble bands have been removed 

in process of weathering. · In this particular case th~ laminre, which stand out in relief, carry 

more ,argillaceous and siliceous material, which' is not so readily dissolved 

FIG. B. Banded or laminated dolomite which has been recrystallized but carries no ore. The 

alternation of light and dark bands shows the lamination due to variation in the character of the 

material during the time of sedimentation. 

FIG. C. Fragment of dolomite which has been largely replaced by silica. This secondary silica 

carries zinc blende, which was deposited during the pr.ocess of replacement. The white bands, 

which are due .. to'" t~~ lamination ~f the ot>iginal dolomite, consist of argillaceous and siliceous 

material which has not been removed by t}le solutions that altered the rock. (From Big 

Buffalo mine, Marion County.) 

48 

' 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. I X 

A 

B 

0 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

PLATE ·x. 

4538--~o. 24--04----4 49 
PLATE X. ' 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

FIG. A. Illustrates the condition which a rock like the one shown on Pl. IX, C, assumes when 

it has been subj'ected to weathering. The blende has been largely removed or altered in place 

to zinc silicate. · (From Almy mine, Boone County.) 

FIG. B. Specimen consisting almost wholly of carbonate. The white lines indicate the argillaceous laminre of the dolomite which the carbonate has replaced. (From Morning Star mine, 

Marion County.) 

FIG. C. Fractured dolomite in which secondary silica carrying zinc blende has been deposited 

in the fracture. A small triangular piece of the dolomite is shown surrounded by secondary 

silica, and to the right of it there is a mass of sand grains which were carried into the fracture 

space at the time of the filling of it by the secondary silicate. (From lola mine, Marion County.) 

50 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. X 

A 

B 

0 

HAND SPEC IMEN S ILLUSTRATING GENESIS OF ORES. 
• 
/ 

PLATE XI. 

51 

( I 
PLATE XI. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES 

FIG. A. Mass of secondary silica which originally· carried zinc blende. The ore has been 

entirely removed, leaving molds of the crystals of sphalerite. 

FIG. B. Specimen illustrating the occurrence of galena in secondary chert. ( F.r:_om Ben Harrison mine, Marion County.) 

FIG. C. Specimen of secondary silica, in the surface of which large crystals of zinc blende 

were deposited. The ore, however, has been' removed. The cavities preserve distinctly the angles 

and planes which bounded the crystals. (From Markle mine, Marion County.) 

52 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XI 

c 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

PLATE XII. 

53 
PLATE XII. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

Frci. A. Section through a crystal Qf galena, the outer portion of which has been altered to . 

carbonate, forming a shell of this material enveloping the crystal. 

FIG. B. Weathered breccia which originally was much like C. The thin plates in it are due 

to the laminEe of the original rock, and the cavities are due to the removal of zinc blende, which 

was deposited during the process of silicification. (From Big Buffalo mine, Marion Comity.) 

FIG. C. Fragment, of breccia with a matrix of secondary silica. The angular pieces have 

resulted from the breaking of the laminated rock, which has been altered in the process of silicification. The secondary silica exhibits two phases, a dark and a light. Evidently there was some 

movement after the dark portion of the matrix was deposited, and the openings which were 

formed then were subsequently filled by the light matrix. Both the light and the dark secondary 

silica carry zinc blende in more or less definitely defined crystals. (From Markle mine, Marion 

County.) 

54 
U. S. GEOLOGICAL SURVfY PROFESSIONAL PAPER NO. 24 PL. XII 

B 

ILLUSTRATING GENESIS OF ORES 

PLATE XIII. 

. I 

55 

· ... 

\, 
PLATE XIII. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

FIG. A. MasE? of pink spar which was deposited in a breccia. Crystals of zinc blende exhibiting 

characteristic faces of this mineral are shown embedded in the spar. (From Red Cloud mine, 

Marion County.) 

FIG. B. Brecciated dolomite similar to the foregoing, in which the cementing material is nearly 

all zinc blende, and consequently is rich in ore. The lightest material is dolomite spar. (From 

Michigan mine, Baxter County.) 

FIG. C. Specimen from a weathered breccia in which the angular fragments arre dark dolomite. 

The lighter material is dolomite spar, or pink spar, which was deposited as cementing material. 

It carries some blende. (From Beulah mine, Marion County.) 

56 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XIII 

A 

B 

c 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

1 . 

PLATE XIV. 

57 
.. PLATE XIV. 

"< HAND SPiWIMENS ILLUSTltATING GENESIS OF ORES. 

FIG. A. Mass of pink spar which originally carried on its surface small tetrahedrons of chalcopyrite. Weathering agencies have altered the chalcopyrite to limonite, and the small amount 

of copper has given a green stain to the zinc carbonate whi~h has been deposited in round points 

and irregular masses on the dolomite. Unfortunately, this plate does not show the colors of the 

various minerals, and is consequently somewhat confusing. Those who are familiar with the ores · 

of the district will, however, recognize the characteristic appearance. (From Maumee mine, 

.Searcy County.) 

FIG. B. Fragment of rock which was once covered "\vith pink spar. Zinc carbonate was deposited 

on the surfac~ of the dolornite crystals so that they were completely covered. Solution has removed 

the pink spar, and the cavities where the . specimen has been broken reveal the space whieh the 

spar -originally occupied. (From Mcintosh mine·, Marion County.) 

FIG. C. Section through a mass of zinc carbonate which was deposited as a stalactitic growth. 

The spaces between the layers of carbon~te were probably once occupied by calcium carbonate 

which has been dissolved out during the weathering of the specimen. (From Carbonate Nose 

prospect, Newton County.) 

58 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XIV 

c 

HAND SPECIMENS I LLUSTRAT I NG GENESIS OF ORES. 

/ 

·RLAT XV. 

59 
PLATE XV. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

FIG. A. Section through an ore specimen the basal portion of which is zinc blende. The 

blende has been largely altered to zinc carbonate, which has been deposited on the free surface 

in botryoidal masses. The white portions consist of hydrous zinc carbonate, or hydrozincite. The 

centers of the concentrieally arranged carbonate are remnants of blende crystals. (From, Mcintosh 

mine, Marion County.) 

FIG. B. Specimen of zinc carbonate in which rounded masses are smaller and have grown 

from many points. (From lola mine, Marion County.) 

FIG. C. Charac~eristic appearance of botryoidal or mammillary zinc carbonate, which was 

deposited on a free surface. (From Morning Star mine, Marion County.) 

60 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XV 

B 

HAND SPEC I MENS ILLUSTRAT I NG GENESIS O F ORES. 

PLATE XVI. 

61 

•. 
PLATE XVI. 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 

FIG. A, Fragment of barren breccia from the Yellville formation which shows the effect of 

squeezing in shaly beds. (From Susquehanna mine, Marion County.) 

FIG. B. Fragment of brecciated Boone chert, wi~h a matrix of secondary silica. This specimen 

carried no ore. The angular pieces of chert have been much displaced. (From Rush Creek fault 

in Crystal Springs ravine.) 

FIG. C. Section of a second specimen of Boone breccia, in which the chert fragments have 

not been moved far from the original positions. This specimen carried some ore, which has l:>een 

dissolved, leaving casts in the matrix. (From Rush Creek fault in Crystal Springs ravine.) 

62 
LEAD AND ZINC DEPOSITS OE' NORTHERN ARKANSAS. 63 

DESCRIPTIONS OF MINES AND PROSPECTS. 

In the following descriptions not all of the mines and prospects ·of the 

district are mentioned. It is the purpose to set forth here such information 

concerning the district in general as will be valuable in forming conclustons in 

regard to the origin, character, and extent of the ore bodies. In the report on 

zinc and lead by the geolog-ical survey of Arkansas the descriptions of the ~ines 

and prospects are especially complete. The amount of development work done 

since that report was prepared is relatively small, except at certain mines, which 

are included in the followi:pg descriptions. 

No atte~pt is made to divide the district into stibdistricts or mining camps, 

since the ore deposits are not confined to definite areas. In taking up the 

descriptions, however, they . will be grouped by counties. . As has already been 

pointed out, the mines m~ght be referred to two classes, according to the formations in which they occur, viz, those in the Yellville dolomites and those in the 

Boone limestone and chert. This will be kept in mind in the descriptions. In 

some cases the precise location of the prosp cts and the correct name of the 

property could not be learned, because the land lines could not be found and no 

one was presen ~ to furnish information. 

I BOONE COUNTY. 

The devel6pment in Boone County is principally along Crooked Creek, beginning 2t miles elst of Harrison, and on Sugar Orchard Creek. In these valleys the 

Ordovician roclts are exposed. There are some prospects near the head of West 

Sug-arloaf Creef, and considerable work has been done in the valley of Bear 

Creek and its tributaries. At these localities the Yellville dolomite is the orebearing formatjon. The northern part of the county will probably be more 

thoroughly pro:5pected when the extension of the Missouri Pacific Railway is 

b~ilt through t.· Some of the showings of ore there are encouraging. The 

localities on Bet r Creek are not specially described in this report. The conditions 

in that part o] · the county are very similar to those where developments are 

more extensive., 

_l{orthern ta .-This mine is situated about 3t miles northeast of Harrison, 

on Crooked Creek. It is in the SE. t sec. 1, T. 18 N., R. 20 W. The opening 

occurs in the b~uff of the creek, about 80 feet above the level of the. water, and 

consists of a tJnnel driven just below the Key :-;andstone. The country rock is 

dolomite, occurring in heavy ledges, but exhibiting locally thin bedding or lamination. The rock has been fractured and jointed and shows slight undulations. 
f 64 ZINC .AND LEAD DEPOSITS OF NORTHERN .ARKANSAS. 

The ore occurs principally in a matrix of secondary chert, which is a siliceous 

replacement of the dolomite. Hand specimens show thin banding where the 

original structure is not obscure, and these bands correspond to laminre of the 

dolomite. When traced for a short distance, the unaltered condition of the rock 

may be seen where it is exposed in ~djacent openings. The ore-bearing stratum 

varies from 3 to 4 feet in thickness, and is rich in zinc blende. Some pink spar 

is found in this mine, and a minor amount of secondary ores, which have resulted 

from . the alteration of the zinc sulphide, occu~ as coatings on the blende where 

it is in large inasses, and also upon the gangue and associated minerals. At the 

end of the main tunnel is seen an open fissure, or joint plane, beyond which the 

country rock is apparently not mineralized. This opening has evidently been 

enlarged by solution, so that it resembles a narrow cave. Side tunnels from the 

main one pass through ore which varies somewhat in richness and promises to 

extend into the hill along the fractures which the beds exhibit. The amount of 

work done thus far has developed a considerable ore body. About 200 tons of 

crush rock wer~ on the dump at the time the mine was visited. This horizon 

is known to be ore bearing at adjacent localities, and has been prospected on the 

adjoining property, known as the Anna, where a shallow cut bas developed ore 

similar to that found at the North Star. Some prospecting has also been done lower 

in the bluff and in the creek bed, and a hole ·has been drilled on the bottom 

land on the opposite side · of the creek. More 'or less zinc ore has been 

reported in the lower horizons. As observed by the writer, the dolomites in this 

locality, which are lower in t..he section, exhibit quartz druses, and the ore is 

found associated with these cavities. Not enough work has been done in this 

mine to determine whether the ore in these lower horizons occurs in commercial 

quantities. 

Willis.-This opening is in the NE. t sec. 23, T. 20 N., R. 19 W., near the 

top of a small hill. It exposes a bed of fractured dolomite. . The horizon of 

the ore is but a short distance below the Key sandstone and St. Joe limestone 

member. It can be traced around the southern end of the hill, and has been 

prospected at several places. At the main opening the dolomite ·has been sheared 

somewhat, but does not form an open breccia, as iR frequently the case. The 

ore is found cementing the fragments of dolomite, and carries a small amount 

of pink spar as gangue. The strata above and below the ore bed are barren, 

and exhibit only jointing. 

Eliwir.-This prospect, situated in the SE. t sec. 25, T. 20 N., R. 19 W., 

consists of an open cut. The ore is principally galena. associated with chert in 

gray dolomite, and occurs in , pockets. Considerable ore has been taken from this 

place. Across the ravine to the south there is an open cut and a tunnel. The 
MINE~ AND PROSPECTS. 65 

country rock is a close-~extured blue dolomite, full of cavities lined with quartz 

crystals: These cavities carry some blende and carbonate. 

Almy.--This property (Pl. XVII, B) is in the NE.' t sec. 17, T. 19 N., R. 18 

W., _in a hollow tributary .to Mill Creek from the west. A number of openings 

have been Il1ade, all of which show more or less ore. The principal tunnel which 

was worked at th"e time the mine was visited was producing mainly silicate ore. , 

The workings were all relatively near the surface, and the rocks show the result of 

surface decay. The original ore is apparently zinc blende, deposited in a secondary 

siliceous matrix. The tunnels show that the rock was fractured · and displaced 

before the deposition of the ore.. Narrow fissures whieh are ore bearing were 

observed transverse to the bedding, and the ore was also seen in sheets parallel 

with the bedding planes. As a result of the action of surface waters, much of 

t~e original blende has been leac];led out and altered .to silicate, the secondary 

chert in such cases exhibiti-ng a honeycombed structure. In the faee of the _main 

tunnel both the original and secondary ores were seen, arid the rock exhibited s 

openings filled with tallow clay. Farther up the hill shallow shafts indicate that · 

the rock is of a similar character. _, The ore from this property, as it is mixed, is 

somewhat difficult to mill, but by judicious hand picking and sorting of the ore 

the milling: is successfully accomplished. At the time this mine wa_s visited · the . 

mill had been overhauled and work on the property resumed in a systematic 

manner. It was the only mine in the district which could be considered as 

having a steady output. Prospecting with the drill showed the · presence .of ore 

in lower horizons, and. a shaft is being sunk in order to determine the nature of 

the bodies. The indications are that, inasmuch as the old openings are under 

::;hallow cover, only mixed ores can be expected from them until they are 'driven 

a considerable distance in the hill. The results of the deeper workings wl.ll be 

of considerable int ~st in determining the amount of mineralization. at this 

locality. The -level of the .main tunnel is about 50 feet below the Key sandstone, 

but ore has been found af higher le.vels. _ 

Jackpot.-On the opposite side of Mill Creek from the Almy there is an 

extensive open cut or stripping in the ravine, which is known as the Jackpot 

property. The ore occurs in a bed of brecciated dolomite which is about 3 feet 

thick, and comdsts principally of blende deposited with pink spar. Some calcite 

is associated with it. The ore has b-een al'tered to a limited extent to carbonate 

and silicate. The amount of brecciation in the beds varies from place to place 

along the exposure, · and the ore is variable in richness. A large amount of 

crush rock is piled up, but thus far no ore has been marketed. This property 

is particularly interesting, because it is situated relatively a short distance from 

the Almy and exhibits conditions whieh have not been ·discovered in that prop, 

4538-~o. 24-04----5 
66 ZINC .AND LEAD DEPOSITS OF NORTHERN ..ARK..ANS..AS. 

erty. The same bed of dolomite is probably present on the west side o£ Mill 

Creek, although no opening has been made to _prove this fact. Apparently the 

processes which resulted in the formation of the ore in the Jackpot are altogether 

different frQm those which produced the Almy deposit. In the one the gangue 

mineral is largely dolomite spar, in th~ other S'econdary chert. The suggestion 

is strong that the ores of the Jackpot may have been derived from the deposits 

on the opposite side of the creek, af a time previous to the development of the 

present drainage, and when the rocks were eontinuous ·across the valley. I£ so, 

it is to be regarded as having migrated in solution, as already des?ribed in 

discussing the origin of the ore deposits. 

Frisco.-In the same section, on Mill Creek, about a hal£ mile south of the Almy 

and Jackpot, are located the prospects known as the Frisco property. They occur 

on both sides o£ the stream, and show more or less ore which is not unlike the Almy 

and Jackpot. 

Virginia J.-The Virginia J is in sec. 29, T. 19 N., R. 18 W. The development consists mainly of an open cut 40 feet long in the bed of a creek that crosses 

a small syncline. There is also a shaft several feet deep, from which it is claimed a 

good deal o£ ore was taken; but at the time the place was visited this was :filled with 

water. The ore is zinc blende, in considerable quantity, and occurs in dolomite, about 

75 feet below the St. Joe marble. It is confined to the syncline, where the dolomite 

is much brecciated. There is a small amount o£ ealcite, which with the ore forms the 

cementing material of the breccia. 

MARION COUNTY. 

The Ordovician rocks are extensively exposed in Marion County, in which are 

some of the best-known mines or the district. The ore-bearing horizons, which 

are in the upper portions of the Yellville formation, occur principally on the headwaters. of Sugarloaf, Music, Jimmie, · George, Sugar Orchard, and Tar kiln creeks, 

in the northern part o£ the county, and on Clabber Creek, Rush Creek, and in the 

valley o£ Buffalo Fork, in the southeastern part. Some prospecting has also been 

done in the southwest corner of the eounty. 

Iola.-The development work at this place consists of some shallow shafts an~ 

open cuts (Pl XVII, A). The property is in theSE. t sec. 25, T. 20 N., R. 18 W., 

in magnesian limestones immediately below the Key sandstone horizon. The sandstone is not conspicuously developed at this place, evidently having been eroded 

before the deposition of the St. Joe limestone member. :fhis formation can rea'dily 

be found. At the principal cut worked when this property was visited the rocks 

were fractured and displaced. The richest ore occurred in the breccia, associated 

with pink spar and considerable calcite. Besides blende, there is some galena. .A 
B. ALMY MINE. 
~ ; : ! ; ~ ~ : ... 

I 

' -, 
MINES AND PROSPECTS. 67 

fiss:ure a few inches wide was seen :filled with a sheet of this mineral. 

No. 7, blende occurs in. a ~iliceous matrix which fills the :fractures in t e dolomite 

and occurs along the bedding plane. Ore of the same character is fou d to some 

extent in the other openings. A tunnel driven into. the country ro 

carries practically no ore exhibits the jointing or fracturing, which ha 

principally along a north-south course. There is considerable evide ce of dis- · 

placement at the lola property, although no estimate of th~ amoun coulq be 

obtained. Altogether it probably does not exceed a fe': feet. The e deposits 

at this place, as at· a number of others indicated in the descriptions, 

ever, to be related to this structure. 

Tallow Olay.-This opening is in the SE. '!- sec. 35, T. 20 N., R. 18 W., not 

far distant from the lola. The development consists of a sha:ft a fe , feet deep, 

and- a tunnel driven several feet into the hillside, mainly along a clay- lled cavern 

in dolomite. A small amount of tallow clay and zinc carbonate were 

the wor.kings. 

Oolorado.-This mine is in the NW. t sec. 36, T. 20 N., R. 1 

from 

The · 

development consisted, at the time of visit, of . a shaft 'several feet deep, which then 

was not being worked and ?ontained S? much water as to prohibit 

The shaft was sunk in a zone or belt of · crushing similar to that i 

Markle is located. A few tons of good crush rock had been taken fro the shaft, 

the ore being blende, and. occurring in breccia. 

Ben Harrison.-This property is in the Sv\T. t sec. 25,. T. 20 N. 

The development is along a fault, which has a downthrow of about 15 The 

opening is in the St. Joe marble, .;which is jointed and shows consider 

The ore is chiefly galena. Only a small amount of blende is found. This mine 

is interesting because of its being situated in the St. Joe limestone me ber, 'V hich 

is not usually ore bearing, and the fact that it is so at this place is ndoubtedly 

due to crushing and displacement. The struc_ture at this. locality is apparently 

connected with a minor fault, which extends in a southeasterly direc ion, and is 

marked at several places by masses of br~cciated Boone chert, which stand up 

above the suri·ounding rocks in bowlder-like forms. Such a mass was seen on the 

Dodd City-Harrison road, near the center of the section. 

Markle.-This ~ine is situated in the SW. t sec. 21, T . . 29 N., R. 17 W., in 

what is known as Markle Hollow. At the time this mine was visited it was not 

being worked. The shaft is said to be 77 feet deep, · and to have been sunk 

through broken limestone. A tunnel , 50 feet long is driven into the side of the 

bluff, but was closed and idle. The ore was reported to be principally zinc 

blende, which occurs in a brecciated rock. Th~ gangue is principally secondary 

chert, and this carries· some galena. The principal amount of the ore came from 

"' . 
68 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

the tunnel. A new shaft had been .sunk to the ore-bearing horizon shortljT before 

the mine was visited, and the ore on the dump showed galena and blende in a 

brecciated siliceous rock which apparently wa:; originally a thin-bedded dolomite. 

There is considerable evidence of folding in this vicinity. The openings are just 

below the saccharoidal sandstone, which, together with the St. Joe, exhibits 

irregular dips in this locality. There is al~o evidence of minor faulting. A 

crusher and hand jig:; (Pl. XVIII, B) have been installed at this place, and considerable ore has been cleaned up and sold. 

Pilot Rock.-This opening is in the NW. t sec. 32, T. _20 N., R. 17 \V., 

in the valley of Sugarloaf, at the side of the Dodd City road. The principnJ 

working consists of a tunnel driven into horizontal dolomites. The country rock 

has been very largely replaced by secondary silica, and is brecciated, and exhibits 

small openings. The principal ore is blende. A large amount of carbonate is 

-present. There is also tallow clay in the opening, and considerable evidence 

of the decay of the rocks in the alteration of the ore deposit. The opening il:l 

about 50 feet below the horizon of the Key sandstone, which, however, is not 

conspicuous at this place. The St. Joe limestone member is characteristically 

developed, and furnishes a more ready guide to the geologic position of the I 

ore. It is interesting to note that the rocks are but "little displaced or dist~rbed, 

and that the . ore follows the bedding planes. The dip is low, and the relation 

of this mine to any definite structure is not at all clear. 

Nakomis.-This property is located in a ravine tributary to Sugarloaf Creek, 

in the southern half of sec. 32, T. 20 N., R. 17 W. The rocks are Ordovician 

dolomites. The principal working which was examined was an open cut in the . 

bed of the branch. At this pla-ce the ore is rather lean. A large amount of 

work had been done, and ·from tl{e rock which had . been ~toped a bin of crush 

rock had been sorted. A shaft was be'ing sunk at the mill, and lower down the 

branch prospecting with drill and the sinking of a shaft on a drill hole were in 

progress. Thus far no large ore bodies have been fou_nd, unless the reports of 

the drill records prove the existence of rich ore. . A large mill and boiler house 

have been built on this property (Pl. XIX, A), and work was carded on steadily 

during the season. 

Gm,ernor Eagl .-Th~ location of this property is in the NW. t sec. 7, T . . 

19 N., R. 17 vr., in a valley tributary to Little Sugar Orchard Creek from the 

west, in which the Ordovician dolomites are exposed. The workings, which 

consist of two shafts, were inaccessible, since nothing has be(m done at this place 

for some time. The ore is zinc hlende, which oecurs in a coarse breccia and 

associated with pink spar. The rock:; are reported to show, besides brecciation 

and fracturing, a slight displacement. The rocks which outcrop i11 this vicinity 

r 
. 

MINES AND PROSPECTS. 6 9 

exhibit no definite dips or important undulations. The surface waters have 

altered the ore deposit to some extent, as is shown by the presence of carbonate 

• and silicate ores and the weathered appearance of the dolomite crystals. 

Susquehanna.-This property is situated in the eastern half of sec . . 8, T. 19 

N., R. 17 \iV., on a smaU tributary of Little Sugar Orchard Creek. At this 

place a shaft bas been sunk and ,shaft bouse and ore bin built (Pl. XIX~ B). 

The ore is principally zinc blende associated with pink spar, and occurs in' a brecciated dolomite. Considerable prospecting has been done lower down on Sugar 

Orchard Creek, and has shown the presence of ore at horizons varying from 

just below the Key sandstone . down to the rocks exposed in the bed of the 

creek. The Le~on and Layton prospect is one of the most promising. 

Tarkiln.-This property is situated in the SE. t sec. 10, T. 19 N.~ R. 18 

W. The development work at this place includes a shaft, which was filled with 

water and therefore inaccessible when visited, and some operi c~ts. The ore is 

principally blende, with some carbonate and silicate. The crush rock found on 

the dump was rich. Not enough work has been done here to show the extent of 

the deposit. The ore borizbn is immediately below the Key sandstone. The rocks 

in this locality exhibit variation in dip, and show fracturing and jointing and 

some brecciation. 

Bear . Hill.-This property is located in the southern half of sec. 11, T. 19 

N., R. 17 W. The main shaft is in the upper part of the Ordovician dolomites, 

the month of it being about 40 feet below the St. Joe · member of the Boone 

formation, which is well expose~ near by, and at a somewhat less distance below 

the Key sandstone. A small mill and shaft house have been built (Pl. XX, A), 

and a crusher and band jigs installed, bu~ no work bas been done for several 

1 years, although the mine bas produced considerable ore. The main shaft is 

reported to be 157 feet deep, aild drifts have been made at various depths. The 

ore which was seen , at this mine was found 'in a breccia, and in material which 

apparently filled fractures. It consisted principally of blende. 

Batie.--This property is near the center of sec. 1, T. 19 N., R. 17 Vv., and 

consists of openings made in the be~ of Jimmie Creek. The ore found in _the 

Ordovician limestone is about 75 feet below the Key sandstone. The rocks have 

been quarried and blasted; exposing the ore deposit, which apparently follows 

the bedding. A shaft has also been sunk, but was filled with , water, so that it 

was inaccest:dble. The ore seen on the dump was apparently taken from this 

shaft. In these openings the principal ore is zinc blende, though some carbonate 

and silicate ores were found. The structure which appears to determine the position of the ore is brecciation. The matrix is to a large degree siliceous. and exhibits 
70 ZINC A::ijD LEAD DEPOSITS OF NORTHERN ARKANSAS. 

infiltration of sand grains and deposition of calcite and pink spar. By quarrying, 

a large quantity of ore can be obtained at this place without underground workings. 

Big Elephant.-These workings (Pl. XVIII, A) are in the NE. t sec. 30, T. 

20 N., R. 16 W. The ore deposits at this place are apparently related to a siliceous 

deposit which extends from the St. ,Joe "member of the Boone .formation down to 

the horizon of the Key sandstone. Dolomite spar is found in the lower beds. The 

principal ore is zinc blende, which occurs associated with the chert. It has, however, been largely altered by surface decay, and the rock which originally contained it has a cellular structure where the ore has been dissolved out. Considerable carbonate also occurs as a result of this alteration. In the upper part, in the St. 

Joe limestone member, there is considerable lead ore, which likewise shows alteration to carbonate. This mine has .interesting structural features, and the position 

-of the ore body is o:ne which is unusual in the district. The fact that the Key 

sandstone is thin at this locality perhaps accounts for the continuity of the ore 

deposit from the Carboniferous into the Ordovician. 

B ·ig Buffalo.-At the intersection of some deep ravines in the southeastern 

border of sec. 5, T. 19 N., R. 1 16 W., there are a number of openings which 

show a deposit of ore related to the bedding of the rocks. The horizon is in · 

the upper part of the Ordovician. The ore-bearing strata have been largely 

replaced by secondary chert, and exhibit thin bedding. In some places they 

have been brecciated, while in others their original structure is maintained~ The 

blende has been dissolved out near the surface, or adjacent to the water channels, 

leaving the· matrix with a honeycombed appearance. The effect · of this solution 

has also been to convert the blende into carbonate and silicate, which is found 

as a coating on the ore and rocks. This deposit, although, unfortunately, but a 

few inches thick, is singularly continuous and fairly rich. Another run is 

reported 12 feet above the typical one, and is said to be similar in character to . 

the lower. Prospecting was being carried on at the time the property . was visited, in the hope of finding a workable face of ore. 

Ol;ympia.-On Jimmie Creek near the mouth of Moccasin Creek a new townKingdon Springs-has been established. In this vicinity a number of ~rill holes . 

have been sunk and considerable prospecting done. Fourteen of th~ drill records 

were charted, for the purpose of showing t~e thickness of the ore deposits 

reported by the driller. The statement is made that the ore occurs in disseminated deposits of exceptional thickness. At the time this locality was visited no 

workable deposit had been opened. On a t.ract of land where four drill holes 

had been, sunk the OJ.ympia shaft was being put down in order to determine 

the nature of the bodies of ore which the driller reported. , Considerable difficulty was experienced in sinking this shaft, since a strong flow of water was 
U. S • • GEOLOGICAL SU RVEY PROFESSIONAL PAPER NO. 24 PL. XX 

A . BEAR HILL M IN E. 

B . BEULAH MINE. 

MINES AND PROSPECTS. 11 

encountered. When la13t visited it had reached a depth of about 100 feet, and, 

had passed through what was known as the upper run of ore. It was expected 

to reach a lower run in a short time. The rock upon the dump was dolomite, 

but slightly altered in any way, with the exception that it was more or less siliceous, and exhibited fracturing and cavities lined with quartz crystals. Some -of 

the beds are probably brecciated. But little pink spar was found. The mouth 

of this shaft is approximately 300 feet below the horizon of the Key sandstone, 

_ and is, accordingly, geologically much lower than most of the openings which have 

been made in the district. The results of this prospecting, when fully determined, 

will have an important b~aring upon the depth at which ore bodies may be found 

in the Ordovician. The nature of the rock, which is characterized by quartz 

druses, is not encouraging, although some beautiful specimens of ruby jack 

were found in pockets. - · 

North 8tar.-This opening is in the eastern part of sec. 9, T. 19 N., R. 16 W. 

It consists of an open · cut which has been extended along the hillside just below 

the Key sandsto~e. The rocks are the Ordovician dolomites, somewhat siliceous 

and showing infiltration 'of sand grains. The opening does not extend far into 

the hill. The rocks show the results of surface decay, and the ore deposits -have. 

been leached and altered to carbonates. The ore on the dump c_ontains a large 

amount of carbonate, alt9-ough the original deposit was plainly zinc blende, a 

considerable amount of which has been dissolved, as is shown by the cellular 

structure of the rocks which preserve the casts of the crystals. The rocks in 

this locality -show some undulation, although no definite dips could be made out. 

The beds are jointed and have been considerably fractured. An interesting feature 

of this deposit is the fact that some blende has been deposited on the saccharoidal 

sandstone where it has been jointed and slightly displaced. 

Summit IIo~ .-This prospect is located near the center of sec. 15, T. 18 N.,-

R. 15 "'\V., near the su~nmit of the divide. The rocks are nearly horizontal, bluish 

dolomites. The ore horizon is well toward the upper limit of the Yellville 

formation. The beds are . considerably fractured- and brecciated. The ore is 

mixed carbonate and silicate, with some blende. Five open cuts at about the 

same level constitute the workings. From 5 to 7 tons of ore-bearing rock have 

been thrown out of each cut, and a little more is still in sight in the walls of 

several of the openings. 

Dyson.-In the SE. i sec. 30, T. 18 -N. , ,R. '15 "\V., a considerable 1 exposure 

of a brecciated deposit h_as been made by quarrying and drifting. This property 

is situated well up on the hillside, and the ore-beating bed is near the top of 

the Ordovician dolomites. A large pile of crush rock was on the du,mp, and it 

was reported at the time the property was visited that a mill was to be erected. 
72 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

The ore body is clearly related to the bedding of the formations, and is found 

in a stratum which has been coarsely brecciated. The cementing material of the 

breccia is pink s par, which is rather abundant. From the' appearance of the 

faces of the openings the deposit has a tendency to run rather irregularly as 

regards richness, in s<;>me cases very little blende appearing ~ith the pink spar. 

Although this property is a promising one, in view of the fact that workings 

show lean ore in certain faces, it is probable that the percentage will vary considerably from place to place as the bed is worked into the hill and along its. 

face. This will necessitate judicious methods of cutting the gtotind. 

Bald J esse.-This opening is well up near the top o..f the mountain called Bald 

.Jesse, situated in the NW. t sec. 25, T. 18 N., R. 16 v\T. In ascending the 

eastern slope of this mountain thick beds of brecciated dolomite are conspicuously exposed where the surface is bare of soil and vegetation. The prospect 

which is here described is at a place where such a breccia is mineralized. The 

openings are about 50 feet below the horizon of the Key sandstone. Not very 

much work has been done, and, accordingly, the value of the ore body has not 

been determined. 

_Hawkeye.-On the east side of Clabber Creek, in sec. 4, T. 17 N., R. 15 W., 

_, a brecciated bed has been quarried in the hillside about 75 feet above the creek 

bed, and shown to carry a considerable amount of zinc blende associated with 

pink spar. This property is located on a vyry characteristic bed of breccia, 

which is continuous for a considerable distance, as is shown by the following 

prospects. 

Starlight.-This opening is to the south of the Hawkeye and apparently in 

the same geologie horizon. 

Eldorc(;do.-The breccia, which is continuous from the Hawkye to the Starlight, dips slightly to the south, so that at the Eldorado it is lower in the bluff 

of Clabber Creek. At this place it carries considerable zinc blende, but the 

. amount varies along the bed. . 

B eulah.---,At the Beulah·(Pl. XX, B) the original openings were made just above 

the level of Clabber Creek, and probably at about th~ same geologic horizon as the 

ore deposits in the Hawkeye, Starlight, and Eldorado. The ore in some places is 

a rich deposit of zinc blende assoeiated with pink spar in coarse breccia. It was 

found at several openings, and drill holes report it . at other places on the property. A large mill was erected for the purpose of concentrating the ores, and 

a working shaft was sunk and connected with the mill by overhead tramway. 

From the exposure of the ore near the creek bed a tunnel was driven to the 

working shaft, a distance of about 250 . feet, the most of whieh was through 

barren rock. This tunnel was driven on a level, and it may be that the ore 
U . S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XX I 

A.. C LIMAX lv1 1NE, 

B. M O RN I NG STAR M ILL. 

Co nnected with mine above by gravity tram. 

U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. XXII 

VIEW OF RUSH POST-OFFICE AND MORNING STAR MINE AND MILL. 

Courtesy of Mr. Bryan Snyder, general passenge r agent St. Loui s and San Franci sco Railway. 

• 

MINES AND PROSPECTS. 73 

deposit dips at this place, so that the tunnel passed out ·of the, ore. From an 

examination of the workings, however, it was apparent that the brecciation is 

frequently localized, and the ore deposits first encountered extend but a short 

distance before showing considerable variation, apparently as a result of the 

change in the structure "of the rocks. Some ore has been milled from , this mine, 

but the works are now idle. 

Zinc Basin.--The Zinc Basin ·o.spect, which is situated in the SW: -l- sec. 3, 

T. 17 N., R. 15 W., was new ly•· op~~d when visited. It is on a brec2iated bed 

very similar to that which is exposed at the Beulah. It is only a few feet above 

the level of the water in Clabbe~ Creek. The second opyning was being started 

near by. The ore at this place is zinc blende. An interesting feature at this 

prospect was the occurrence of a small amount .of mi:neral pitch, which seemed 

to be developed in the rocks which contained org·anic matter. The dolomite at 

this place exhibits thin :film8 of da~k, carbonaceous material along the planes of 

sedimentation. This has a bearing on the deposition of the ore, the fa!lliliar 

statement of the · precipitation of sulphide as a result of the presence of org·anic 

matter seemingly being verified in this instance. ' 

Climax.-This property (Pl. XXI, A) is in the NE. -l- sec. 1, T. 17 N., R. 16 

W., on a small tributary of Rush Creek. The openings are in the Ordovician limestones, a few feet below the Key sandstone, and consist of open cuts in the bed 

of the branch, and a working shaft at the mill. The ore found was principally 

blende, although some carbonate appears near the surface. The deposit is in 

a breccia, and fracturing is also plainly seen at this place. 'Just east of the 

workings a fault having a throw sufficient to bring thel Boone chert down to a 

level with the Key sandstone can be readily seen on the south side of the 

branch where the sandstone ledge is discontinuous. This fault is apparently a 

minor one, parallel to the main Rush Creek fault, elsewhere described. No work 

has been done which shows whether or not mineralization has occurred along 

it. At the time this property was visited the mi1l had been newly erected, but 

no ore had been milled, and sufficient work had not been done to determine the 

extent of the ore _body. 

JJforning Star.-This pr~perty is situated on the north side of Rush Creek, 

150 feet above the level of the stream, near Rush po~t-office, in the NW. -l- sec. 

10, T. 17 N., R. 15 W. · The workings consist of open cuts, all on about the same 

level. A gravity tramway has been laid in the. principal workings, and an- incline 

constructed to the mill, which is situated on the hillside below (Pl. XXII). This 

mine hat:; produced considerable ore, which is shipped by way of White River to 

Batesville, and thence by railroad. The mill (Pl. XXl, A) was built in 1898, but 

has . not been operated since 1900. The ore in thi~ mine, which has made it cele-
74 ZINC .AND LEAD DEPOSITS OF NORTHERN .ARKANSAS. 

brated, is a rich carbonate, which occurs in several forms. At present the principal ore shown in the workings is zinc blende, although a large amount of carbonate is associated with it. The workings are all· related to what appears to be 

a fissure or fracture parallel with the main Rush Creek fault. There are minor 

faults and fractures and brecciation observable. With the exception of some of 

the minor faults the amount of displacement can not be estimated. It probably 

does not amount to many feet, and is a subsidiary feature of the displacement 

which has taken place along the main fault. The country rock is a dolomite, 

and there is both secondary chert and pink spar associated with the ore. A view 

of the largest opening is shown in Pl. XXIII, A. The tract is seen entering 

opposite the fi~sure above mentioned. To the left i~ ·an irregular drift, in the 

walls of which rich ore is seen. To the east of the fissure, as here exposed, some 

shallow pits have been sunk which expose the material filling the fissure, and 

give reason to believe that it is continuous :for some distance along the hillside. 

This mine is not only interesting because of the rich deposit which it discloses, 

and the association of original and secondary ores, but because. of the structure 

which can be made out. Similar relations no doubt exist in other localities, but 

t}le fissures are seldom so . conspicuous, although they have evidently played thesame role in the processes of ore deposition, by determiii.ing the circulation of the 

mineral-bearing solutions. The deposition of the secondary ores appears plainly 

t? be the result of the leaching of the sulphides by surface waters and the 

redeposition of them as incrustations, principally as carbonate in stalactitic form,_ 

or as coatings upon the rock, and in some cases replacing the rock material. 

Kcintosh.-This mine is in the SE. i sec. 10, T. 17 N., R. 15 W., adjoining 

the Morning Star, and on the same hillside. The ore apparently occurs in the 

same horizon. It has been mined principally in an open cut and drifts from this 

cut. No fissure and no definite systerri of fractures could be made out at this 

~_ place. It is approximately in line with the fissure at the Morning Star, which 

if it continues as far as the Mcintosh, is disguised in the hillside by the debris 

of the slope (Pl. XXIV). I_n addition to the upper openings, some prospecting 

has been done on a level with the creek, and has resulted in the finding of a 

breccia carrying zinc blende in a matrix of pink spar. This ore all resembles, in 

a way, that in the breccia at the Beulah and Zinc Basin, which occur at approximately the same elevation on the north side of Rush Creek Mountain .. 

White Eag~e.-This mine (Pl. XXV, A) is in the NW. i sec. 11, T. 17 N., 

R. 15 W., in bottom land adjacent to Buffalo Fork just below the mouth of R.ush 

Creek. · The mine consists of a shaft 65 feet deep and a · drift run from the bottom of the shaft. The ore-bearing rock is a siliceous replacement . of the dolomites, and, although somewhat different from the deposit at the Morning Star 
L' 8. GEOLOGICAL SURVEY PROFESSIO NA L PAPER NO. 24 PL. XX III 

A. EAST END OF MAIN CUT AT MORNING STAR M INE, SHOWING FISSURE 

O PPOSITE EN 0 OF TRACK. 

B. Mel NTOSH MI LL. 

C o nn ected with mine above by cable tram. 

U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. H PL. XXIV 

MciNTOSH MINE, RUSH, ARK., SHOWING NATURAL EXPOSURE OF ROCKS SOMEWHAT OBSCURED BY WASTE FR O M THE OPEN CUT. 

Courtesy of Mr. Bryan Snyrler, general passenger agent St. Lou1s and San Fran cisc9 Railway. 
!" 

MINES .AND PROSPECTS. 75 

and Mflntosh, it is believed by some to occur at the same geologic horizon, but 

at a lo1wer elevation as a result of the dip. It was impossible to verify this by 

identifying the individual beds which outcrop at intermediate places; but it is 

not im~robable that' the mine is in the same general horizon, although the occurrence f f ore deposits at varying horizons makes it a doubtful aild unimportant 

point. 1 ...._L\.t the time this mine was visited no work was being done and none had 

b~en darried on for some time. It was, accordingly, filled with water and 

.inaccessible. From an examination of the ore upon the dump it was seen that 

there is associated with the deposit considerable quartz as coatings of small 

crystals on . free surfaces. ' Not much pink spar was observed. Calcite, however, occurs interestingly at this place .. A large mass of doubly terminated 

scalenohedral crystals was shown to the writer, which was reported to have 

come from a cave-like opening in the mine. Considerable conjecture a.od discus-

. sion has been. indulged in by those who have visited the .property, as well as 

those interested in it, as to whether . the Rush Creek fault passes through this 

ground and as to whether the ore deposit is related to fissures. In the absence 

of an examination of the workings nothing could be determined definitely · on 

this point. 

Maryhattiana.-On this property considerable prospecting bas been done in 

the bed of the creek and on the hillsides. The ore occurs in brecciated dolomite, 

and the rocks show some faulting and slight folds or ~aves. The vicinity is 

promising and of considerable interest, because it is situated south of the Rush 

Creek fault. The occurrence of ore along this creek shows th~t the ore bodies 

are not confined to the vicinity of the main faults. 

R ed Oloud.-Tbis opening (Pl. XXV, B), which consists of a large open cut 

on the hillside on the east side of Buffalo Fork opposite the mouth of Rush Creek, 

is in the NW. t sec. 14, T. 17 N., R. 15 W. It is about 70 feet above the level of 

the river, and extends for approximately 100 feet along the bluff. It is. a shallow 

stripping and exposes rich deposits, the ore consisting principally of zinc blende, 

which is fo.und associated with secondary chert and pink spar. In places where 

the deposit is especially rich it replaces the adjacent country rock. The structure 

at this mine is obscure. The relation of the deposit to others in this locality was 

not satisfactorily made out. The Rush Creek fault, which is in most places easily 

traced, should s~rike ac'ross Buffalo Fork somewhere near the mouth of Rush 

Creek. The throw of the fault near Rush post:-o:ffice is about 350 feet. It 

undoubtedly is less at many places, and apparent!; th~ displacement is taken up 

by irregular structure and diminishes before reaching Buffalo Fork, since it was 

not possible to locate the fault on the east side of that stream. The rocks in 
I 

7 6 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

the Red Cloud mine show some dip to the north, but it is slight and is not 

.apparently associated with any faulting. 

Silver I:lollow.-Thismine is in the N\V. tsec.13, T.17N., R.15 W., in the 

face of the south bluff of Buffalo Fork of \Vhite River. The lower opening, which 

is aboJit 20 feet above the level of the river at its ordinary stage, is in a brecciated 

bed which carries a rich deposit of zinc blende, especially near the beginning of 

the tunnel. Near the surface the ore has been altered to zinc carbonate. The 

original deposit is clearly related to the bedding of the rock mass, zinc blende 

occurring in a secondary chert and with pink spar. The tunnel has been driven 

for a considerable distance, and has passed into barren ground. The faces of 

the earlier workings still show good ore. The d~velopment thus far indicates the 

localization of the ore bodies in a manner which is not uncommon through the 

district, the position seemingly having been determined by fracturing of the country rock. The upper opening, which is about 50 feet higher in the bluff and 

about as far to the southeast, is an open cut in which work was in progress at 

the time the mine was visited. The ore body there has the appearance of occurring in a fissure. This is suggested by the difference in the character · of the rock 

on the two sides of the opening and by the shape of the ore body. It was 

imp~ssible, however, to ascertain whether this is the case, since in the newer working the limits of the ore body have not been reached and there are no satisfactory 

exposures on the bluff. The ore in the upper opening consists of zinc blende 

and zinc carbonate, associated with which is a large amount of pyrite. This is 

the only deposit seen in northern Arkansas where pyrite is abundant or associated 

with zinc in quantities which impair the commercial value of the mine. The oxidation of the pyrite and zinc blende has given rise to limonite and zinc carbonate. 

On the botryoidal surfaces the zinc carbonate is beautifully stained by the iron. 

Ore which carries such a large percentage of pyrite can not be cleaned satisfactorily by- the ordinary process of jigging, since the specific gravity of the two 

minerals is so nearly the same. In order to prepare this ore it will be necessary to 

·resort to a process of roasting and rejigging, or magnetic separation. By roasting the ore the pyrite is deprived of a certain amount of its sulphur and is 

rendered relatively lighter. 

The lower opening in Silver Hollow is free from pyrite. Thus ·far the 

workings do not show the relation of the two ore bodies. If the upper one 

occurs along a fault zone it is probable that the lower one is related to this 

structure. Future developments may demonstrate this, or show that the two 

masses have been independently segregated. 

Boat Creek.-This mine is near the mouth of Boat Creek, in the center of 

sec. 7, T. 17 N., R. 14 W. The ore deposit consists of' zinc blende, occurring 
U. S. GEOLOGICAL SURVEY PROFESS IONAL PAPER NO. 24 PL. XXV 

.A. WHITE EAG LE MINE. 

B. RED CLOUD MINE. 

, 

MINES .AND PROSPECTS. 77 

in rich masses associated with ·pink spar and replacing dolon1ite. Here, as in 

other places in the district, in. the process of ore deposition there has been 

produced what is sometimes referred to as disseminated blende. This term is 

used by the pro .,pectors in northern Arkansas to designate ore which is found 

in sm~U crystals and masses in the country· rock. The process of formation is 

not an unusual one, and may he more appropriately described under the name 

of i'eplacement. The ore-bearing solutions which gave rise to the ore occurring 

in the open spaces associated with pink spar in a breccia also dissolved the 

adjacent country rock and precipitated crystals of blende in the place of the_ 

material extracted. This apparently has occurred where the solution was rich 

in zinc, as is attested by the fact that the ore in the breccias . occurs in large 

masses. The Boat Creek deposit is related to the bedding of the rocks, and 

the same horizon is demonstrated to be ore bearing at other places near by. 

Sam I-I?:ll.-This prospect, which is immediately below the Key sandstone, and 

consequently near the top of the Ordovician beds, is of interest here as showing 

the vertical range of the ore bodies. It is situated in the SE. t sec. 13, T. 17 

N., R. 15 vV., about 500 feet above the level of Buffalo Fork. It is accordingly 

nearly 300 feet above the- Boat Creek mine, and over 300 fe~t above the Silver 

Hollow. The ore at the Sam Hill mine occurs in brecciated and fractured dolomite. The workings thus far are in rocks which show the action of surfaee 

waters, and accordingly there is · present a large . amount of ',silicate .and earbonate, although the original deposit was plainly zinc blende. 

Bonanza.-On Cow Creek, in the SE. t sec. 10, T. 17 N., R. 14 '\V., the 

Ordovician rocks have been extensively brecciated, and the displaced fragments, 

which vary in size up to several inches in length, qan be seen in the weathered 

exposures of the beds on the hillsides at many places. Brecciation has occurred 

at several horizons. The Bonanza opening is in such a bed, where the ore 

deposits for some reason have been localized. The working consists of an open 

cut in a shaft which has demonstrated a workable ·body. The ore consists of 

zinc blende associated with pink spar, sometimes occurring in large masses. It 

has been altered to loose secondary deposits of carbona~e and silicate. On this 

property a core drill has been used in prospecting. It is a light, portable 

machine, which cuts by means o1 chilled shot, and with it it has been possible 

to pass through the open ground, which would be difficult with other drills. 

The cores, from some of the boles were examined. They show plainly the 

brecciated condition of the ground and the extensive deposition of pink spar. 

The ore, as might naturally be expected, varies from place to place in the 

breccia, and the value of the drill is in determining where it occurs in workable 

quantities. 
78 ZINO AND LEAD DEPOSITtl OF NORTHERN ARKANSAS. 

Ohristie.-In the south part of sec. 19, T. 17 N., R. , 16 W., on Water 

Creek, considerable prospecting has been done in a bed of brecciated dolomite. 

The ore is principally zinc blende associated with pink spar. The extent of the 

deposit has not been determined, work being in progress at the time it was 

visited. The opening is in the upper /part of the Yellville limestones, and the 

ore-bearing bed is not unlike the ordinary brecciated deposits of the district. 

BAXTER COUNTY. 

The 1nines and prospects near Mountain Home, Baxte~ County, are all situ-

. a ted in the Yell ville dolomites. In this part of the field the Boone formation 

has been wholly remove~, and the upper portion of the dolomite series is likewise largely worn away by erosion. Prospecting in the southern part of the 

county adjacent to the area in which the Bbone formation is present has not been 

extensively carried on. It may be that this part will also prove to 'be within the 

mining district. 

Hawkeye No. 1.-This prospect is situated between East Pigeon Creek and 

.Baird Creek, in the NE. t sec. 1, T. 21 N., R. 13 W. Two open cuts have been 

made in the hillside. The rocks .which are exposed are more or less siliceous 

horizontal dolomites. They have been fractured and jointed, and in places brecciated. The ore at this place has associated with it quartz, lining the cavities 

and depsited on tlle surfaces of the rock. About 50 tons of crush rock carrying· 

blende and about 20 tons of fairly rich zinc carbonate ore have been piled up. 

Hulsenbeck.-These workings (Pl. XXVI, A), which are in the SW. t sec. 31; _ 

T. 21 N., R. 12 W., expose beds of dolomite which have quartz crystals deposited 

as a thin scale on the surfaces and in _cavities. The ore, which is principally 

blende, is found mainly on the quartz. Some of it has been oxidized to carbonate. 

There is also some secondary chert exposed in the workings, and this bears evidence 

in places of having been leached of its ore. Some carbonate has been shipped 

from this property. 

Gambetta.-This prospect sonsists of s.hallow shafts and a short tunnel, which 

is situated in the SE. i sec. 3, T. 20 N., R. 1_3- W. The ore, associated with 

quartz and .calcite, has the appearance of occupying a solution channel in the 

dolomite . . ...-

Lost mine.-The Lost mine is situated in the SW. t sec. 2, T. 20 N., R. 13 

W. It has produced principally galena. The workings consist of two open cuts 

in horizontal dolomites, which contain cherty beds. In the north cut a vertical 

fissure filled with broken dolomite and calcite is seen. It is apparently produced 

by a slight fault, which has a direction N. 80° E~· The shaft which is sunk at 

this mine cou]d not be examined because it was boarded up, but some ore has 

been found ir.. it, as shown by the rock on the dnmp. 


:MINES AND PROSPEC'.rS. 79 

Hopeful.-This prospect is situated in the· SW. i sec. 25, T. 21 N., R. 14 '\V . 

. The largest cut exposes a . bed o.f compact dolomite, but slightly fractured, underneath which is a second one of similar character. The bedding plane between 

them shows undulations. The ore is blende, with a little galena associated with 

milky calcite. The rocks have not been richly mineralized. No Clear structure 

could be made out which would account for the localization of the deposit. 

Bald Dave.-Bald Dave Mountain lies in sec. 11, T. 2 N., R., 14 W. On its 

northwest slope some blende and galena have been found, as well as zinc ca:rbonate, which has resulted from the alteration of the blende.' The ore is associated 

with calcite and some quartz. There are a number of other prospects at this 

mountain, in some of which there is a brecciated structure. 

Gold Stan,dard and Mark Hanna.-The Gold Standard is situated in the 

SE. i of sec. 30, T. 20 N., R. 14 W. The Mark Hanna is in sec. 29, close by. 

The rocks are even bedded; ~ut exhibit a slight dip to the northeast. The ore 

con8ists of zinc blende and carbonate associated with quartz. A considerable 

amount· of hand-picked ore is on the dump at the Gold Standard. 

Cedar Gap.-At this prospect, which is in the SW. t sec. 31, T. 20 N., R. · 

14 W., considerable development has been made, disclosing fractured and brecciated 

bed$ in open cuts, carrying zinc blende and zinc carbonate in openings of the 

rocks. The locality seems to be richly mineralized, and a good shipment of ore 

is awaiting transportation. 

Hawkeye No. ~.-This . prospect is similar in character to the one just described. 

It is in the center ~f sec. 31, T. 20 N., R. 14 W. The surface workings disclose 

principally 'zinc carbonate, which has resulted from the alteration of the blende, 

which is deposited in the fissures and crevices Qf the dolomites. 

Big John.-A number of open cuts which bear this name are situated in the 

NW. -!- of sec. 5, T. 19 N., R. 14 '\V. The rocks are dolomites, which contain 

cavities lined with quartz crystals. A small amount of zinc blende and carbonate 

is found associated with these druses. 

Wallace Knob.-Wallace Knob, near the center of sec. 33, T. 20 N., R. 13 W~, 

is crossed by a low ridge of brecciated material, which has a direction N. 60° E . 

. The brecciation is evidently due to the dragging of the beds along a fault plane. 

The prospecting thus fat has found a little blende and some pyrite, which has 

been altered in places to limonite. 

SEARCY COUN,TY. 

The development in Searcy County is near its northern' border, along the 

valley of Buffalo . Fork and its tributaries, especially to the east and west of St. 

Joe. Considerable prospecting has recently been ·done, and the building of the 

railroad will stimulate further work m thiR county. 

./ 
• 

80 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

TVinchester.-This property is in the SE. i sec. 2, T. 16 ~., R. 15 W. An 

open cut has been made in the bed of one .of the main tributaries of Rock Creek. 

The horizon is the upper part of the Yellville formation. The Key sandstone and 

the . St. tT oe member of the Boon_e formation are exposed at intervals along the· 

bluffs of the ravine~ sometimes only a few feet above the level of the water and 

dipping down to the bed of the branch, where the rocks have an undulating 

structure. . The ore of this place is a rich deposit of blende associated with pink 

spar. The rocks have been fractured and brecciated, and apparently the Win-. 

chester claim is about the horizon of a · number of prospects which have been 

more or less developed farther up on this same stream. It is one of the most 

promising localities southeast of Buffalo Fork. 

There are a number of prospects in the valleys tributary to Buffalo Fork 

from the southeast, but not very much development work has been undertaken. The 

Yellville formation is exposed in the immediate valleys of the streams, and prospecting has been carried on at horizons varying from a few feet to 200 feet 

below the Key :-5andstone. The elevation ahove the level of Buffalo Fork varie"3 

according to the dip of the rocks, and occasionally with definite faulting.. At some 

places ore is found in the bed of Buffalo Fork. At the mouth of a short hollow 

called Otter Slide a deposit of ore in breccia was seen. Near the mouth of , 

Spring Creek the Noxall ·prospect exposes a deposit of zinc blende associated 

with pink spar. . 

Jackpot (on Buffalo Fork).-High on the bluff on the wes.t bank of Buffalo 

Fork in the southern part of sec. 8, T. 16 N., R. 15 W., there is an opening 

under the Key sandstone which is known as the Jackpot. The ore at this place 

consists of small crystals of blende occurri~g in a mass of pink spar. The 

workings indicate that the ore and spar were deposited in a water channel. The 

distribution of the blende crystals in the spar, and the fact that there is but little 

zinc ore which is related to the country rock, favors this conelusion. Prospecting 

with a drill and by means of open cuts is being carried on adjacent to the 

,Jackpot and on the opposite side of the river at lower horizons. There is a fault 

plainly visible in the bluff a short distance down the stream, but thus far, as IS 

not uncommonly the ease in this region, no ore has been found which Is 

immediately in the zone of faulting. 

Near the mouth of Water Creek there is an opening in a brecciated bed of 

dolomite which exposes considerable ore associated with pink spar. Thi;;; prospect 

is not named, but is on what is known as the Jones property. 

, 11-lau/mee.-On the west side of sec. 12, T. 16 N., R. 16 vV., in the valley of 

Greenhaw Hollow, is a prospect known as the . Maumee. This opening is immediately below the Key sandstone, in horizontal beds of dolomite. The ore is 
MINES AND PROSPECTS. 81 

associated with pink spar, which appears to be deposit~d along the water channels 

and to some extent in jointing planes and bedding planes of the country rock. 

There are rich masses of blende in the crush rock upon the dump, but an examination of the tunnel indicated that the ore varied considerably in amount from 

place to place. Here, as at other places where the blende occurs in large 

masses, the ore is also found replacing the country rock adjacent to the main ore 

bodies. There is some carbonate and sllicate, as a result of alteration of the 

primary ore. A little chalcopyrite occurs as small crystals on the pink spar. 

This mineral has been altered by the same oxidizing solutions ·which have affected 

the blende . and given rise to greenish and bluish copper stains, which occur 

sparingly in the secondary zinc ores. 

J11.itd I-Iollow.- Along Mud Hollow the Ordovician rocks show some folding, 

and near the mouth of the hollow there is a fault, as shown on the geologic map 

(Pl. _ V). The p1·ospecting in this locality is in the west side of sec. 15, T. 16 

N., R. 16 W., distant from the fault, at a place where the rocks have been 

brecciated and fractured but not displaced vertically. The ore ~s associated with 

secondary chert and with dolomite spar. It consists of zinc blende, with some 

carbonate and silicate. Here, as at the Maumee, there is a moderate amount of 

chalcopyrite, and copper stains are in evidence on the secondary ores, as the 

result of alteration of this mineral. 

Excelsior (fm·merly the St. Joe).-On Monkey Run, just north of St. Joe, in 

the south part of sec. 7, T. 16 N., R. 17 W., considerable prospecting has been 

done near the St. Joe fault, and at the Excelsior a shaft house has been erected. 

There are some shafts immediately on the fault and . others to the north, where 

the rocks, although considerably fractured, retain a nearly horizontal position. 

The shafts which are on the fault have found but little ore with the exception 

of a small amount of carbo_nate and silicate occurring· in the material filling the 

fault zone. The fault zone is clearly indicated by what is locally known as a 

"marker." This is a mass of broken rock fragments cemented together, which, 

upon weathering, remains above the level of the surrounding beds as a rough, 

bowlder-like mass. In so far as has been made out it was not originally mineralized. Most of the ore thus far found is at a considerable distance from the 

fault, and consists of zinc blende associated with some pink spar deposited in 

small fra~tures, and does not, in so far as now known, occur in large masses. 

Apparently the expectation of those who began operations at this place was that 

they would find a rich ore body adjacent to the fault. Further prospecting may 

develop workable ore at this locality. 

Davy Orockett.-In the NE. t sec. 9, T. 16 N., R. 17 W., and in the N\V. t 

sec. 10, some prospecting has been done to the north of the St. Joe fault. As 

4538~~0. 24--04----6 
82 ZINC AND LEA.D DEPOSITS OF NORTHERN ARKANSAS. 

is the case neai the Excelsior, no ore has been discovered along the fault zone. 

"'\Vhat ore has been found is to the north, and is exposed in the open cut. It is 

zinc blende associated with pink spar, and it:l found in a fractured bed of dolomite. 

Big Iiitrricane.-In sec. 7, T. 16 N., R. 18 W., c~msiderable prospecting has 

been done on the upper part of Hurricane Branch. An east-west fault extends 

along the valley at this locality. The downthrow of the fault is on the south 

side, and brings the Boone flint in contact with the Ordovician. The ore thus 

far found occurs in the Boone adjacent to the fault, where, apparently as a 

result of the dragging. of the rocks at the time of displacement, brecciation took 

place. The workings consist of open cuts and a shaft, and drill holes have been 

sunk near by. The ore consists of zinc blende, with a large amount of carbonate and some silicate, as a result of the alteration of the primary deposit. The 

rocks in 'the open cut have a dip to the south, and the ore pitches with the 

rocks. Development at this place has not been very systematic. There is, however, an encouraging amount of ore in sight. By hand picking carbonate may 

be largely separated from the sulphide, but from the present workings the output of this mine would be mixed ore. 

NEWTON COUNTY. 

The mines and prospects in Newton County occur both' in the Boone formation and the Yell ville dolomites. The dolomites are found to be ore-bearing in 

the valleys of Mill Creek, Buffalo Fork, Davis Creek, and Cave Creek, while 

the developments in the Boone limestone are in the vicinity of Boxley, Jasper, 

and Cave Creek. 

Spier.-About 4 miles west of the Big Hurricane, on the same fault, near the 

center of sec. 9, T. 16 N., R. 19 W., is the Spier property. The displacement 

here, as at the Big Hurricane, brings the Boone chert in contact with the Ordo· 

vician dolomites, and the crushing of the brittle beds of the Boone has produced 

a fine breccia, which has been mineralized. A shaft (Pl. XXVII) has been sunk 

in the ore-bearing rock, and is apparently but a few feet south of the fault. The 

ore is zinc blende, excepting in the upper part of the breccia, and occurs in 

small and scattered amounts, uniformly distributed. The Boone has been so finely 

crushed at this place that the breccia, although consisting of practically the sam'e 

material as at the Hurricane, bears but ~ittle resemblance to the ore-bearing rocks 

at that place. 

In the valley of Shaddock Branch, intermediate between the Hurricane and 

Spier properties, some prospecting has been . done to the north of the fault zone, 

which has disclosed zinc blende in the . Ordovician dolomites. This prospecting 

is not extensive, but is mentioned here a>3 showing that to the north of the 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 24 PL. X 

A 

B 

0 

HAND SPECIMENS ILLUSTRATING GENESIS OF ORES. 
• 
MINES AND PROHPEO'.rS. 83 

fault, in the Ordovician rocks, where · they are relatively undisturbed, ore 1s 

found in very much the same horizon and attitude as to the north of the fault 

at Monkey Run. 

Jlfarble Oity.-In the S\V. t sec. 28, T. 17 N., R. 20 W.,, a short distance 

below the post-office of Willcockson, there is a prospect in the bed of Mill Creek. 

The rocks at this place are the upper portion of , the Ordovician dolomites, the 

saccharoidal sandstone being exposed on the bluff about 50 feet above. The 

development consists of an open cut, which shows considerable ore occ~n·ring in 

dolomites, with which are associated quartzose sandstone. T~e sandstone or sandy 

dolomite at this place apparently is an original portion of the dolomite series, 

and has not been infiltrated. It consists of material similar to that which composes the saccharoidal sandstone, but the quartz grains are in a matrix of dolomite: The ore-bearing bed is from 6 to 8 f.eet in thickness, and in working it 

Mill Creek has been diverted from its channel. There is some chalcopyrite associated with the ore, and the alteration of this has given rise to bluish and 

greenish stains, as a result of the small amount of' copper present. The rocks 

at this place exhibit fracturing and brecciation. There is considerable pink spar 

present. The sulphides have been partially . altered to carbonates and silicates. I 

There are a number of openings lower on Mill Creek, which show more or 

less ore in relations approximately the same as at the Marble City mine. 

Oanton.-In the SE. t sec. 6, T. 16 N., R. 20 W., considerable mining has 

been carried on, and a small crusher and hand jigs have been operated for concentrating the ore obtained. The deposit at this place, which is in and just 

below the bed of Mill Creek, has been worked · by means of a shaft and open 

cuts. The rocks show rich zinc blende, occurring in masses associated ·with pink 

spar, and there is c.onsiderable accessory ore, which has been deposited by 

replacement of the country . rock. 

W1:c1u:ta Belle.-This prospect is situated in the NW. i see. 12, T. 15 N., R. 

19 Vv., near the mouth of a short tributary of Cave Creek. It consists of an open 

cut in the bed of the stream, and shows zinc blende associated with pink· spar in 

a brecciated bed of Ordovician dolomite. The rocks in this vicinity show some 

divergent dips, but no structure outside of brecciation could be determin~d at 

the locality of the prospect. The zinc blende has been altered to some extent 

to carbonate. Not very much work has been done at this place, but it is probable that the brecciated bed could be more extensively developed. 

Old Granby.-ln sec. 35, T. 15 N., R. 19 vV., near the head of Cave 

Creek, considerable mining· was formerly attempted by the Granby Mining and 

Smelting Company. The rocks at this place are the upper portion of the Boone 

chert. The ore, which was obtained by means of shafts, is developed along 
84 ZINC AND LEAD DEPOSITS OF. NORTHERN ARKANSAS. 

fissures, and is found in material filling the fissures and replacing the country 

rock. Very little information could be oqtained concerning· the workings, excepting by examining the material on the dump near the shafts. 

Carbonate Nose.-In the northeastern part of the same section m which the 

Old Granby . shafts are located are some workings which show a considerable 

amount of carbonate. The ore obtained from them was reported, however, to 

have been principally blende, with some galena. 

Goswick.-In the SE. t sec. 3, T. 14 N., R. 19 W., there are a number of 

prospects and shallow pits from which carbonate and blende have been obtainrd. 

The surface of the Boone chert at this locality exhibits a number of fissures, 

and it is on these that the prospects are located. The ore found near the surface 

is largely carbonate, as ~ result of surface alteration. 

The prospects above described are quite different from those in the northern 

part of the district. They are in a different formation, and the rocks show a 

different type of structure. -The geology of this region has not been carefully 

studied, but there is considerable evidence of faulting, which extends "in a 

northeast-southwest direction. The fissures may or may not be related to ,this 

faulting. The f;lickensides observed indicate that the rocks have been under 

compression, and that movements have taken place in a horizontal plane. The 

faulting niay be of l~ter origin. The concentration of the ore in the upper part 

of the· Boone .must be aceounted for in a different manner from that which 

oeeurs in the Ordovieian. Erosion has but reeently removed the shales whieh 

formerly overlaid the Boone at this plaee, and suffi.eient time has not e~apsed · f9r 

the agencies- of weathering to have leached out the ore deposits, although this 

has taken plaee to some extent. It is probable that the accumulation of ore in 

. the upper horizon of the B9on·e was the result of the. coneentration of the 

original contents of the formation by eirculation under hydrostatic pressure. 

Panther Oreek.-In the NE. t see. 31, T. 16 N., R~ 21 W., near the head of 

Panther Creek, are a number of open euts, shafts, and tunnels, in the upper part 

of the Boone formation. The str~cture at this. place indicates that the rocks 

have been compressed and fractured. The slickensides observed indieate movement both i~ the horizontal and verti9al planes. The ore found is associated 

with the fractures, which have a direction of N. 30° E., and consists principally 

of zinc blende; but there is some carbonate, and a minor amount of silieate where 

surface waters have altered the ore. The ore runs in irregular sheets and masses, 

varying in richness from place to place, apparently with the width of the fissures, 

it also oceurs along the bedding planes laterally from them. Some galena is found 

assoeiated with the zinc. This is one of the well-defined examples of the association of ore with fissures, which seems to be the common case in the portion of 

the district where the deposits are in the Boone. 
MINES .AND PROSPECTS. 85 

There are a number of smaller openings and prospects in the vicinity of 

Panther Creek, but not very much development work hail been done on them. 

Chimney Rock.-In sec. 7, T. 16 N., R. 22 W., near the head of a tributary 

of Clifty Creek, there are some openings known as the Chimney Rock mine . 

. They are related to a fault, which may be seen traversing the Boone chert at 

this place. The walls are slickensided and give evidence of the movement of the 

rocks past each other. The amount of throw, however, could ·not be measured. 

Ore occurs in the broken chert and limestone filling the fissure. · This material 

is exposed at the surface along the line of the fault, standing up as irregular 

bowlder-like masses. The ore from this mine was principally galena. 

Baker & .McGratl~;.-ln the SW. i sec. 18, T. 16 N. , R. 22 W., ·on the east 

side of Villines Creek, there is a mine which is located upon a fissure. The 

workings consist of an open cut and a shaft (Pl. XXVI, B) located on the fissure, 

which has a north-south direction. A considerable quantity of crush rock is piled 

up near the mine. The ore is principally blende, although galena also is found. It 

occurs in the material filling the fissure, and the country rock for a short distance 

adjacent contains accessory ore deposited by replacement. 

Bonanza.-This property is similar to the one above described in the character 

of its ore and the structure of the rocks. 

Ponca City.-This prospect is situated in the SW. t sec. 24, T. 16 N., 

R. 23 W. Prospecting was done here some years ago, and at the time the place 

was visited work was in progress on an open cut, · from which considerable ore 

was being obtai~wd. The ore originally consisted of blende, with some galena, 

but has been largely altered to silicate and carbonate.· Occasionally the carbonate 

is stained with cadmium, giving rise to the variety known as "'turkey fat." An 

examination of an old shaft and tunnel at this place shows that the ore body, is 

apparently related to fracturing or faulting, which has a direction of N. 20° E. 

Bennett.-In the S\V. t sec. ·26, T. 15 N., R. 23 W., are a number of shafts 

and open pits from which ore has been obtained. At the time they were visited 

no work was being done. Th@ material lying on the surface indicated that the 

ore was largely; carbonate. The deposit is apparently related to jointing · and 

fracturing, which has a direction of N. 45° E. Some ore has· been shipped from 

this mine. 

SUGGESTIONS FOR PROSPECTING AND MINING. 

While the study of the district allows certain inferences to be drawn which 

may be of value in prospecting and in working the ore bodies already located, 

each individual case requires judgment and experience, since there are so many 

factors involved. Naturally there is no better rule than the common one ·of the 

miners, which is to follow the ore. In doing so the structure of the rocks at a · 
86 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

given locality should be studied and the general character of the deposits should 

be determined. The classes of deposits outlined in this paper, while they a~e 

intended to explain the genesis of the ore, may be applied by the practical 

miner to the deposit which he is working. 

Thus far the principal difficulty encountered in the district has arisen from 

the mixed nature of the ore found in surface workings. The oxidized ores are 

associated with the sulphides and can not be readily separated, so that the eoneentrates are mixed. Men experienced in handling sueh ores, however, meet 

with a fair degree of success by remodeling the mills and reworking the ore. 

As the production increases, it is probabl~ that smelters will be erected whieh 

will handle . mixed o~e, since this has . been done in other. fields. At the present 

time the ores are for the most part purehased by firms engaged in the manufacture of zine oxide. As the mines are carried deeper, or under sufficient cover, 

oxidized ores give way to the sulphides, and clean eoncentrates are readily 

obtained . . ' 

Certain of the deposits produce almost wholly sulphide ore. In them the 

only difficulty ordinarily experienced is that of finding large and continuous 

bodies. 

The variation in the richness of the bedded breccias has already been alluded 

to. Sometimes there is an abundance of pipk spar., but no ore. Persistent 

prospecting at these localities usually results in finding more ore, although some 

of the workings have been abandoned because they are too lean to work 

profitably. 

At the present time there are a number of large mills in the district and 

relatively few hand jigs. ~t is a well-aceepted fact that ore can be profitably 

concentrated with ~and jigs, and where there is any uncertainty . as to the extent 

of the deposits it would be well to work them with an inexpensive equipment 

until there is a sufficient amount of ore in sight to justify the erection of a mill. 

There are certain mills already built which are situated so that they could profitably be run as custom mills, and where experienoe has shown that the deposits 

which are intended to supply them are not sufficiently rich to demand their full 

capacity they could be profitably employed in doing custom work. 

A favorable point in the Arkansas district is the. absence of water in most 

of the mines. This is due to the fact that many of them are located on slopes 

and hillsides, so that the workings are drained. On the contrary, however, it is 

occasionally difficult to find or store a sufficient amount of water for the milling 

operations. This difficulty can usually be overcome by choosing a location for 

the mills a short distance from the mine. In some instances it will be necessary 

to .pump water to the mills. 
LEAD .AND ZINC DEPOSITS OF NORTHERN .ARKANSAS. 87 

OPINIONS OF PREVIOUS 'VRITERS.a 

In the previous reports on the northern ' Arkansas field certain ideas have 

been advanced which are not accepted by the writer. These pertain largely to 

theoretical considerations, and some of them deal with geologic facts. Professor 

Branner, in describing the breccias, states that the bedded breccias were not 

formed on fractures, but along ancient underground watercourses. It is apparently his belief that the dissolving of the dolomites caused the rocks th collapse 

along the water channels, and thus form the mass of irregtllar fragments which 

constitute the breccias. An examination of the pieces which constitute the 

breccias shows that they are angular, and have suffered relatively little solution. 

The writer has argued that these breccias were produced b)~ the differential 

movement of the strata which caused the fracturing of the rocks and the shearing 

of the pieces past one another, so that they were more or less rotated from their 

original positions. The breccias when once formed were sufficiently open to afford 

channels for the circulation of the ground ~ater, and it was due to this fact that 

the. cementing material was introduced. The matrix of the breccias consists 

largely of pink spar, with which was deposited more or less ore. 

I ' 

Professor Purdue, who had studied . the field previous to the work done for 

this report, had reached the conclusion that the breccias were due to fractures, 

and during the progress of the summer's work his opinion was strengthened by 

his observations. His conclusi_ons, which were .reached independently, are recited 

h~re in confirmation of those of the writer. However, at certain places in the 

field, especially in the lower horizons of the Boone formation, therre is definite 

proof of the collapsing of the rocks adjacent to sink holes and solution channels. 

Some of these localities have been prospected: Tf!ey are distinct in character 

from the breccias, and are recognized ,by the miners in the district as old caves 

or sinks. They usually contain a large_ amount of clay, and the relation of the 

undisturbed rocks adjacent to them is clear proof of their manner of , origin. 

Mr. Bain, in speaking of the breccia deposits, considered them t~ have been 

formed along zones _of pressure, and accordingly to have their greatest extent in 

the vertical rather than the horizontal plane. He also, mentions limestone conglomerates as occurring in. the district. Careful study of numerous localities 

failed to show the existence of such conglomerates, and it is the opinion of the 

writer that the l)eds observed were probably breccias. · The relation of the$e 

a Branner, J. C., Zinc and lead deposits of northern Arkansas: Ann. Rept. Arkansas Geol. Survey for 1892, vol. 5, 1900; 

also Trans. Am. Inst. Min. Eng., vol. 31, p. 572. 

Bain, H. F., Preliminary report on the lead and zinc deposits of the Ozark region, Twenty-second Ann. Rept. U. S. 

Geol. Survey, pt. 2, 1902, pp. 195-202. 

Van Rise, C. R., and Bain, H. Foster, Lead and zinc deposits of the Mississippi Valley, read before the Institution of 

Mining Engineers at the general meeting at London, May 29, 1902: Excerpt from Trans. Inst. Min. Eng., pp. 34; 35 . 

• 
88 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

so-called conglomerates to the brecciated beds, and the importance of bedded 

breccias, does not seem to have been n~cognized by Mr. Bain. 

In regard to the faulting of the region, the writer presents an interpretation 

which is decidedly opposed to the one given by Professor Brauner. In Professor 

Branner's report, certain of the more important faults are figured and de-,cribed 

as thrust faults. Careful study of the relations of the rocks, as well as the hade 

of the fault planes and fault fissures, shows that the displacements are normal in 

most cases. Because of the large amount of detrital material on the slopes, the 

exact relations of the beds along the line of the faults are not always determinable. However, the sagging of the rocks on the downthrow side is readily seen 

to be the greatest at the point of maximum displacement, while on the upthrow 

side the strata usually retains relatively the same level throughout the extent of 

the fault. 

There are certain places in the field where thrust faulting was observed. It 

did not give rise to definite lines of dislocation, but resulted rather in' buckling 

an~ crushing of the strata. The normal faulting is regarded as having taken 

place subsequent to the compression which produced the brecciation, and as being 

due to a readjustment following the stresses, or to later oscillations of level of 

the formation.s of the region. 

In regard to the theory of ore deposition, there are likewise certain differences 

of opinion. These differences are largely theoretical, although they pertain in 

some degree to the economic development of the field. Professor Branner 

described bedded deposits which he thought were contemporaneous with the rocks 

in which · they occur. The ore bodies which he placed under this class are 

believed by the writer to· be due to secondary alteration and replacenl.ent of the 

rocks. An examination of prospects, which are characterized by secondary chert, 

shows that in many cases the original bedding of the dolomites has been retained 

in the structure of the chert. 

Mr. Bain has given considerable prominence to what he called disseminated 

ore in compac.t limestone and unbroken conglomerate. The writer failed to 

observe any ~eposits which could be characterized by this description. It is his 

opinion that the conglomerates mentioned by Mr. Bain are really of the nature 

of breccias, as above pointed out. At a number of places where the ore bodies 

are rich the recrystallized country rock carries more or less ore. Such occurrences 

have been designated in this report as accessory ore, and it is not improbable 

that it is this type of deposit which was referred to by Mr. Bain as disseminated 

ore in compact limestone. 

In the discussion of the ore deposits of the Mississippi Valley ·Mr.. Bain and 

I 

Mr. Van Rise have argued that the ·probable source of the ores is the Ordovician 

.. 
OPINIONS OF PREVIOUS WRITERS. 89 

dolomites, which m northern Arkansas are included in the Yellville formation. 

While the writer has taken a position which does not preclude this possibility, he 

has also shown that the circula~ion of the ground water has been largely a 

downward moveme.nt, and he is inclined to the opinion that it is this circulation, 

rather than the movement of solutions under hydrostatic pressure which has given 

rise to the ore bodies. The ore has no doubt been in part concentrated from the 

Ordovician by the downward · movement of . solutions, but the formation which 

apparently has been most extensively leached of its mineral contents is the Boone 

formation. This is known to be ore-bearing at a number of places in the Arkansas 

field, and in the Ozark region in general it is a source of ore. Wherever ore 

deposits are found in the Yell ville formation, the Boone has previously been 

present. over it. Its superposition, and the presence in it of lead and zinc ores, 

,together with the fact that it has been wasted under the influence of atmospheric 

agencies and leached by ground water, ·would seein to make this opinion altogether 

a reasonable one. 

Ore deposition m the Ozark region, and in the Mississippi Valley in general, 

although controlled by the same general principles, has occurred under varying 

conditions; and it seems reasonable to expect that while there are in 'the various 

districts many similarities, there should likewise be important differences~ and, 

accordingly, no general theory can be offered for the entire area. Thus far the 

northern Arkansas district appears to warrant consideratio'n as a distinct field, as 

it is not a counterpart of any district which has been described. 
DETERMINATION AND CORRELATION OF FORMATIONS. 

By E. 0. ULRICH. 

Several weeks of the summer of 1902 were spent in collecting stratigraphic 

and faunal data relating to the geol~gic formations of northern Arkansas, and of 

the Yellville quadrangle especially. Most of the field work was carried on in 

company with Mr. George I. Adams, who was in charge of the survey of the 

quadrangle. After working out the section in that area, Marshall, Eureka 

Springs, Fayetteville, and several localities in the vicinity of Batesville were 

visited. All of these are type localities of formations named and described in 

the reports of the Arkansas geological survey. 

In every case the lithologic and stratigraphic characteristics of the formations were carefully studied, and in most cases large collections of fossils were 

secured. Since returning from the field these fossils have been sorted · and 

determined in some cases very thoroughly, ..so that the ~ritei· feels reasonably 

confident of the correctness of the correlations based chiefly upon them. In 

formulating conclusions, however, all available evidence was duly considered, 

nearly as much reliance being given to lithologic pecul~arities and stratigraphic 

relations · as to faunal aspects. 

Beginning 'with the lowest, the following lithologic formations are distinguished: Yellville limestone, Key sandstone, Izard limestone, Polk Bayou lime-

::~tone, St. Clair formation, Sylamore formation, Noel shale, Boone formation with 

the St. Joe limestone member at base, Moorefield shale, Batesville sandstone, 

·Fayetteville formation, W edington sandstone, Pitkin ·limestone, ·Morrow formation, and Winslow sandstone. The relations of these formations to one. another 

and to stratigraphic divisons proposed by previous authors, and also the 

respective positions of the formations in . the time scale, are shown in the 

accompanying correlation table. 

90 
I 

' 

n 

:.. 

0 

Ill 

"" f;r;. 

z 

0 

::c 

o:; 

.-: 

-

z 

< 

% 

0 

> 

r.l 

A 

I z 

< 

~ 

' p 

~ 

I J:. 

I 

z 

~ I 

> 

0 

I 0 

o:; 

I 0 

00'1'7'elation trihl of tlte R leozo 'c formation:s iJn northern Arkansas. 

-- - -- ~1 PP ULE LrTROL I EQUIYALE.· r . F Rl\lATJ LW Y PRESENT IN NORTH- TA.'DARD TIME 'AI.E F THE HTOAN PROYINC'b:. 'onTHERI\ RK.\ ' E.RN ARK AN 'EC'TJON . 

- - -

~i I Lat P t viii Win low formation. I 

a '' in low formation. 

I .:::·~ -

I,_. 

}::Srly Pot ,.me. Morrow f rmation. pp r part f i rrow formation. 

-- -

Pitkin lim n. Pitkin lim tone. ~ I 

I 

I 

I 

I 

I 

-

I 

I 

I 

I 

l 

I 

I 

:id -- -- Bird ville. w ington sand ton c :! r.: ,..!:C Fa ' ttevill hal. I .s (/J 

CIS . Fayett vill formation. I Q) ~ Tribun . 

I 

-;:. - -- ypre 

Ba ville sand ton . Bat vill and tone. 

.~ te. enevi ve. ~ -- - .t:- I :\1oor field hal (including Spring~ ~ , t. Loui. b limestone). 

:~ l 

Q) -- - ----- E :::; ~ • p rg n Hill. 

I <1) - (Wanting.) ~ \\ arsaw. I 

- - --- Q.) I K oknk. reater ~art f b r y Bon lime tone. 

Boon -- --- rherty lim tone. 

~ I Bnrlinaton. lim tone. Gra_t ub ry tallin lim ton pp r part of t. J lim 0 t. oe lime t ne. ton 

----- -- - -

Kind rh ok. oel hal . 

i I .s I hemun ~ ylamore foro ation. 

~~ I Portag q_ - --- )J -Devonian. (Wanting.) 

Eo-Devonian. 1-

Helderbergian. 

ayu an. ('\\ antin . ) 

I "Niagara." g,~ .g d I ~ linton. t. Clair lim ton. 

Cason hale. 

Richmond. ~ Polk Bayou lim tone. 

- ~ g Lorrain . Izard lime tone. ~ 

] Eden or Frankfort. ;;.,) 

Utica. 

g Trenton. I (Wantin .) 

~ 1 

Black River. 

~ 

~ ' 

ton River. 

I • I t. Peter. Key sand ton I ? Lower part_of K ~nd ton t::;"" 

~.(;! 

~ Shakop Yellville lim tone. 1 Yellville lime ton . Oneot.a. 

mbrian. 

aThe term "late Pottsville," a d by the author, refers to the Pottsville above Mr. David White' ewanee 

tag , which, together with all known Penn ylvanian beds beneath it, i here included in the "early Pot vill ." 

b The prevailing opinion to the t. Louis, p rgen Kill, and Warsaw that, while they are not trictlr contemporaneou , they are till merely local developments of two or three par of a illgle formation, usually ailed 

t. Loui . The writer' work, however, bas shown that they are readily di tingu bable lithologic units, two of them 

having a wide geographic d' tribution, and all three occupying definit and di. tinct positions in the tratigrapbic 

column. Together tb y constitute a group for which the name 1\!eramec, after th river of that name in l\11 uri, 

where all three divi ·on may b een, is cho en. 

c Th reader i referred to tb di ussion of the Wedington ndstone for Mr. !rich' interpretation or the rela· 

ti n of th · sandstone to be Fayetteville hale. 

4538-Ko. 24-04. (Far pag 0. ) 

- --

FoRM.ATION FTEN W ANTINO, IN WHOLE BRANlii'ER AND WILLI M ' ECTlON, PUBLI BED I • REPORTS 

OR IN PART, OR DEP ITED ONLY IN OF GE LOGI AL RYEY F ARKA~ 

LOCAl· TRo OB . 

. .: ~ i I Millstone grit. 

~~·~ bales and sandstone. 

Two ba al member of Morrow formation. Kessler limestone, Coal-bearin~ shale, P nUpper~1tkin often removed by ci. tremitallim tone, and Was ington hal 

= "'-and sandstone. 0 erosiOn. ~- So Archimedes limestone. 

$:! 

hale and 'V edington sandstone. 

.s • haly sandstone.d 

Upper IX) 

0 

I=Q Ma hall hal ·' 

00 

p 

Basal portion of Batesville and tone. ~ .~ Bate ville sand tone. 

z :~ I 

0 I Spring Cr ek lime tone. l):l 

MOorefield shale and Spring Creek lime- ~ .~ stone. 0 ~ Fayetteville hale.! 

Wyman sandston . q 

....,..,.. 

Upper part of cherty oon limestone. Q.)<1l...,s : Boone chert. ~~ ..... io~ I Carrollton limestone. 

Basal part of t. Jo lime tone. o~.g t. Joe marble. 

I oelshal . Eureka hal (typical). 

---~ 

ylamore formation. 

:i 

< 

z y lam ore s."l.nd tone and bale: (Eur ka hale in 0 part. ) > 

A "" I 

:i 

< 

~ 

~ 

~ t. lair lim ton 

ri3 - t. Clair lim ton . Cason hal . ~ 

- -· 

'~ 

Cason shale. - Polk Bayou limestone. 

Polk Bayou lim ton 

~ 

Izard lim tone. ·~ 

~ 

~ 

·~ Izard lime tone.h 

:i .s 

~ 

0 > ---

~ 0 

---;-

Ky nd ac haroidal ,and t n ton . ~ 

~a.; 

--- and ";::;~ ? Top of Yelh·ill lim t n . Magn ian lim ton 

,...,.., ........ ...... -· 

th W ington sand. t ne, which imond . in bl r port ll Wit bin t n ounty, 

I 

I 

l 
DETERMINATION AND CORRELATION OF rFORMATIONS. , I 

91 

DESCRIPTION OF CORRELATION TABLE. 

The above tabular arrangement and correlation of the lithologic units or 

formations which it is proposed to recognize in mapping northern Arkansas and 

southern Missouri (secqpd column) bring out in ·a. graphic manner their relations 

to all th~ time divisions so far reeognized in the ea~tern hal£ of the interior 

continental or ''Mississippian province." ct The Ordovician portion of the scale . 

is in accordance with the latest revisions of the sections in New York, Ohio, and 

Tennessee. The Silurian and Devonian follow the New York section, except that 

the divisions usually recognized beneath the Clinton are omitted. The Mississippian 

is, according to the section in the Mississippi Valley, wo:r;ked out and soon to be 

published by the writer. b 

The upper Mississ_ippian is given m full, because this portion of the Paleozoic 

section is best developed in northern Arkansas. 'lt is perhaps unnecessary to 

add that the author has n~ intention of intimating that the time terms printed 

horizontally are even approximately coordinate. That might be claimed only for 

the names in the Mississippian portion above the Kindm;hook. As to the rest, 

where the Arkansas section is incomplete it was thought sufficient to use terms 

of higher values only. 

The third column shows- the formations and parts of formations that, so far · 

as observed, occur throughout the region. In the second and fourth columns 

are shown the portions of the complete 'section that, so far as observed, are 

missing always in Arkansas, and tho~e parts that were laid down only locally in 

embayments of old shore lines. The fourth column shows also the overlapping 

formations that were laid down in extending seas and are more and more 

incomplete basally in the higher parts of the ancient Oz~rk land mass; it shows 

also those formations of which the upper portions were in places eroded. The 

fifth column, , finally, shows the classification used in the latest reports of the 

Arkansas geological survey. 

a By this term is meant the area covered by a great though frequently modified inland sea that in Paleozoic time 

occupied more or less of the territor~~ lying between the Rocky Mountains on the west and the Appalachian Mountains on 

the east. The name Mississippian was applied to this sea and province by Walcott (Proc. Am. Assn. Adv. Sci., 1894) and 

adopted by Ulrich and Schuchert in the~r recent preliminary discussion of "Paleozoic seas and barriers in North 

America" (Rept. New York State Paleontologist, 1902). The term, however, i3 confusing, since it has a fixed application 

to the Lower Carboniferous rocks of America, and therefore its use as a denomination of a sea ought to be restricted to 

the waters in which the Mississippian series of rocks was deposited. It is also unsatisfactory, since in only a few cases do 

Paleozoic formations of the eastern half extend west of the Ozark uplift. The only one coming to mind now is the 

Richmond. All or nearly all of the other formations can be definitely placed either in the eastern or in the western 

division. It is suggested, therefore, that the Mississippia.q province be divided into two provinces, the easternmost or 

Kankakee axis of the Ozark uplift being the line of .separation in some cases, the main Ozark axis iu others. For the 

eastern division the name Ohioan province· is suggested. On the east it was bounded during the Ordovician, Devonian, 

and Carboniferous by the Appalachian Valley barrier, and during the Silurian in part by the same barrier aud in pa1,:t by 

the Helderbergian _barrier. These two barriers separated it from the Atlantic waters in the Appalachian province. As 

the western division requires further study before it cau be definitely decided that it is not again divisible, into a northern 

and a southern province,. no name is proposed. 

bl'he lead, zinc, and fluorspar deposits of western Kentucky (in preparation). 
92 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

Stratigraphic unconformities; when general in the area under discussion~ are 

denoted by a wavy 1ine drawn entirely across the fourth column of the table, 

either beneath or above the formation name. Horizons of occasional unconformity are distinguished by the wavy line b~ing drawn only half across the 

column. 

Beginning at the bottom of the column the first stratigraphic unconformity 

. shown, except where the Key sandstone has been removed entirely, occurs between 

the Key sandstone and th~ Izard limestone, the interval represented by the 

unconformity at its shoi'test being equivalent to the Stones River, Blaek River, 

Trenton, and Utica ages. As a rule this interval persisted through the remainder 

of Ordoyician time and through all of the succeeding Silurian and Devonian, the 

first deposits to cover · the eroded Key sandstone or, if that is wanting, the Yellville limestone, being either the Noel shale (as at Eureka ·Springs) or some part 

of the St. Joe limestone member of the Boone formation of the Carboniferous 

system. 

The six formations intervening between the Key sandstone and the S~. Joe 

limestone member (see table) are all more or less local in their distribution. The 

Izard limeston3 and the Sylamore formation· are more extensive than the others. 

The Izard and Sylamore were laid down over a more nearly base-leveled submerged land, while the Polk Bayou, Cason, and St. (nair seem to be restricted to 

comparatively · limited, shallow troughs causing narrow indentations of the old 

shore lines. As may be expected, therefore, t}le most convincing evidence of 

unconformity seen in the field occurs along the borders of the areas containing 

the Polk Bayou and St. Clair limestones. The St. Clair is even more restricted 

in extent than the Polk Bayou, and in the borders of the troughs in which both 

occur the effect of erosive agencies is more obvious than in their central parts, 

to which, as a rule; the St. Clair limestone is limited. 

The upper surface of crystalline limestones, such as the Polk Bayou, always 

breaks up into bowlders or becomes strongly undulating under ordinary processes 

of weathering. From observations made in the vicinity of St. Joe, Ark., it is 

evident that this limestone weathered in Silurian and -Devonian times just as it 

does now, the top of the Polk Bayou, where it is covered by the shales of the 

Sylamore formation, showing roughly rounded prominences 2 to 3 feet in height. a 

The other unconformities are not so clearly defined structurally, first, because 

the erosion did not for various reasons :result in so uneven a surface as that of 

the Polk Bayou and to a less extent of the St. Clair limestone, and, second, the 

· greater or smaller remnant of the Key sandstone, which usually occurs between 

the Yellville limestone and the Noel shale or St. Joe limestone member (the 

a A fi~e section showing such a contact occurs in the railroad cut one-half mile northwest of _St. Joe, Ark. 
DETERMINATION AND CORRELATION OF FORMATIONS. 93 

intervening formations being abs_ent) is . broken up into a sand and redeposited 

so as to f'Orm a level floor for the succeeding sediments of the Carboniferous, 

which in these cases come next. This condition is shown very clearly at Eur~ka 

Springs b~neath the typical exposure of the Noel shale (Eureka shale of Branner). 

Here the unconformity is beneatli the thin bed of material which caps the 

Ordovician dolomitic limestone, and which has been. called "'Saccharoidal sandstone." This reworked deposit accordingly does not represent the Key sandstone 

of other sections, but is . a much younger _formatiOn-possibly early Mississippian 

in age. 

Where the erosion was not deep and left a considerable portion of the Key 

sandstone, as originally deposited, the reworking and leveling of the loose sand 

grains could scarcely have f_ailed to completely obscure aU satisfactory evidences 

of unconformity, so that, even with good exposures, it would be almost futile 

to · look for them. In these cases paleontology or stratigraphic position only may 

be used in demonstrating the hiatus. 

EVIDENCE UPON WHICH THE CORRELATIONS ARE BASED. 

The fossil contents of a formation can not be discussed satisfactorily without 

ample illustration. Good figures tell their own story, and therefore furnish independent evidence upon which the experienced paleontologist may rely chiefly in 

summing up the evidence presented by an author. 'Vithout them the, reader is 

obliged to depend solely upon lists of fossils, and the value of these, naturally, is 

in proportion to the experience and ability of the author in making exact specific 

·discriminations. In making stratigraphic correlations the · paleontologist often 

depends largely upon evidence furnished by undescribed species and varieties 

which are found in the beds that he is endeavoring to classify, and which perhaps 

may be known to him alone to occur also in the well-known or at least betterknown formations with which he correlates the horizons in question. This 

evidence, which it is difficult under any circumstances to present satisfactorily, 

may, indeed, be of paramount importance in demding the question of equivalence. 

The last consideration is furnished in several instances by the Paleozoic section in 

northern Arkansas, notably the Yellville, Polk Bayou, Batesville, and Fayetteville 

formations. 

ORDOVICIAN FORMATIONS. 

Yelwille limestone.-The fossils found in this formation m northern Arkansas 

and southern Missouri indicate at least two distinct horizons--a lower one with 

fossils comparatively rare and poorly preserved, and an upper one, so far not 

recognized in northern Arkansas, containing better and more abundant specimens 

and more species. Besides these there seems to be a third horizon, comparable 
94 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

with the F<yt Cassin bed of the Beekmantown in Vermont, and probably holding an jntermediate position .between · the other two. The lowest horizon occurs 

beneath the "Second Saccharoidal" sandstone, which is occasionally recognizable in 

northern Arkansas, 200 or 300 feet beneath the upper, or First Saccharoidal, which 

Mr. Adams proposes to distinguish as the Key sandstone. Still, there is considerable doubt respecting the exact positions of t~e ,lower and supposed middle 

fossiliferous horizons, and some careful stratigraphic and paleontologic work, 

involving the Calcife~ous rocks of the whole country, must be done before it 

will be possible to suggest a satisfactory and approximately permanent classification of these early Ordovician rocks. 

The fossils of the beds under consideration consist chiefly of molluscs, with 

occasionally a few brachiopods and trilobites, and more rarely a sponge or 

sponge-like coral. Bryozoa are wanting entirely. The specimens, especially in 

the two lower horizons, are nearly always silicified and generally embedded in 

chert. Many of the species are new, and some are not yet determined, but the 

following partial list of species collected from the two lower horizons in Arkansa8 will probably suffice to establish the age of the formation: 

Tryblidium ovatum vVhitfield. 

? Ophileta nerine Billings. 

? Ophileta disjuncta Billings. 

Eccyliopterus triangulus (Whitfield). 

Straparollus intralobatus Sardeson. 

Raphistoma minnesotensis (Owen ). 

? Pleurotomaria? postumia Billings. 

Fossils of Yellville formation. 

Murchisonia putilla Sardeson. 

Murchisonia argylensis Sardeson. 

Hormotoma artemesia (Billings). 

Holopea? obesa Whitfield. 

Subulites exactus Sardeson. 

Orthoceras lamarcki Billings. 

The apparent absence of the ,?-pper or Shakopee fauna a in the Y ellvHle 

limestone possibly is due to the absence of that horizon in the Magnesian limestone series in northern Arkansas. In that case the Yellville limestone would 

almost certainly be equivalent to the Oneota limestone of the upper part of the 

Mississippi Valley, in which most of the fossils of the above list occur. The 

Key sandstone in that case might be regarded as an increased development of 

the New Richmond sand:::;tone of Wisconsin and Minnesota, which there separates 

the Oneota from the overlying Shakopee. It is very doubtful, however, if thfs 

view of the Yell ville limestone can be J. ustified. On the other hand, the fact / I 

that the Sh.ft.kopee fauna occurs in excellent development beneath a sandstone 

that can not be distinguished from the Key sandstone at a locality in Christian 

County, Mo., less than 60 miles northwest of Yell ville, renders it highly 

probably that this fauna is included in the Yellville formation and was merely 

a This fauna has been partially worked out by Sardeson in hi3 paper on The fauna of the :Magnesian series: Bull. 

Minnesota Acad. Nat. Sci., vol. 4, No.1, 1896, pp. 92-105. 
DETERMINATION AND CORRELATION OF FORMATIONS. 95 

overlooked in the rather hurried search for fossils in the vicinity of Yell ville. 

Besides, on account of the abundant waste from the overlying sandstone, outcrops 

of the horizon a;re comparatively infrequent. Again, it is a well-known fact that 

in magnesian limestones the faunas are very unequally distributed, and generally 

restricted to thin, intermittent bands, so that they may not only be easily overlooked in any given section, but may be absent locally. 

The base of the Yellville limestone has not been determined, but as described 

by Mr. Adams it includes only beds of Ordovician age. As the lowest rocks in the 

Yellville quadrangle are very near, if not beneath, the base of the Ordovician, 

his definition amounts practically to saying that the Yell ville is limited below by 

the base of that system. The divisional line between the Ordovi<~ian and -the upper 

Cambrian, however, is very indefinite nearly everywhere in America, and it will 

therefore be no easy matter to fix the basal limit of the formation. In the writer's 

opinion the formation should extend downward to. the first unconformity~ or to 

the first important lithologic change, beneath the strata exposed in the type locality. 

If the extremely cherty lower fossil horizon near Yell ville is, as appears highly 

probable, the equivalent of the Potosi limystone of the lVlissouri section, then the 

base of the formation is likely to c<?rrespond with Nason's "Edgewise bed" of the 

same section, and thus include-like the ''Magnesian series" of the upper Mississippi Valley, the Arbuckle limestone of Indian Territory, and the Knox dolomite 

of the Appalachian -region--upper Cambrian as well as lower Ordovician strata. 

According to this conception, the Yellv'ille limestone embraces the interval represented in Missouri by the formations intervening between the base of the Crystal 

City or St. Peter sandstone at the top and the unconformity marked by the 

limestone conglomerate occurring in the shales and shaly limestones which separate 

the · Potosi limestone from the middle Cambrian limestone at Bonne Terre. It 

becomes, then, also the exact, though thinner, equivalent of the Arbuckle limestone 

of Indi~n Territory and Texas . . 

. Key sandstone.-Th~ only fossil remains observed in this sandstone are of a form 

of Scolithus. The vertical tubes vary from 1.5 mm. to 2.0 mm. in diameter, are 

n~arly straight, and pass entirely through layers 6 to 8 inches in thickness. 

The age of this and equivalent formations could not be established if faunal 

evidence alone were depended upon, since their fossils are extremely ra,re and, in 

consequence of the nature of the sediments, very poorly preserved. The stratigraphic position and unilsual lithologic character of the Key sandstone, however, 

furnish criteria that are believed to be incontrovertible. In the first place the 

constant position of the sandstone next above magnesian limestones, which, 

when they are at all fossHiferous, always hold the highly characteristic Shakopee 

) 
9.6 ZINC AND L.EA.D DEPOSITS OF NORTHERN ARKANSAS. 

fauna, definitely fixes the older limit of "its age. In Minnesota, Wisconsin, Iowa, 

and Illinois, the St. Peter sandstone holds precisely the same position, while in 

Missouri the same interval is occupied by the • • First Saccharoidal" or Crystal City 

sandstone, and the Cap au Gres sandstone. The last is another and more recent 

name applied by Keyes a to the same formation in the Hannibal, Mo., and Calhoun 

County, Ill., uplift which crosses lVIississippi River above the mouth of Illinois 

River. A8 the term Crystal City sandstone is the first geographic name applied 

to the formation in Missouri, it is to be understood that when that name occurs 

in this discussion it refers to all the outcrops in the State that can be correlated 

with the sandstone at Crystal City. 

The equivalence of the St. Peter and Crystal City sandstones is established 

by not only the rocks beneath them, but also by the age of the oldest rocks 

above them. The rocks immediately overlying th~ Crystal City sandstone in 

Missouri vary considerably, it· is true, at different localities, ranging from oldest 

Stones River to the St. Joe member of the Boone limestone. This. variation is 

due chiefly to nondeposition of the intervening formations, but doubtless also 

in part to pre-Carboniferous erosion. Still, where the section is most complete, 

the Crystal City sandstone is follow~d, apparently quite conformably, by the 

''First Magnesian" or Joachim limestone, as ·it is called by Winslow, and this, 

unconformably, as the writer was recently enabled to establish in Ste. Genevieve 

County, Mo., by rocks equivalent to the Ridley limestone of the Stones River 

group in Tennessee. In the upper Mississippi Valley, as a rule, the section 

above the St. Peter sandstone appears not to begin with a well-defined horizon 

that may be correlated with the First Magnesian in Missouri, but in most cases 

observed by the writt;-r the St. Peter was succeeded unconformably by strata of 

Stones River age. 

In other places, however, especially near :Mississippi River, from a few 

inches to perhaps 4 or 5 feet of greenish shale or clay intervened between 

the top of the St. Peter and the base of the Stones River. This greenish shale 

bed is the only stratum in the upper Mississippi sections that can be correlated 

with the Joachim limestone of the Missouri section. The suggested correlation 

is rendered at least probable by the fact that (1) the Joachim lime:stone, occasionally at least, contains considerable clayey matter, and (2) nothing of essential 

importance antagonizing the view is known. 

Recapitulating the stratigraphic evidence, it is seen that the Shakopee occurs 

next beneath both the St. Peter sandstone and the Crystal City sandstone. Next 

above the Crystal City sandstone is the Joachim limestone, followed unconformably by early middle Stones River limestone; and above the St. Peter are 

a Proc. Iowa A cad. Sci., vol. 4, 1898, p . 60. 
DETERMINATION AND CORRELATION OF FORMATIONS. 97 

Stones River rocks, either resting directly upon the sandstone or separated from · 

it by a thin clayey bed that may very well be the equivalent of the fJoachim. So 

far, then, as stratigraphic position is concerned, it will be seen that the limit of 

uncertainty respecting the exact equivalence of the two sandstones is extremely 

narrow. 

Lithologically, there is absolutely no constant difference between the St. 41 

Peter and Crystal City sandstones. Both consist almost .entirely of loosely 

cemented rounded grains of translucent quartz, and practically every feature of 

the one may be duplicated in the other. Except where it can be shown to have 

been reworked or otherwise ehanged by subaerial agencies prior to its resubmergence in subsequent Paleozoic times, the Key sandstone is in all essential 

respects lithologically identical with the Crystal City and St. Peter sandstones. 

Admitting the inclusion of the Shakopee horizon in the Yell ville limestone the 

only reason that may be urged against a positive correlation of the three sandstones is the absence in northern Arkansas of the First Magnesian or Joachim 

limestone and Stones River rocks which overlie and ·limit the Crystal City sandstone. in Missouri and the St. Peter sandstone farther north. Because of the 

nature of the deposits, it is extremely unlikely that fossils can ever be found to 

establish the identity of the Key sandstone and the two other sandstones with 

which every available line of evidence unites it. Neither is it likely that their 

identity can be established by tracing the formation, either above or under 

ground, from exposures of Crystal City sandstone to those of the Key sandstone, 

since both sandstones have been removed by pre-Carboniferous erosion over a 

large part of the area intervening _between their typical exposures. On the 

other hand, however, it is even more difficult to prove that the Key sandstone is not 

strictly an extension of the Crystal City ,and St. Peter sandstones. Indeed, not 

a single argument presents itself that is not negatived by facts mentioned m 

support of the writer's contention that the three sandstones all represent one 

and the same geologic formation. 

Izard lime~ton .-No fossils that could be specifically identified were obtained 

from this limestone in Arkansas, but in its lithologic characters and stratigraphic 

position it corresponds so well with the upper part of the Viola limestone of the 

Arbuckle and Wichita Mountains of Indian Territory and Oklahoma, that paleontologic evidence is scarcely necessary to fix its horizon in stratigraphic classification. What is regarded as the equivalent of the Izard in the Viola limestone 

is also extremely unfossiliferous in the Arbuckle Mountains. . But it is there, 

the same as in northern Arkansas, followed by that member of the Richmond 

group to which Branner has applied the name Polk Bayou limestone. The lower · 

and middle parts of the Viola limestone, on the other hand, afford a number of 

4538--~o. 24--04----7 

'· 
. 98 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

species of fossils indicating an age extending from early Trenton to and perhaps 

through Utica and possibly Eden (?=Frankfort). 

Polk Bayou linu stone.-'Vith a list of fbssib like the following there can be 

no doubt concerning the exact age of this limestone: 

Fossils of Polk Bayo_u limestone . 

• Leioclema wilmingtonense Ulrich. 

Monotrypella quadrata Rominger. 

Dalmanella jugosa James. 

Dalmanella macrior Sardeson. 

Platystrophia acutilirata Conrad. 

Plectorthis kankakensis MQChesney. 

Dinorthis proavita Winchell and Schuchert. 

Ra:finesquina kingi Whitfield. 

Rhynchotrema capax Conrad. 

B~ad-like joints, one quarter inch thick, of the 

column of an undescribed crinoid-highly 

characteristic of the horizon. 

All of the above fossils are characteristic of the Richmond and most of them 

of that phase of the group that is developed chiefly west of the eighty-seventh 

meridian. The Fern vale formation of Middle Tennessee ct represents practically 

the same horizon. 

The Polk Bayou limestone and the following Silurian and Devonian formations occur only at irregular intervals around the southern border of the Ozark 

uplift. This irregular distribution evidently is due almost entirely to the fact 

that the portions now' expo~ed were laid down in generally narrow troughs or 

embayments of the Ozark shore line. Beginning with the Polk Bayou sea, these 

bays were successively occupied by the St. Clair and Sylamore seas, but as a 

rule it appears that the axes of the troughs gradually moved westward, causing 

the western edges of the embayment formations to advance and the eastern edges 

to retreat geographically. The deposition of these formations in ernbayments of 

a shore line is indicated, the same as those recently described and mapped in 

middle Tennessee by · Hayes and Ulrich, a by the fact that the highest- strata, 

where· erosion has not removed them, reach farthest. Occasionally, also, especially in the case of the Sylamore formation, the deposits are sometimes conglomeratic and generally coarser along their b_orders than in their more central parts. 

SILURIAN FORMATIONS. -

St. Ola1:r limestone.-Prof. H. S. Williams has published long . lists of fossils 

from this formation. b . Many of the species cited by him do not occur in the 

material seeured by the writer, and these absent species are more especially those 

that are to be considered indicative of the Niagara age. This may be explained 

by assuming that there is a higher Silurian horizon near Batesville than those 

aDescription of Columbia quadrangle: Geologic Atlas U. S., folio 95, U. S. Geol. Survey, 1903. 

b Ann. Rept. Arkansas Geol. Survey for 1892, vol. 5, 1900, pp. 286-,.289. 
U. S. GEOLOGICA L SURVEY PROFESSIONAL PAPER NO. 24 PL. XXVI 

A .. OPEN CUT, HULSENBECK PRO PERTY. 

R . FISSURE AND SHAFT HO USE AT BAKER AND M cGRATH MINE. 

U. S. GEOLOGICAL SURVEY 

ILLUSTRAT ilG 

I 

I 

PROFESSIONAL PAPER NO. 24 PL. XVI 

GENESIS OF ORES. 
/ 
DETERMINATION AND CORRELATION OF FORMATIONS. 99 

examined by Mr. Adams and the writer. Our collections contain many of the 

species named in his lists, besides a few that are not mentioned by him. The latter 

may have been listed under names that the writer can not accept for them. The 

fauna as known contains a number of species common to the Clinton and Niagara, 

and none, or only a few, that according to our present information are restricted 

to the Niagara. Aside from these possible exceptions most of the described 

species are known to occur in the Clinton of Ohio and in the rocks 9f Indiana, 

Kentucky, Tennessee, and Georgia that have been correlated with the Ohio Clinton 

by Foerste. The same horizon occurs also at the base of the Hunton formation 

in the Arbuckle Mountains of Indian Territory. 

As was first pointed out by Williams, a and later by Van Ingen, b the fauna 

contains two unusual and interesting features. First, the number of European 

Silurian species contained in it that had not been before recognized in America; 

and, second, the diminutive size of many of the species, only a few reaching 'the I 

usual dimensions of the same species in other areas. 

The following list comprises most of 1the characteristic species: 

Fossils of St. Clair limestone. 

Streptelasma calyculus Hall. 

Phrenopora multi:fida (Van Cleve) Hall. 

Dalmanella elegantula Dalman. 

Dinorthis fausta ( Foerste). 

Tri plecia ortoni Meek. 

Mimulus, sp. near waldronensis (Miller). 

Plectam bonites transversalis (Wahl.). 

Strophonella? patenta (Hall). 

Leptrena rhomboidalis (small variety). 

Spirifer radiatus Sowerby. 

Platyostom~ nia.garense Hall. 

Conocardium (three new species). 

Acidaspis obsoleta Van Ingen. 

Proetus corrugatus Van Ingen. 

Calymene vogdesi Foerste. 

Dalmanites arkansanus Van Ingen (near worthned Foerste). 

Sphrerexochus romingeri? Hall. 

Sphrerexochus pisum Foerste. 

Ceraurus, near niagarensis Hall. 

Illrenus; 2 new species near madisonensis Whitfield. 

Lichas nereus Hall. 

_-\.rges arkansanus Van Ingen. 

Arges phlyctenoides (Green) Van Ingen. 

The St. Clair limestone has been observed only in association with the Polk 

Bayou limestone, from which it is sometimes separated by a variable but never 

heavy bed of shale, to which Prof. H. S. Williams has applied the name Cason 

shale. Along the shon~s of the Ozark island both the Cason and the St. Clair \ 

seem to be confined entirely to the troughs formerly occupied by the late Richmond sea, and are even more restricted in lateral extent than the Polk Bayou 

limestone that resulted from the former occupation. The writer has seen no 

evidence of erosion at the top of the St. Clair limestone (as restricted), but some 

effects of that kind might be expected, as a result of the elevation of the area,. 

a Am. Jour. Sci., 3d ser, vol. 48, 1894, pp. 325---331, and Ann. Rept. Arkansas Geol. Survey for 1892, vol. 5, 1900, p. 288. 

b Siluric fauna near Batesville, Arkansas: School of Mines Quarterly, vol. 22, 1901, p. 327, and vol. 23, 1901, p. 34. 
100 ZINC .AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

which lasted through the remainder of Silurian and the greater part of Devonian 

time. Erosion effects on the underlying Polk . Bayou were observed only along 

the edges of the bays where the Devonian· Sylamore formation rests on it. 

Coupling this fact with the other-that the geographic distribution of the St. 

Clair formation is even more restricted than the Polk Bayou-it may be justly 

argued that the later formation occurred only in the bottoms of the troughs, 

which position naturally would protect it against erosion agencies. On the other 

hand, and in accord with observed facts, erosion . would have had free play on 

the elevated borders of the troughs. 

Concerning the underlying Cason shale, its position leads one to suspect that 

it is equivalent to the Sylvan shale of the section in the Arbuckle Mountains, in 

Indian Te~Titory, and to a similar thin and local shale that overlies the Polk 

Bayou-Richmond horizon in sections · along Mississippi River between Kimmswick and Sulphur Springs, Mo. Again, it is possible that all three of these 

shales are to be correlated with part or all of the Thebes sandstone and shales, 

which occupy the interval between the Richmond horizon and fauna mentioned 

and the Girardeau limestone, in the vicinity of Cape Girardeau, Mo., and Thebes, Ill. . . . 

Under proper conditions the Cason shale may prove to be phosphatic. An outcrop of this shale near Duff contained numerous dark pebbles that certainlS: looked 

very much like others that were tested and found to be highly phosphatic. As is 

pow well known, most of the late Ordovician, as well as the Devonian formations, 

on the western shore of the Nashville island contain local deposits more or less rich 

in calcium phosphate. As the conditions about the western and southern shores of 

the Ozark island during at least a part o_f the time were not unlike those that prevailed in Tennessee, similar, though perhaps less extensive and poorer, deposits of 

this mineral may be expected in Arkansas. 

DEVONIAN FORMATIONS. 

Sy7amorre forrmation.-Aside from a small Ling11,la that may be the same as 

L. spatulata of the Genesee shale of New York, and so~e conodonts, this formation 

has afforded no invertebrate fossils. Both the Lingula and the conodonts, 

however, may be classed anrong the characteristic upper Devonian fos.sils, while 

' it is certain that the same forms are found in the Chattanooga shale of Middle 

Tennessee. The only _ other fossil seen from this horizon in Arkansas is an 

imperfect fish bone, about 5 inches long, 2 inches wide, and possibly one-half inch 

thick, that may be one of the mandibles of a species of Dinichthys. The specimen 

is embedded in sandstone. Bones of apparently the same fish occur in the Swan 

Creek ph'Jsphate bed of the Chattanooga shale in Tennessee. 

This formation consists of phosphatic sandstone and conglomerate, and dark; 
DETERMINATION AND CORRELATION OF FORMATIONS. . 101 

often fissile, shale. The sandstone i~ composed chiefly of rounded grains of quartz, 

evidently derived from neighboring areas exposing the Key sandstone, and more or 

less phosphatic matter. The latter is often confined to black, clayey, nodule-like 

pebbles. On the whole the Sylamore formation impresses one aH composed of 

the waste of a · near-by shore, and thus agrees, not only in its faunal and physical 

characters, but also in its origin, with the Chattanooga, formation as developed in 

middle Tennessee. In the latter area the Chattanooga formation represents and 

doubtless is a direct continuation of the overlapping upper part of the Ohio shale 

of Kentucky and Ohio. 

CARBONIFEROUS FORMATIONS. 

LOWER MISSISSIPPIAN FORMATIONS. 

Noel shale and Boone lirrwstone.-The fossils collected from · these horizons 

were turned over to Dr. George H. Girty. The early Mississippian age of this 

interval being pretty well established, lists of fossils from its members are not . 

so essential as from some of the higher Carboniferous horizons. Being familiar 

with the Bryozoa, the writer was able to identify in the field most of the species 

of that class. Among them were three species of the remarkable genus 

Evactinopora, viz, E. grandis Meek and Worthen, E. seoyradiata M. and W., 

and E. quinqueradiata Ulrich. These occurred near the base of the St. Joe 

limestone member, one-half mile west of St. Joe. The only other known 

occurrence of these species is in the vicinity of Burlington, Iowa, where they 

occur in the lower half of the Burlington limestone. Extraordinary forms like 

those of Evactinopora always are comparatively short lived, hence they may with 

much confidence be regarded as holding the same horizon in Arkansas· and Iowa. 

Assuming that this is true, then the underlying Noel shale may, on stratigraphic 

grounds alone, be correlated with the Kinderhook and since the evidence of the 

. few fossils seen from this shale is all in favor of this correlation, there is little 

or no reason for doubt as to its correctness. 

The Noel shale corresponds in position and lithologic character and doubtless 

is equivalent to the shale sometimes found at the ·base of the Tullahoma for.mation 

of middle Tennessee.a The remaining cherty portion of the Tullahoma is equivalent to the Boorie limestone of Missouri and Arkansas and practically 'to the 

Fort Payne chert of Alabama, Georgia, and East Tennessee. 

The cherty limestone of the Boone, which makes up the upper and greater 

part of the formation, was determined in the field, on fossil and stratigraphic evidence, to be of Keokuk age. Beneath this portion of the formation and separating it from the typical, often pink, St. .Joe limestone member, is, at least 

a Description of the Columbia quadrangle: Geologic Atlas U. S., folio 95, U. S. Geol. Survey, 1903. 
, 

102 ZINC .AND LEAD DEPOSITS OF NORTHERN .ARKANSAS. 

locally, a sparsely cherty, subcrystalline white or gray limestone, generally containing 8pir·1'j'er logani in abundance, that would be more appropriately referred 

to the St. Joe limestone member than to the overlying member. If this .a'rrangement were adopted the divisions of the Boone formation would correspond essentially, if not exactly, with the Burlington and Keokuk divisions of Williams's 

Osage group in the Mississippi Valley north of St. Louis. This white or gray 

limestone probably is included with the beds to which Williamsa has applied the 

name ,of Carrollton limestone, but as the section at Carrollton, Mo., seems to contain also the lower part of the more highly cherty upper member, the adoption 

of the name, except with a modified meaning, would not secure the desired discrimination between the Burling-ton , and Keokuk horizons in the Boone limestone. 

UPPER MISSISSIPPIAN FORMATIONS. 

On account of imperfect stratigraphic comparisons. and erroneous correlations 

the Arkansas geologists caused considerable confusion in the nomenclature of the 

formations above the Boone chert. Probably the most noteworthy of the results 

of the Survey's recent stratigraphic work in . northern Arkansas is the correction 

of current errors and the determination of the true sequ~nce of the Carboniferous formations and their equivalents in ~he much better known section along 

Mississippi River. 

J£oorejield shale (Fayetteville sl~ale, in part, of Branner).-No fossils were 

found in this formation, but as the exposures examined were not favorable to 

their preservation, and, moreover, since no determined effort was made to 

secure organic remains, the formation may not be entirely barren. 

A few miles northwest of Batesville there i, a local deposit of highly fossiliferous limestone and limy shale. which Prof. H. S. Williams has called the 

Spring Creek limestone. Apparently this calcareous formation rests on the 

Boone formation and underlies the typical Moorefield shale. If this is its true 

position it must represent a part of the hiatus that usually occurs between these 

two formations. As the outcrop of the Spring Creek limestone · corresponds 

. geographically with the trough near Batesville containing the Polk Bayou and 

St. Clair limestones, it seemR likely that this trough was submerged prior to the · 

wider · submergence that re~mlted in the deposition of the Moorefield shale. It 

is to be regretted that at the only known locality for the Spring Creek limestone 

its relations to overlying beds are obscured by a small . fault. Still, there is little 

room for doubt that this formation underlies the Moorefield shale, whil~ the 

increase of argillaceous matter toward the top of the exposure probably indicates 

that the calcareous beds grade upward into the shale. Though of small consea Ann. Rept. Arkansas Geol. Survey for 1892, vol. 5, 1900, p. 334. 
DETERMINATION AND CORRELATION OF FORMATIONS. 103 

quence areally, this calcareous formation is too important geologically to be 

entirely neglected in the classification of the Mississippian rocks of Arkans.as. 

Perhaps it is sufficiently accounted for by ranking it as a member of the Moorefield formation. 

The age of the Spring Creek limestone is determined less by its own fossils 

than by its stratigraphic position and the faunas of the formations above and 

beneath it. If the overlying Batesville formation is~ as the writer believes, early 

Chester in age (Ste. Genevi~ve and Cypress) and the upper part of t~1e Boone of 

Keokuk age, then the Spring Creek limestone member must fall in between 

the two. Several points might be discussed in the effort to narrow the choice, 

but it must suffice for the present to state that the most probable date of its 

deposition is the St. Louis age. In estim~ting this opinion it is to be remembered that the writer considers the St. Louis as a distinct formation overlying 

the Spergen Hill formation, and both of them as overlying the Warsaw. 

Mr. Stuart vVeller, who gathered most of the material from this limestone 

reported on by Professor Williams, a evidently secured more material and species than the writer, whose collections, however, include all the strange species 

that give the fauna so peculiar an aspect when compared with more eastern 

faunas of similar age. Particrilarly notable among these are three brachiopods, 

one a Lei~rhynchtts, probably correctly identified by 'Yilliams as L. papyraceous 

Meek; the second, Rhynclwnella eurekensis Walcott, and the third, a Spirifer, more 

closely related to the European S. bisulcatus Sowerby than to any American 

species. The first two of these species occur in Nevada in beds variously identified as Devonian or Carboniferous, though now almost certainly to be referred 

to the latter. 

As to the associated species, of which \Villiams lists abqut 35, b there are 

none, unless the form identified with Ambocmlia jJlanoconvexa (Shumard) may be so 

con~idered, seriously opposing 'an assignment of the bed to the St. Louis age. 

On the other hand, Eumetria marcyi (Shumard), the f>roducti of the types of 

P. cestriensis and P. cora, and most of the specifically identified Pelecypoda and 

Gasetropoda clearly prove that the bed is not older than vVarsaw. Considering, 

further, that the overlying Batesville formation is certainly. not younger than 

early Chester, and that it most probably represents the Ste. Genevieve limestone 

and the Cypress sandstone of that group, the correlation by Williams and Weller 

of the Spring Creek limestone with the Warsaw, St. Louis, or Spergen Hill 

formations seems. well sustained. 

Williams c publishes lists of fossils from three other. localities that he refers 

a Ann. Rept. Arkansas Geol. Survey for 1892, vol. 5, 1900. bibid., p. 343. cibid., pp. 353 and 354. 
104 ZINC AND LRAD DEPOSITS OF NORTHERN ARKANSAS. 

to the horizon of the Spring Creek limestone, namely, Mountain View, Carrollton, 

and St. Joe. In the writer's opinion these faunas belong to the upper shale of 

the Fayetteville formation, that is, to the interval lying between the sandstone 

member or lens of that forination and the "'Archimedes" or Pitkin limestone. This 

horizon is well exposed and more than commonly fossiliferous at Marshall. 

At its top the Moorefield shale includes arenaceous layere, and thus passes rather 

gradually into the Batesville sandstone. There seems to have been no break in 

deposition between the ~1oorefield shale and the Batesville sandstone, but instead 

a change in kind of material deposited. This change may be readily explained as 

due to the greater area that was being eroded by the extending river systems 

and by change8 in direction, or the inauguration of new currents, during the 

growth of the sea. Tracing the shale northward from Moorefield near Batesville, 

where it seems to have reached its greatest development, it gradually thins out 

on the southern flanks of the Ozark Island, finally allowing the Batesville sandstone to overlap and rest on the Boone chert. In the southern half of the Yellville quadrangle it is probably wanting as a rule, while its maximum thickness 

here does not excee~ 10 feet. At Marshall, where Branner mapped the shale as 

Fayetteville, and a few miles southeast of St. Joe, the lower part includes a layer 

of oolitic limestone. That the shale at these localities js not the Fayetteville 

becomes evident from the facts brought out in the following discussion of the 

fauna of the Batesville sandstone. 

Batesville sandstone (Batesville sandstone of .Branner, not Simonds; Wyman 

sand8tone of Simonds).-The fauna of this horizon has been made the subject of 

a special paper by Mr. Stuart Weller. a In this paper he describes 30 species of 

fossils collected at the typical exposures of the formation near Batesville. Thirteen of this numb~r are regarded as new. As a result of his study he correlates 

the Batesville sandstone with the Aux Vases sandstone of Illinois and the Maxville limestone of Ohio. 

A special effort was rp.ade to secure a good representation of the fauna of this 

sandstone. Two of Mr. Weller's localities near Batesville were visited, 31 species 

being secured at one and 26 species at the other. The writer succeeded in 

obtaining the same number of species as Mr. "Teller, but not the same forms, 

about . one-third of the species collected not . being in common. Three other 

exposures were searched with better success, one at Marshall and two in the 

vicinity of St. Joe. The Marshall locality afforded 39 species. Only one of the 

St. Joe collections-that from rocks thrown out in digging a well in the villagewas studied, the number. of species amounting to 53. The other lot, secured from 

the basal beds, contained some unusually good material, but was lost in transit. 

a Trans. New York Acad. Sci., vol. 16, 1897, p. 281. 
DETERMINATION AND CORRELATION OF· FORMATIONS. 105 \ 

Excluding the "fucoids,"_ the total number of distinct species making up 

the list from these four localities is 98. Of this num her, 41 species occur also 

in the sandstone lens or member of the overlying Fayetteville shale, _ and these 

should be deducted if the comparisons between the typical Batesville and the 

'• v\T yman" sandstone of the other localities are to be entirely trustworthy. This 

leaves 57 species to be considered. In judging of the result of the comparison 

it should be borne in mind that the Batesville collections were derived from the 

lower part of the sandstone, those from Marshall represent an horizon nearer 

the middle, while those studied from St. Joe come from the upper 10 feet. 

Of 47 species from the two Batesville localities, which will be treated as. 

one, 19 are found beyond the middle of the Fayetteville shale. Deducting these, 

leaves 28 characteristic Batesville sandstone species. Twelve of these occur also 

at either Marshall or St. Joe, or at both, with 8 at the former and 7 at the -

latter locality. Including most of the species of long range, 29 out of 47 Batesville species have been found also in the "Wyman sandstone" at Marshall and 

St. Joe. Either proportion, H- or !-h representing species common to Batesville 

on the one hand and Marshall and St. Joe on the other, is more than sufficient 

to establish the equivalence of the rocks under consideration. The value of the 

evidence upon which this conclusion is based is considerably enhanced by the 

fact already mentioned that the BateRville collections come from the lower part 

of the sandstone and that the St. Joe locality, whose fossils were studied, represent 

the top. 

According to the collections made by Mr. Adams and the writer, 16 species 

out of a total of 4 7 are known only from Batesville, while 19 pass into the 

Fayetteville formation; 14 species out of a total of 39 are known only fron1 

Marshall, while 13 occur also in the Fayetteville; and 16 species out of a total of 

53 occu,r only at St. Joe, while 28 of the number pass upward into the Fayetteville. As might be expected, the proportion of species p~ssing upward into the 

Fayetteville formation to the total number is greater in the upper part than in 

the lower. 

The upper part of the formation in the vicinity of St. Joe contains a number 

of interesting fucoids, among them a large I-Ielmintlwida and a good species of 

Scalarituba, a genus recently proposed by Weller. a The same horizon and fossils 

were observed at Batesville also, holding about the same stratigraphic position. 

Weller's correlation of the Batesville sandstone with the Aux Vases sandstone 

o{ Illinois and Missouri is ~' ery close. He seems, however, not to have been 

acquainted with the fauna of the Ste. Genevieve limestone that intervenes, in 

western Kentucky, southeastern Missouri, and southern Illinois, between the 

a Weller, Stuart, Kinderhook faunal stuqies, No. 1: Trans. St. Louis Acad. Sci., vol. 9, 1899, p. 12. 
106 ZINC AND LE.AD DEPOSITS OF NORTHE]{N ARKANSAS. 

Cypress sandstone ( =Aux Vases sandstone)' and the St. Louis limestone. This 

fauna contains many species suggesting the Chester, but almost equally as many 

relating it. to the St. Louis. It occupies just the position suggested by the mixed 

St. Louis-Chester fauna of the Batesville sandstone. Indeed, a comparison of 

the Ste. Genevieve and Batesville faunas reveals a considerable number of species 

common to both. It is to be regretted that many of these are new to science 

and, further, that the fauna of the Ste. Genevieve limestone has not yet been 

published. Under the circumstances, therefore, it would be of little value to add 

a list of species to this discussion. 

The Batesville sandstone having been considered by the geologists of the 

Arkansas survey as overlying the Fayetteville shale, it followed very naturally 

that when they found a sandstone beneath the shale it had to be considered as 

distinct from the Batesville. Hence, the ''Wyman sandstone" became a necessity. 

The same error concerning the stratigraphic relations of the two formations 

caused them to propose another name for the shale above the Batesville sandstone 

at Marshall. Now that it has been sh~wn that the Batesville sandstone really 

underlies instead of overlies the Fayettevil1e shale, and that the stratigraphic 

succession is essentially the same about Fayetteville and Marshall, the two names 

Wyman sandstone and Marshall shale naturally fall into the synonymy, respectively, of the previously named Batesville sandstone and Fayetteville shale. In 

consequence of these corrections of nomenclature the shale beneath the Batesville 

sandstone was left without a name. Being a mai'f>able lithologic unit south of the 

Yell ville quadrangle, Mr. Adams proposes to call it the Moorefield shale. 

At the typical locality the Batesville sandstone attains considerably greater 

thickness than has been observed elsewhere. Here its base is also somewhat 

shaly, but the shale is decidedly arenaceous until the section descends into the 

top of the underlying Moorefield shale. The rest of the formation, comprising 

much the greater part, is composed of nearly pure sandstone. In the more 

northern exposures, especially those located within the Yellville quadrangle, the 

fresh saqdstone is strongly calcareous, some of the beds being more properly 

called arenaceous limestones. As it is to be expected from this change in lithologic character the volume of the formation decreases northwardly, the beds 

becoming at the same time also more diversely fossiliferous with the increase of 

their calcareous constituent. 

Fayetteville shale (Fayetteville shctle of Simonds and Branner and Marshall 

shale of Branner).-Until reJently this formation has been considered as '"almost 

if not completely bar'ren of fossils." As a rule this appears true, but the shale 

contains calcareous and arenaceous bands and lenses that are simply crowded 

with organic remains. A large proportion of these also is excellently preserved. 
DETERMINATION .AND CORRELATION OF FORMATIONS. 107 

The lower half of the formation has for several years been known to contain 

calcareous .lenses or concretions holding a considerable number of Cephalopoda 

and Pelecypoda, whil~ the upper part, exposed in the railroad cut at Fayetteville, has afforded a Batostomella, a few Brachiopoda, and several mollusks. 

In the course of the writer's investigations a bed of sandstone, more or less 

highly calcareous when fresh, was discovered, first in the vicinity of St. Joe and 

later at Fayetteville. The fossiliferous portion of this bed has a maximum thickness of less than 10 feet. The result of the study of the fossils _ from this bed 

is a list comprising 42 species from the first locality and no less than 92 from 

the second. Thirty of the 42 species collected near St. Joe occurred also in the 

Fayetteville collection. Adding the remaining 12 to_ the 92 ·found at Fayetteville 

we have a. total of 104 species. 

Many. of these specie::; are new to science and the majority of these again 

are not known out of Arkansas. A large number, however, of both old and 

new species are recognized as forms marking the lower half of the Kaskaskia 

limestone division (i. e., the middle part) of the Chester group of shales, sandst<;>nes, and limestones in Illinois ·and Kentucky. The writer, theref~re, is satisfied 

that the Fayetteville formation represents that portion of the Cheste~ age. _ This 

opinion is_ confirmed by the overlying Pitkin limestone, which he is equally confident represents an upper part of the Chester group of the Mississippi · Valley. 

So far as observed by the wr.ter, the fauna of the Pitkin agrees better with that 

of the upper limestone of the proposed Birdsville formation of the Chester than 

with any of the other divisions. 

In arriving at these conclusions chief reliance is placed upon certain unde-

. scribed Pelecypoda and species of Bryozoa, like Archimedes compactus Ulrich, 

A. communis Ulrich, and A. swallovanus Hall, which occur in the Fayetteville 

fauna, and in Kentucky and Illinoi.::; are restricted to the basal part of the Birdsville and to the underlying Tribune limestone. 

The ~layetteville formation consists of an upper and a lower shale member, 

with a sandstone len~· or wedge between them. The middle member, which may 

represent the W edington sandstone of this report, appears not to have been 

observed or recognized before at Fayetteville, the typical locality, but it outcrops 

there at several points, notably at the north end of the railroad cut, and, better, 

100 'yards . or so farther north in a gully on the west side of the track. At both 

of these points the bed is very calcareou:5, but weathers into a rusty porous 

sandstone, crowded with Chester 'fossils. It is only about 4 or 5 feet thick here, 

and possibly disappears entirely or occurs only as oecasional lenses farther 

- west. At Pilot .. Mountain, 2 or 3 miles east of St. -Joe, however, it consists of 

thin, even-bedded fi~e-grained sandstones at the top, and la;Yers. of similar sand-
108 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

stones alternating with arenaceous shales below, the whole aggregating a thickness of 60 feet or more. It is very improbable that the whole of these 60 feet 

are equivalent to the bed at Fayetteville. More likely the . lower half represents 

an arenaceous phase of the upper part of the lower shale oi the more western 

locality, leaving the upper half, which contains the same fossils, as the representative of the calcareous sandstone member of the Fayetteville , section. The 

upper shale apparently decreases in volume eastward from Fayetteville, being 

either wanting or only a few feet thick in the vicinity of St. Joe and Pilot 

Mountain. At Marshall, however, this member is as thick as at Fayetteville. 

Wedington sandstone (Batesville sandstone of Simonds).-Tbe writer bad no 

opportunity to study this formation in the typical locality, and as no fossils 

were secured there by other members of the Survey, it is impossible to say now 

whether there is a fauna from this horizon or not. According to the evidence 

now available, the Wedington sandstone is a wedge, thickening westward and 

possibly eastward, lying on Fayetteville shale. But whether these underlying 

shales are of the upper or of the lower bed of the Fayetteville formation-an 

important point-is not known. a If the upper bed is really not present in any 

of the sections containing the W edington sandstone, then this sandstone must 

be a later formation, probably overlapping northwardly and westwardly during 

the tim·e there represented by the unconformity between the Fayetteville and 

Pitkin. This unconformity was definitely recognized in several sections near St. 

Joe, where the upper bed of the Fayetteville shales is reduced to a thickness 

of. 15 feet or less, even before the much greater thicknesses of t.he upper bed in 

the sections at Marshall and Fayetteville .had been examined. vVith an unconformity indicating land conditions to the north of these overlapping formations, 

it is quite possible that farther south, where the deeper part of the Fayetteville 

basin occurs, deposition continued through a part or all of the time. This 

deposit would be the Wedington, and it is according to this interpretation Jlat 

it has been mapped by Mr. Adams. 

On the other hand, if the land conditions so clearly indicated in the sections 

about St. ,Joe were more widely extended than is demanded by the view just 

advanced, then the "'T edington sandstone requires a different explanation. A 

plausible view in that case would be that the W edington sandstone is an 

extension and expansion of the fossiliferous sandstone member above described 

as dividing· the Fayetteville formation into three parts, viz, a lower and an 

upper bed of shales and an intermediate bed of sandstone varying in thickness, 

so far as observed by the writer, from 3 to 60 feet. If the latter view is the 

a An intermittent bed of shale, identified as Marshall shale, is shown in columnar sections published by 

Simonds in his report on Washington County, Ark. As this shale overlies the Wedington sandstone, which he calls 

Batesville sandstone, the writer regards it as highly probable that it is the partially eroded remnant of the upper 

member of the !"ayetteville. 
DETERMINATION AND CORRELATION OF FORMATIONS. 109 

correct one, then the W edington sandstone should be considered as a member 

of ·the Fayetteville formation rather than as a distinct formation. Otherwise it 

would ge necessary to give a new name to either the upper or the lower bed of 

shale, and that would produce undesirable re ults~ Thus, if the name Fayette-

':'ille should be retained for the upper member, then it would stand only for 

the lesser and more unequally distributed part of the shale. formation for which 

the name was proposed originally. On the other hand, if the lower b~d should 

be selected as the more appropriate, the excellent exposure in the railroad cut 

at Fa.yetteville could no longer be referred to as an example of Fayetteville shale 

because it would then belong to the newly defined formation. 

Though the writer has no intention of taking a definite stand in the matter, 

it yet seems desirable to state that he prefers the second of the two perhaps 

equally plausible interpretations above suggested. 

Pitkin li?Twstone.-The fauna of the . Pitkin limestone, heretofore denominated 

Archimedes limestone, is undeniably of Chester age and, indeed, has been so 

considered by all writers. However, the recognition of the ·Pottsville or early 

Pennsylvanian age of the overlying members of the Morrow formation, necessitates some modification of views held heretofore. In consequence of the transfer 

of the Brentwood or "Pentremital" limestone, one of the members of the JVlorrow 

formation, which also had been commonly regarded _ as of Chester age, from the 

Mississippian to the _ Pennsylvanian series, it is obvious that the Pitkin limestone 

may now take a higher position in the geologic seale than was assigned to it before. 

As has been stated on a preceding page, the fauna of the Pitkin (Archimedes) limestone fully warrants placing the formation well up toward the close of the Che~ter. 

The unconformable contact with the unJ.erlying Fayetteville also tends to place 

this limestone high in the Chester group. Under the circumstances, it seems 

to the writer that the Pitkin limestone can not be considered older than the 

upper part of the Birdsville· formation, which is the uppermost of the four 

divisions into which the Chester group is divided in western Kentucky. Indeed, 

\ 

it is believed that the Pitkin includes beds at the top that are of even later date 

than any Chester strata remaining in the Mississippi Valley sections of that group, 

since the top of the Chester was there subjected to erosion through a longer period 

of time than it was in Arkansas. 

EARLY PENNSYLVANIAN FORMATIONS • 

.Morrow formation.-Counting from the base upward, this formation includes 

the Washington shale and sandstone, the Brentwood (Pentremital) limestone, the 

Coal-bearing shale, the Kessler limestone, and an unnamed bed of shales and 
110 ZINC AND LEAD DEPOSITS OF NORTHERN ARKANSAS. 

sandstones of the geologists of the Arkansas survey. Until recently these beds, 

excepting the uppermost, were included, together with the underlying Pitkin 

(Archim~des) limestone and Marshall Rhale, in the Boston group of Branner, and 

placed at the top of the Mississippian series. The two latter formations, as the 

writer has endeavored to show, are certainly not older than the upper or Kaskaskia 

limestone division of the Chester group, which includes the latest deposits o£ 

the Mississippian series in the basins east of the Ozark uplift. 

The Morrow formation therefore must represent a later time interval than 

the Chester as developed in 'the Mississippi and Ohio valleys. That it is not to 

be viewed as an upward extension of the Mississippian series is demonstrated (1) 

by the existence in Arkansas of a. well-marked unconformity at the top of the 

Pitkin, which horizon corresponds with the wide spread unconformity at the top 

of the Chester in the Ohio Basin, and (2) by the Pennsylvanian aspect of the 

marine faunas of the Morrow. On seeing the stratigraphic relations of the 

various · members of the formation to each other, and more particularly to 

the underlying Pitkin, the writer at once came to the conclusion that they are 

younger deposits than any Mississippian formations known to him. Nor have 

the fossils from the limestones, seen then and si_nce, caused ail.y modification of 

the view expressed in the field. The only questions now remaining unanswered 

are: What are the relations of the 1\'Iorrow formation to the Pottsville? Are all 

or only some of its members represented in that great series of shales, sandstones, 

and conglomerates of the Appalachian and more western portions of the Ohioan 

province? 

As is well known, the Pottsville· group . em braces many beds beneath . the 

strongly conglomeratic (Millstone grit) upper member that constitutes the most 

characteristic and, in many areas, the principal or only lithologic :unit of the 

group. All parts of the group, and more particularly the portions beneath the 

main conglomerate, seem to have leveled the earth by filling the great hollows 

that had resulted from the emergence at the close of the Chester, and the severe 

orographic movements and subsequent adjustments that followed close the~eafter. 

Naturally the group affords everywhere the clearest evidence of its overlapping 

character, the earliest deposits occurring only in the deepest troughs, while those 

of subsequent dates spread wider and wider over the sloping flanks 'of the anticlinal ridges and domes. 

As a rule, marine faunas are wanting in Pottsville deposits east of the 

Mississippi, and so far none has been described in that region. This is due 

probably almost solely to the turbid condition of the water, which rendered it 

unfavorable to the invasion and development of animal life. Even t~e few hardy 
DETERMINATION AND CORRELATION OF :FORMATIONS. Ill 

species tha,t may have ventured or possibly were driven in, had but a small 

chance of, living in the disturbed waters. 

But were there no areas on the continent in which marine faunas continued to · I • 

exist through at least the earlier parts of the Pottsville epoch? The writer has 

satisfied himself that there were, and that, we ~ave in the limestones of the Morrow 

formation tbe remains of periodic invasions of such faunas; and further that these 

earliest Pennsylvanian. faunas existed perhaps without interruption in basins to 

the southwest of northern Arkansas. But the last phase of the pro'blem can not 

be discussed here except to barely indicate the source of the evidence upon which 

the writer's view is based. This is in the Bend limestone and shale of central 

Texas, which is, as maintained by Cummins, of Pennsylvanian ~ge and not Mississippian. This Texan fo~·mation, it is believed, affords perhaps the most complete or rather the least imperfect record of these as yet little known early 

Pottsville faunas that we are likely to find. I 

The occurrence of Pentremites ip the fauna of the limestones (Brentwood 

and Kessler) of the Morrow formation a imparts a more ancient aspect to it than, 

according to present knowledge, looks right in a Pennsylvania fauna. This occurrence, however, seems due to local conditions. Pentrernite..'t, as is well known, do 

not occur in the Far West in rocks correlating with late Mississippian deposits. b 

In the limestones and shales of the Chester group, however, species of this genus 

are extremely abundant-indeed, the genus attained the acme of its development, 

both in species and individuals, at this time and in the areas embraced by the 

Ohioan province. The stock was still vigorous when the almost general emergence of the Ohioan provinee at the close of the Chester partly exterminated it 

and forced its remnants southwestward into the :Mississippian embayment. With 

the resubmergence of the land that inaugurated the Pottsv\}le epoch the survivors 

of the stock returned where and when they could; and is it not quite reasonable 

to expect that the favorable conditions prevailing along the southern shore of 

Ozarkia, as the ancient landmass gathered about the. nucleus of the Ozark uplift 

may be called, would be accepted?· Some of the rest of the Morrow fauna, 

howttver, probably came in from the Far Northwest, where, according to detera Dr. George H. Girty has brought together and proposes in the near future to describe an excellent collection of 

fossils from these limestones. 

bIn a list of fossils published by Meek in 1873 (U. S. Geol. and Geog. Surv. Terr., pp. 468-470) as from "Old Baldy," 

near Virginia City, Mont., two species of Pentremites are identified, one doubtfully, with well-known Chester species. 

The list comprises 38 species, determined generically, and of these less than half are identified specifically. Me.ek 

regarded the fossils as probably indicating late Mississippian, but an analysis of his list casts considerable doubt upon 

this determinatio.n. It contains no less than 8 names of species that are considered good Pennsylvanian fossils. In 

the light of the Morrow fauna, may not at least a part of the section at "Old Baldy" prove to be contemporaneous 

with the Arkansas deposits under qiscussion? 
112 ZINC AND LEAD DEPOSITS . 01:!' NORTHERN ARKANSAS. 

minations by Meek (see note on preceding page), ordinary Pennsylvanian fossils 

seem likewise to occur in association with Pentremites. 

The typic~l section of the Pottsville doubtless contains many beds that, on 

account of the overlapping character of this group of formations, are not represented in other sections~ It . is only the upper or main zone of conglomerates 

that attained a geographic distribution at all comparable to that of the middle 

part of the Pennsylvanian series. It is this conglomeratic zone that is represented in the lower Ohio and Mississippi valleys by the l\1ansfield sandstone of 

the Indiana geologists and in northern Arkansas by the Winslow. We have, then, 

a datum line upon which we may proceed further in the effort to determine the 

stratigraphic equivalents of the Morrow formation in the Appalachian section. 

Mr. David White, whose determinations of Carboniferous fossil plants are 

deserving of the highest confidence, refers the :qi.iddle or "Coal-bearing shales" 

member to the lower or Sewanee stage of the upper · Pottsville. This determination is quite acceptable to the writer, except that he would prefer, because of 

extensive orographic movements following the Sewanee stage, to call it lower 

Pottsville. However, that point has no immediate bearing upon the questions 

here at issue, the important feature of Mr. White's determinations being that it 

leaves a large series of deposits iJ the Appalachian section with which the two 

lower members of the Morrow foi mation may be correlated. 

So far as the writer's limited cdmparisons of the fauna of the Brentwood limestone, which underlies, and the Ke sler limestone, which overlies the Coal-bearing 

shales, have extended, they have appeared alike in all essential respects. There is, 

therefore, no known reason for beli ving that the Pentremital limestone belongs to 

an earlier or different group of rocks than is indicated by the plants in the intervening Coal-bearing shales. Of course, the Morrow sediments beneath these shalP,S 

can not compare in thickness with the beds supposed to correspond in the Appalachian section; but that can have no adverse effect upon the correlation, since 

the relative thickness of clastic formations depends, aside from other obvious 

circumstances, entirely upon local conditions of the land supplying the material; 

and under average circumstances limestones must have taken longer to form than 

sandstones and shales. Besides, there are localities in the Appalachian region, 

notably the one in which the Greenbrier limestone occurs, in which no unconformity has been observed between limestones and calcareous shales holding a 

Chester fauna and a following series of rocks that are classed as Pottsville. It 

would, therefore, appear that in such limited areas or troughs sedimentation may 

have continued without interruption from late Mississippian into early, yet undeniable, Pennsylvanian time. .If this possibility proves to be a fact, then the 
DETERMINATION AND CORRELATION OF FORMATIONS. 113 

Morrow formation, as known to-day, contains no strata quite so old as the earliest 

Pennsylvanian deposits in certain Appalachian regions. Accordingly, providing 

the Pottsville group extends to the base of the Pennsylvanian, the Morrow 

formation must be referred to that group. In the -correlation table on a preceding page the formation has· been so arranged, and the only point connected 

with the writer's estimate of the Pottsville, as given in the table, that may not 

be acceptable to Mr. White and other geologists, is the implied restriction of 

the upper (late) Pottsville to the widely distributed conglomeratic zon(3 and the 

inclusion of the remaining beds in the lower (early) Pottsville. 

4538--~o. 24--04----8 
• 
INDEX. 

Page. 

Adams, George I., field work by....................... 90 

Almy mine, description of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 

view of, plate showing............................. 66 

Amos, Richmond Bluff near, view of, plate showing.. 22 

Arbuckle limestone, equivalent of . . . . . . . . . . . . . . . . . . . . 95 

Archimedes limestone, a name for the Palken limestone ....................................... 27 

correlation of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 

Arkansas, northern, lithologic formations distinguished in................................. 90 

lithologic formations in, correlation of, tableshowing ........................... ,....... .. .... 90 

physiography of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-18 

zinc and lead deposits of, historical sketch of. .... 13-14 

zinc and lead district of, faults in ................. 36-39 

generalized section through . . . . . . . . . . . . . . . . . . . 32 

geologic formations in ................... ...... 18-29 

limits of. .................................. ·..... 14 

map of, showing general geology and principal mines ~nd prospects................... ~4 

mines and prospects in . . . . . . . . . . . . . . . . . . . . . . . . 63-86 

ores and minerals in ....... . ................... 39-46 

physical changes in, history of ................ 29-36 

production of.................................. 15 

prospective development of................... 15 

structure of, origin of. ......................... 33-34 

transportation facilities in .... ..•...... ... ... .. 14-15 

Aux Vases sandstone, correlation of ............ 104, 105, 106 

Bain, H. Foster, cited on origin of the breccia deposits. 87,88 

Bain, H. Foster, and VanHise, C. R., cited on origin of 

ore deposits of the Mississippi Valley .•.... 88-89 

Baird Creek, prospects on. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 

Baker & McGrath mine, description of................ 85 

view of, plate showing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 

Bald Dave mine, description of........................ 79 

Bald Jesse mine, description of........................ 72 

Batesville, Moorefield shale near..... . . . . . . . . . . . . . . . . . 26 

Polk Bayou formation near. . . . . . . . . . . . . . . . . . . . . . . . 22 

Silurian limestones near............. . . . . . . . . . . . . . . 30 

Batesville limestone, age and stratigraphic place of... 103, 

104-106 

Batesville sandstone, character, occurrence, and 

thickness of ................................ 26-27 

correlation of.. . ......... . ......................... 90 

stratigraphic place of. ........................... 108-109 

Batie mine, description of. ............................ 69-70 

Baxter County, mines and prospects in, description of. 78-79 

Bear Creek, developments near........................ 63 

Bear Hill mine, description of......................... 69 

view of, ~late showing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 

Bedded breccias, sulphide deposits in ...... ... , ... :. . . 46 

Ben Harrison mine, description of ............. '....... 67 

Bend limestone, age of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 

Bennett mine, description of................ . . . . . . . . . . 85 

Page. 

Beulah mine, description of . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-73 

view of, plate showing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 

Big Buffalo mine, description of.. . . . . . . . . . . . . . . . . . . . . . 70 

Big Elephant mine, description of..................... 70 

open cut a.t, view of, plate showing . . . . . . . . . . . . . . . 68 

Big Hurricane prospects, description of............... 82 

Big John mine, description of . . . . . . . . . . . . . . . . . . . . . . . . . 79 

Birdsville formation, correlation of . . . . . . . . . . . . . . . . . . . 109 

Blende. See Zinc sulphide. 

Boat Creek mine, description of. ... ................... 76-77 

Boat Mountain, coal prospects at...................... 28 

Bonanza mine, description of. ......................... 77,85 

Boone County, mines and prospects in, description of. 63-66 

Boone formation, character, occurrence and thickness 

of .......................................... 25-26 

fracturing and fissuring in.... ...................... 33 

ore deposits in............... . . . . . . . . . . . . . . . . . . . . . . 29 

BoQp . limestone, character and fossils of. ........... 101-102 

correlation of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 

stratigraphic. place of...................... . . . . . . . . 96 

Boston group, age of. ................................ 109-110 

Boston Mountains, physiographic relations of......... 16 

Winslow formation in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 

Branner, J. C., cited on influence of folds in localizing ore bodies.............................. 35 

cited on origin of zinc and lead deposits .......... 87,88 

Branner, J. C., and Willia.rp.s, H. S., section of Arkansas formation given by, table ........ ·...... 90 

Breccia, dolomite, cemented with pink spar, view of, 

plateshowiug.............................. 34 

silicifie·d., marking St. Joe fault, view of, plate showing........... .. . ...... ...... ... •••......... 34 

Breccias. See Fault breccias; bedded breccias. 

Brecciation, production of, by stress, diagram illustrating......................................... 33 

Brentwood limestone, equivalent of.................. 28 

stratigraphic place of.............................. 109 

Buffalo Fork of White River, mines and prospects I 

on ................................... 75-76, 79, 80 

Burchard, Ernest F., aid by............................ 13 

Burlington escarpment, elevation of . . . . . . . . . . . . . . . . . . 17 

Calamine, Ark., zinc smelter erected at............... 14 

Calan;line, occurrence and character of................ 39 

Calcite, occurrence and character of . . . . . . . . . . . . . . . . . . 41 

Canton mine, description of........................... 83 

Carbonate Nose prospect, description of............... 84 

Carboniferous formations, character and fossils of .. 101-113 

correlation of, table showing...................... 90 

Carboniferous system, formations of . . . . . . . . . . . . . . . . . . 24-29 

Carrollton limestone, correlation of .................. 90,102 

Cason s~ale, correlation of . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 

stratigraphic place of. ............................ 99, 100 

Cave Greek, prospects on.............................. 83 

Cedar Gap mine, description of . . . . . . . . . . . . . . . . . . . . . . . 79 

115· 
116 INDEX. 

Page. 

Cementation, relations of, t-: :: ·, '• weatherirg ........ 35-63 

Cerussite, occurrence and cha: _. of................ 40 

Chalcopyrite, occurrence and c."aracter of. . . . . . . . . . . . 42 

Chert, secondary, association of sulphide deposits 

·with....................................... 45 

occurrence and character of . . . . . . . . . . . . . . . . . . . . . . 41 

Chimn~y Rock mine, description of................... 85 

Christie mine, description of . . . . . . . . . . . . . . . . . . . . . . . . . . 78 

Clabber Creek, mines and prospects on ............... 72-73 

Clear Creek, Yellville formation on ................... 19-20 

Clifty Creek, mines on................................. 85 

Climax mine, description of........................... 73 

fault near.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 

view of, plate showing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 

Coal-bearing shale, correlation of . . . . . . . . . . . . . . . . . . . . . 90 

stratigraphic place of. . . . . . . . . . . . . . . . . . . . . . . . . . . . 109, 112 

Colorado mine, description of......................... 67 

Correlation table, description of ...................•.. 91-93 

Country rock, sulphide ore in . . . . . . . . . . . . . . . . .. . . . . . . . . 46 

Cow Creek, mine on................................... 77 · 

Cowan, Yell ville formation near . . . . . . . . . . . . . . . . . . . . . . 20 

Crooked Creek, mines along.. . . . . . . . . . . . . . . . . . . . . . . . . . 63 

Crooked Creek Valley, view across.................... 16 

Crystal City sandstone, equivalents of. ........•....... 96-97 

Cushman, deep well at................................ 19 

Cypress sandstone, correlation of..... . . . . . . . . . . . . . . . . . 106 

Davis Creek, fault crossing............................ 39 

Davy Cr<;>ckett prospects, description of ............... 81-82 

Deformation in northern Arkansas, history of. ........ 32-33 

Devonian formations, correlation of (and table)...... 90 

fossils of ......................................... 100-101 

Devonian period, erosion intervals in................. 31 

sedimentation during ............. : . .............. 30-31 

Devonian Rystem, formations of. ...................... 22-24 

Dolomite, jointed, view of, plate showing............. 66 

Dolomite breccia, cemented with pink spar, view of 

plate showing............................. 34 

Dolomite spar, occurrence and character of........... 41 

"Dry bone" form of Smithsonite, zinc content of..... 40 

Duff, Sylamore formation near . . . . . . . . . . . . . . . . . . . . . . . . 23 

Dyson mine, description of. ........................... 71-72 

East Pigeon Creek, prospect on.. . . . . . . . . . . . . . . . . . . . . . . 78 

Eden limestone, correlation of ............. , . . . . . . . . . . . 98 

Eldorado mine, description of......................... 72 

Elixir prospect, description of. ........................ 64-65 

Epsomite, occm:rence and character of.. . . . . . . . . . . . . . . 42 

Erosion in northern Arkansas, history of. . . . . . . . . . . . . . 31 

Eureka shale, correlation of. ........................ :. 90 

Excelsior mine, description of......................... 81 

St. Joe, fault' near, view of mass of silicified breccia 

marking................................... 34 

Fault breccias, sulphide deposits in.................... 46 

Faults, date and character of. ...................... 33, 36-39 1 Fayetteville, Batesville sandstone near ...... :......... 26 

Morrow formation near . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 

Pitkin limestone near . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 

Wedington sandstone near ..... ·-............ _.... 27 

Fayetteville shale, age and stratigraphic place of.. 106, 107 

character of .................................. 27,107-108 

correlation of...................................... 90 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106-107 

occurrence and thickness of. . . . . . . . . . . . . . . . . . . . . . . 27 

stratigraphic place of...... . . . . . . . . . . . . . . . . . . . . . . 102-104 

Featherstonhaugh, G. W., reference to ................ 13-14 

Fern vale formation, stratigraphic place of............ 98 

"Fool's gold," a name for pyrite...................... 41 

Fort Payne _chert, correlation of....................... 101 

Frankfort limestone, correlation of................ . . . . 98 

' Fr:i;;co property, description of . . . . . . . . . . . . . . . . . . . . . . . . 66 

Page. 

Gaither Mountain, coal prospects at................... 28 

Galena, occurrence and character of.................. 39 

Gambetta prospect, description of..................... 78 

Gangue minerals, character of . . . . . . . . . . . . . . . . . . . . . . . . 43 

Gasville, bottom land of White River near, view of, 

plate showing..... . . . . . . . . . . . . . . . . . . . . . . . . . 16 

Girty, George H., field work by........................ 13 

fossils identified by................................ 101 

work projected by, on fauna of the Morrow formation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 

Gold Standard mine, description of . . . . . . . . . . . . . . . . . . . 79 

Goslarite, occurrence and character of ......... ~ . . . . . . 42 

Goswick prospect, description of . . . . . . . . . . . . . . . . . . . . . . 84 

Governor Eagle property, description of .............. 68-69 

Greenhaw Hollow, prospects in . . . . . . . . . . . . . . . . . . . . . . . 80-81 

Ground water, circulation of, geologic conditions influencing .................................. 34-35 

Gypsum, occurrence and character of.. . . . . . . . . . . . . . . . 42 

Halls Mountain, escarpment of, view showing.. . . . . . . 16 

Harrison, mines near. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-66 

Hawkeye mine, description of......................... 72 

Hawkeye No.1 prospect, description of................ 78 

Hawkeye No.2 mine, description of................... 79 

Hayes, C. W., letter of transmittal by.................. 11 

Hayes, C. W. and Ulrich, E. 0., cited on conditions 

of deposition of Paleozoic formations in 

Tennessee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 

Hopeful prospect, description of....... . . . . . . . . . . . . . . . . 79 

Hulsenbeck mine, description of . . . . . . . . . . . . . . . . . . . . . . 78 

view of, plate showing............................. . 78 

Hurricane fault, description of........................ 39 

Hydrocerussite, occurrence and character of.......... 40 

Hydrozincite, occurrence and character of............ 40 

Igneous rocks, nearest areas of . . . . . . . . . . . . . . . . . . . . . . . . 30 

lola mine, description of .............................. 66-67 

open cut in barren ground near, view of, plate 

showing................................... 66 

Iron sulphide, occurrence and character of ........... 41-42 

!;lard limestone, character, occurrence, and thickness 

of .................. , ....................... 21-22 

correlation of. .................................. 90,97-98 

"Jack." See Zinc sulphide. 

Jackpot (on Buffalo Fork) mine, description of....... 80 

Jackpot property, description of. ...................... 65-66 

Jimmie Creek, mines near ....................... 69-70, 70-71 

Joachim limestone, stratigraphic place and equivalents of ..................................... 96, 97 

Kessler limestone, correlation of . . . . . . . . . . . . . . . . . . . . . . 90 

equivalent of...................................... 28 

stratigraphic place of.............................. 109 

Key sandstone, character, occurrence, and thickness of. 20-21 

correlation of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 

equivalents of .................................. 94,95-97 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 

ledge of, view of, plate showing................... 24 

stratigraphic place of.............................. 94 

view of, in open cut, Big Elephant mine, plate 

showing................................... 68 

Kingdon Springs, mines at ............................ 70-71 

Lead carbonate, occurrence and character of......... 40 

Lead Hill, ore smelted in vicinity of . . . . . . . . . . . . . . . . . . 14 

Lead ore, discovery of, history of. ..................... 13-14 

Lead sulphiQ.e, occurrence and character of . . . . . . . . . . 39 

Little Rock, igneous rocks at.......................... 30 

Little Sugar Orchard Creek, mines near ............... 68-69 

Lost mine, description of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 

Mcintosh mill, description of . . . . . . . . . . . . . . . . . . . . . . . . . 47 

view of, plate showing........ ......... .. .. . ..... 74 

Magnesian limestones, correlation of...... . . . . . . . . . . . . 90 
( 

\ 

INDEX. 117 

Page. 

Marble City prospect, description of................... 83 

Marion County, mines and prospects in, description of. 66-78 

Mark Hanna mine, description of..................... 79 

Markle Hollow, mine in ............................... 67-68 

Markle mine, description of ........................... 67-68 

hand jigs at, view of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 

Marshall, Batesville sandstone near. . . . . . . . . . . . . . . . . . . 26 

Fayetteville shale near . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 

Marshall shale, age and stratigraphic place of ...... 106, 107 

character of------ ----------------·-···--------- io7-108 

correlation of...................................... 90 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106-107 

Maryhattiana mine, description of.................... 75 

Maumee prospect, description of ...................... 80-81 

Maxville lime!> tone, correlation of . . . . . . . . . . . . . . . . . . . . 104 

Meek, F. B., cited on Carboniferous fossils from Montana . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ill 

Mill Creek. fracture near.......... .. .. .. .. .. .. .. .. .. .. 38 

mines near ........................................ 65-66 

prospects on .... , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 

Mill Creek fault, description of........................ 38 

Mines and prospects, description of ................... 63-86 

Mining and prospecting, suggestions concerning ..... 85-86 

Misf'issippi Valley, ore deposits in, source of. ......... 88-89 

Mississippian formations, character and fossils of. .. 101-109 

correlation of. .............................. . . . . . .. 90 

Mississippian province, definition of (note) . . . . . . . . . . . 91 

Mississippian series, deposition of, conditions of...... 31 

formations of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-28 

Moccasin Creek, mines near.. .. .. .. .. .. .. .. . .. .. .. .. .. 70-71 

Monkey Run, prospects on .......................... ·-- 81 

Moorefield shale, character, occurrence and thickness 

of.......................................... 26 

correlation of...................................... 90 

stratigraphic place of. ........................... 102-104 

Morning Star mine, description of .................... 73-74 

fault at............................................. 37 

main cut at east end · of, view of, plate showing.. 74 

Morning Star mine and mill; views of, plates showing. 72 

Morrow formation, age of .. .. .. .. .. .. .. .. .. .. .. .. .. . 109-113 

character, occurrence, and thickness of........... 28 

correlation of. ................................ 90,109-113 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ill 

Mud Hollow prosp'icts, description of................. 81 

Mundie, a name for pyrite . .. .. . . . . . . . . . . . . . . .. . . . . .. . 41 

Nakomis mine, description of......................... 68 

view of, plate showing ............................ ' 68 

Newton County, mines and prospects in, description 

of . .. .. . . . .. .. . .. .. . . . .. . . . . . . . . . . . .. . . . . .. 82-85 

Noel shale, character and thickness of. . . . . . . . 24-25, 101-102 

correlation of. .............................. 23-24, 90, 101 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101-102 

North Star mine, description of....................... 71 

Northern Star mine,, descr~ption of. ................... 63-64 

Ohioan province, time scale of . . . .. .. . . . . .. . .. .. . . . .. . 90 

Old Granby mine, description of ...................... 83-84 

Olympia mine, description of ......................... 70-71 

Orrtovician formations, character and fossils of. ...... 93-98 

Ordovician period, sedimentation during, conditions 

of . . .. .. . . .. .. . .. .. . . . . . . .. .. .. . . .. .. . . .. .. . 30 

Ordovician rocks, correlation of, table of . .. .. . . . .. . . . 90 

Ordovician system, formations of . . . . . . . . . . . . . . . . . . . . . 18-22 

Ore deposits, grouping of rocks with respect to . . . . . . . 29 

relations of, to synclines........................... 35 

source of, opinions of previous writers in regard 

to .. .. . . .. .. . . . .. .. .. .. . . .. . . .. .. . .. . . . . .. . . . 87-89 

Ores, association of, W'ith quartz druses............... 46 

Page. 

Ores, classification of •......... ' ..................... , ~ 44 

country rock associated with...................... 42 

gangue minerals of. .. .. .. . .. .. . .. . .. . .. . . .. . .. .. .. 43 

genesis of, 1 hand specimens illustrating, plates 

showing ................. 48, 50, 52, 54, 56, 58, 60, 62 

minerals associated with .......................... 41-42 

source of........................................... 43 

Ores, oxidized, occurence and character of. . . . . . . . . . . . 39-41 

processes of deposition of. . .. .. .. .. .. .. .. .. . . .. .. .. 44-45 

Ores, sulphide, association of, with secondary chert.. 45 

in bedded breccias .. .. .. .. .. . .. . . . . .. . .. .. . . .. .. . . 46 

in country rock ............. ,...................... 46 

in fault breccias .. . .. . . . . . .. . .. . . . . .. . .. . .. .. .. .. . . 46 

in fissures .......................... L....... ... . . . .. 46 

occurrence and character of. .. .. .. .. .. . . .. .. .. .. . . 39 

primary deposition of, processes of . . . . . . . . . . . . . . . . 44 

secondary deposition of, processes of . . . . . . . . . . . . . . 45 

value of............................................ 39 

Ores and minerals, discussion of. . . . . . . . . . . . . . . . . . . . . . . 39-46 

Oxidized mes, processes of deposition of . . . . . . . . . . . . . . 44-45 

Ozark plateau, ancient topography of. ................ 17-18 

lowlands in........................................ 17 

physiographic relations of......................... 16 

topographic features of............................ 17 

Ozark region, ore deposits in, source of................ 89 

relations of, to Arkansas Valley and Wichita 

Mountain regions, structure sections showing. . . . . . .. . . . . . .. . . . . .. . . . . . . . . .. . . . . . . . . . . 34 

sketch maps of, showing drainage, physiography, 

• and topography............................ 16 

Paleozoic formations, correlation table of............. 90 

Panther Creek, mines and. prospects on ............... 84-85 

Panther Creek mine, description of ................... 8!-85 

Pennsyl~anian formations, correlation of............. 90 

Pennsylvanian series, formations of. .................. 28-29 

Pentremitallimestone, correlation of.................. 90 

equivalents of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 

stratigraphic place of ............................ 109, 112 

Pilot Mountain, section through·.·.................... 37 

Pilot Mountain fault, description of. .................. 37-38 

section showing .................... ~ . . . . . . . . . . . . . . 37 

Pilot Rock prospect, description of. . ............ . . . . . . 68 

Pink spar. occurrence and character of . . . . . . . . . . . . . . . 41 

Pitkin limestone, age of............................... 109 

character, occurrence, and thickness of. .......... 27-28 

correlation of.................................. 90, 109 

Polk Bayou limestone, character, occurrence, and 

thickness of . . . . . . .. .. .. . . . . . .. . . . .. .. .. . . . 22 

correlation of....................................... 90 

fossils of . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .. . . . . . . . . 98 

stratigraphic place of. ............................. 97,98 

Ponca City prospect, description of.... . . . . . . . . . . . . . . . . 85 

Potosi limestone, equivalent of........................ 95 

Pottsville group, stratigraphic limits of . . . . . . . . . . . . . . . 110 

Prospecting and mining, suggestions relating to ...... 85-86 

Purdue, A. H., aid by.................................. 13 

cited on origin of zinc and lead deposits . . . . . . . . . . 87 

Pyrite, occurrence and character of .... · ............... 41-42 

Quartz, occurrence and character of . . . . . . . . . . . . . . . . . . 41 

Quartz druses, ore associated with . . . . . . . . . . . . . . . . . . . . 46 

Red Cloud mine, description of ....................... 75-76 

view of, plate showing .. .. . . . . .. . . .. . . . . .. . .. .. .. . 76 

Richmond Bluff, view of, plate showing.............. 22 

Ridley limestone, stratigraphic place of............... 96 

Rush, Rush Creek fault near, section across........... 36 

, section near ................................. ~..... 36 

view of........................ . ................... 72 
INDEX. 

Page. 

Rush Creek, mines and prospects on .................. 73-75 

Rush Creek fault, description of....................... 37 

section across.. .. .. .. .. .. . .. .. . . .. . .. .. .. .. . . .. .. .. 36 

Saccharoidal sandstones, correlation of . . . . . . . . . . . . . . . 90 

St. Clair limestone, age and stratigraphic place of ... 98-100 

correlation of...................................... 90 

fossils of . .. .. . .. .. .. .. .. .. . .. .. .. .. .. .. .. .. .. .. .. .. 98-99 

St. Francis Mountains, igneous rocks in ............... 29-30 

St. Joe, Sy lam ore formation near ................ ·.. .. .. 23 

St. Joe fault, description of............ .. .. .. . .. .. .. .. . 38 

silicified breccia marking, view of, plate showing_ 34 

St. Joe fault and monocline, section across ...... _. . . . . 38 

St. Joe limestone, ledge of, view of, plate showing.... :24 

\ stratigraphic place of ................. ·.-......... 101-102 

St. Joe mine. See Excelsior mine. 

St. Joe monocline, description of. ................ ,.... 38 

St. Louis limestone, stratigraphic place of............. 106 

St. Peter sanO.stone, equivalents of .................... 96-97 

Salem upland, character and extent of................ 17 

Sam Hill mine, description of . . . . . . . . . . . . . . . . . . . . . . . . . 77 

Schoolcraft, H. R., reference to explorations by_...... 13 

Searcy County, mines and prospects in, description of. 79-82 

Sedimentation in northern Arkansas, history of. ...... 29-31 

Shaddock Branch, prospects near .................. _ . _ 82-83 

Shakopee limestone, stratigraphic place of. ......... _. 96, 97 

Silicified breccia, marking St. Joe fault, view of....... 34 

Silurian formations, correlation of (and table)........ 90 

fossils of ............. - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98-100 

Silver Hollow mine, description of.................... 76 

Simonds, F. W., cited on Batesville sandstone... ...... 108 

Smithsonite, occurrence and character of ........ ·..... 40 

Spar. See Dolomite spar; Pink spar. 

Spavinaw, Ind. T., igneous rocks at... ...... ........... 30 

Sphalerite, metallic zinc in ........................ _ .. _ 39 

Spier mine, description of. ............................ 82-83 

view of, plate showing ...................... _ .. _.. 82 

Spring Branch, fault line near ...................... __ 37 

Spring Creek limestone, age and position of . ...... . 102-104 

correlation of...................................... 90 

Springfield upland, character and extent of........... 17 

Starlight mine, description of......................... 72 

Stones River limestone, stratigraphic place of ........ 96,97 

Strawberry River, lead mine on, reference to ........ _ 13-14 

Sugar Orchard Creek, mines and prospects near . . . . . . 69 

minesnear ......................................... 63 

Sugarloaf Creek, mines near........................... 68 

Sulphide ores, association of, with ~econdary chert... 45 

occurrence of, in bedded breccias ........... _. _... 46 

in fault breccias............................... 46 

in fissures ................................ ~ . . .. . 46 

in the country rock............................ 46 

primary deposition of, processes of .... ........ _. _. 44 

secondary deposition of............................ 45 

value of............................ . . . . . . . . . . . . . . . . 39 

zinc and lead in, amount of. .. .. .. .. .. .. . .. .. .. .. . 39 

Summit Home mine, description of . . . . . . . . . . . . . . . . . . . 71 

Susquehanna mine,, description of... .................. 69 

view of, plate showing .. .. .. .. .. .. .. . .. .. . . .. .. .. . 68 

Sylamore, Engles Bluff near, view of, plate showing.. 22 

Sylamore formation, age of. .............. : ............ 23-24 

character, occurrence, and thickness of ... 22-24,100-101 

correlation of. ........ ---........ .................. 90 

fossils of .......................... , .............. 100-101 

Sylvan shale, correlation of............................ 100 

Synclines, relations of ore bodies to ... ...... ....... _ . . 35 

Tallow clay, occurrence and character of ............. 40-41 

0 

Page. 

Tallow clay mine, description of .. .. . . .. .. .. .. .. . .. . .. 67 

Tar kiln mine, description of........................... 69 

Tertiary epoch, erosion during ........................ 31-32 

Thebes formation, correlation of . . . . . . . . . . . . . . . . . . . . . . 100 

Tiff, occurrence and character of. .... _ ....... _._...... 41 

Time scale, standard, of the Ohioan province, table... 90 

Tomahawk fault, description of .... _._ ......... _ ... _.. 37 

"Turkey fat" form of Smithsonite, cause of color of.. 40 

Ulrich, E. 0., determination and correlation of formations, paper on .................. __ ........ 90-113 

field work by...................................... 13 

Unconformities, enumeration of. ...................... 92-93 

VanHise, C. R., and Bain, H. Foster, cited on origin 

of ore deposits of Mississippi Valley._ ...... 88-89 

Van Ingen, Gilbert, cited on fauna of St. Clair limestone ...................................... _ 99 

Villines Creek, mines on .......................... _____ 85 

Viola limestone, correlation of. ... ...... . . _ ..... _ ... _ .. 97,98 

Virginia J. mine, description of ..................... __ 66 

Wallace Knob prospect, description of. ........... _ .. _. 79 

Washington shale and sandstone, stratigraphic place of. 109 

Water Creek, fold near ............. __ . __ ........ __ .. __ 39 

prospects on ....................................... 78,80 

Weathering, re!ations of, to cementation .. ______ ...... 35-36 

Wedington sandstone, character, occurrence, and thicknessof ..................................... 27 

correlation of .. .. .. . .. .. .. .. . .. .. .. .. .. .. .. .. .. .. .. 90 

stratigraphic place of ......... .. ....... ... _. . 107, 108-109 

Weller, Stuart B., Carboniferous fossils collected by . . 103 

cited on fauna of B~tesville sandstone .......... 104,105 

White, David, cited on age of coal-bearing shales..... 112 

White Eagle mine, description of .......... __ . _ ......• 74,75 

view of, plate showing ...................... __ .... 76 

White River, view of bottom land along ............. _ 16 

Yell ville formation on ....................... _ .. .. .. 19 

Wichita Belle prospect, description of. ..... _._._...... 83 

Williams, H. S., cited on correlation of Carrollton limestone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 

cited on fauna of St. Clair limestone ..... ___ ...... 98,99 

cited on Spring Creek limestone and its fauna .. 102, 103 

Willis mine, description of ......................... __ . 64 

Wilrockson, prospects near ............... _ . . . . . . . . . . . . 83 

Winchester mine, description of ......... __ ....... _.... 80 

Winslow formation, character, occurrence, and thickness of .......................... _ .. _ . . . . . . . 29 

correlation of...................................... 90 

Wyman sandstone, age of ........................ _ .. 104-106 

correlation of. ................. · ............ _ .. 90,104-106 

Yellville formation, character, occurrence, and thickness of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-20 

correlation of...................................... 90 

fossils of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93-95 

fracture zones in ................................. __ 33 

lower limit of ... ..... ... ...... . . ........ __ .. _ . . . . . . 95 

ore deposits in. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 

topographic expression of......................... 17 

Yellville quadrangle, area embraced by.............. 13 

boundaries of ..................................... _ 13 

faults in, description of. ........................... 36-39 

northern part of, geologic map of ......... : .. _.... 18 

southern part of, geologic map of.................. 20 

Zinc Basin prospect, description of ................... _ 73 

Zinc carbonate, occurrence and character of. .... __ ... 40 

Zinc ores, discovery of, reference to ............ _ ... _.. 14 

Zinc silicate, occurrence and character of ..... _ ...... 39-40 

Zinc sulphide, metallic zinc in ....................... _ 39 
PUBLICATIONS OF UNITED STATES GEOLOGICAL SURVEY. 

[Professional Paper No. 24.] 

The serial publications of the United States Geological Survey consist of (1) Annual Reports, 

{2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral Resources, (6) Water-Supply 

and Irrigation Papers, (7) Topographic Atlas of the United States-folios and separate sheets 

thereof, (8) Geologic Atlas of the United States-folios thereof. The classes numbered 2, 7, and 8 

are sold at cost of publication; the others are distributed free. A circular giving complete lists may 

be had on application. 

The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of subjects, and 

the total number issued is large. They }lave therefore been classified into the following series: A, 

Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; D, Petrography 

and mineralogy; E, Chemistry and physics; F, Geography; G, Miscellaneous; H, Forestry; I, Irrigation; J, \Vater storage; K, Pumping water; L, Quality of water; M, General hydrographic investigations; N, Water power; 0, Underground waters; P, Hydrographic progress reports. This paper 

is the thirty-first in Series A and the sixty-sixth in Series C, the complete lists of which follow. 

(PP=Professional Paper, B=Bulletin, \V'S= Water-Supply Paper.) 

SERIES A, ECONOMIC GEOLOGY. 

B 21. Lignites of Great Sioux Reservation: Report on region between Grand and Moreau rivers, Dakota, by Bailey Willis. 

1885. 16 pp., 5 pis. (Out of stock.) 

B 46. Nature an!i origin of deposits of phosphate of lime, by R. A. F. Penrose, jr., with introduction by N. S. Shaler. 1888. 

143 pp. (Out of stock.) 

B 65. Stratigraphy of the bituminous coal field of Pennsylvania, Ohio, and West Virginia, by I. C. White. 1891. 212 pp., 

11 pls. (Out of stock.) 

B 111. Geology of Big Stone Gap coal field of Virginia and Kentucky, by M. R. Campbell. 1893. 106 pp., 6 pis. 

B 132. The disseminated lead ores of southeastern Missouri, by Arthur Winslow. 1896. 31 pp. 

B 138. Artesian-well prospects in Atlantic Coastal Plain region, by N.H. Darton. 1896. 228 pp., 19 pis. (Out of stock.) 

B 139. Geology of Castle Mountain mining district, Montana, by W. H. Weed and L. V. Pirsson. 1896. 164 pp., 17 pis. 

B 143. Bibliography of clays and the ceramic arts, by J. C. Branner. 1896. 114 pp. c' 

B 164. Reconnaissance on the Rio Grande coal fields of Texas, by T. W. Vaughan, including a report on igneous rocks from 

the San Carlos coal field, by E. C. E. Lord. 1900. 100 pp., 11 pis. 

B 178. El Paso tin deposits, by W. H. Weed. 1901. 15 pp., 1 pl. 

B 180. Occurrence and distribution of corundum in United States, by J. H. Pratt. 1901. 98 pp., 14 pis. (Out of stock.) 

B 182. A report con the economic geology of the Silverton quadrangle, Colorado, by F. L. Ransome. 1901. 266 pp., 16 pis. 

(Out of stock.) 

B 184. Oil and gas fields of the western interior and northern Texas Coal Measures and of the Upper Cretaceous and Tertiary of the western Gulf coast, by G. I. Adams. 1901. 64 pp., 10 pis. (9ut of stock.) 

B 193. The geological relations and distribution of platinum and associated metals, by J. F. Kemp. 1902. 95 pp., 6 pis. 

(Out of stock.) 

B 198. The Berea grit oil sand in tB.e Cadiz quadrangle, Ohio, by W. T. Griswold. 1902. 43 pp., 1 pl. 

PP 1. Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska, by Alfred Hulse Brooks. 1902. 120 pp., 2 pis. 

B 200. Reconnaissance of the borax deposits of Death Valley and Mohave Desert, by 1\L R. Campbell. 1902. 23 pp., 1 pl. 

(Out of stock.) 

B 202. Tests for gold and silver in shales from western Kansas, by Waldemar Lindgren. 1902. 21 pp. 

PP 2. Reconnaissance of the northwestern portion of Seward Peninsula, Alaska, by A. J. Collier. 1902. 70 pp., 11 pis. 

PP 10. Reconnaissance from Fort Hamlin to Kotzebue Sound, Alaska, by way of Dall, Kanuti, Allen, and Kowak rivers, 

by W. C. Mendenhall. 1902. 68 pp., 10 pis. 

PP 11. Clays of the United States east of the Mississippi River, by Heinrich Ries. 1903. 298 pp., 9 pis. 

PP 12. Geology of the Globe copper district, Arizona, by F. L. Ransome. 1903. 168 pp., 27 pis. 

B 212. Oil fields of the Texas-Louisiana Gulf Coastal Plain, by C. W. Hayes and William Kennedy. 1903. 174 pp., 11 pis. 

B. 213. Contributions to economic geology, 1902. S. F. Emmons, C. W. Hayes, geologists in charge. 1903. 449 pp. 

PP 15. The mineral resources of the Mount Wrangell district, Alaska, by W. C. Mendenhall and F. C. Schrader. 1903. 

71 pp., 10 pis. 

B 218. Coal resources of the Yukon, Alaska, by Arthur J. Collier. 1903. 71 pp., 6 pis. 

B 219. The ore deposits of Tonopah, Nevada (preliminary report), by J. E. Spurr. 1903. 31 pp., 1 pl. 

·pp 20. A reconnaissance in northern Alaska in 1901, by F. C. Schrader. 1904. 139 pp., 16 pls. 

PP 21. The geology and ore deposits of the Bisbee quadrangle, Arizona, by F. L. Ransome. 1904. 168 pp., 29 pls. 

'B 223. Gypsum deposits in the United States, by G. I. Adams and others. 1904. 129 pp., 21 pls. 

PP 24. Zinc and lead deposits of northern Arkansas, by G. I. Adams, assisted by A. H. Purdue and E. F. Burchard, with a 

section on the determinat~on and correlation of formations, by E. 0. Ulrich. 1904. liS pp., 27 pis. · 
II PUBLICATIONS OF UNITED STATES GEOLOGICAL SURVEY. 

SERIES C, SYSTEMATIC GEOLOGY A~D PALEONTOLOGY. 

B 3. Fossil faunas of Upper Devonian, along the meridian 76° 30', from Tompkins County, New York, to Bradford 

County, Pennsylvania, by H. S. Williams. 1884. 36 pp. (Out of stock.) 

B 4. Mesozoic fossils, by C. A. White. 1884. 36 pp., 9 pls. (Out of stock.) 

B 10. Cambrian faunas of North America; preliminary studies, by C. D. Walcott. 1884. 74 pp., 10 pls. (Out of stock.) 

B 11. Quaternary and recent Mollusca of the Great Basin, with descriptions of new forms, by R. Ellsworth Call. Introduced by a sketch of the Quaternary lakes of the Great Basin, by G. K. Gilbert. 1884. 66 pp., 6 pls. 

B 15. Mesozoic and Cenozoic paleontology of California, by C. A. White. 1885. 33 pp. (Out of stock.) 

B 16. Higher Devonian faunas of Ontario County, New York, by J. M. Clarke. 1885. 86 pp., 3 pls. 

B 18. Marine Eocene, fresh-water Miocene, and other fossil Mollusca of western North America, by C. A. White. 1885. 

26 pp., 3 pls. 

B 19. Notes on the stratigraphy of California, by G. F. Becker. 1885. 28 pp. (Out of stock.) 

B 22. New Cretaceous fossils from California, by C. A. White. 1885. 25 pp., 5 pls. (Out of stock.) 

B 24. List of marine Mollusca, comprising the Quaternary fossils and Recent forms from American localities between 

Cape Hatteras and Cape Roque, including the Bermudas, by W. H. Dall. 1885. 336 pp. 

B 29. Fresh-water invertebrates of the North American Jurassic, by C. A. White. 41 pp., 4 pls. 

B 30. Second contribution to the studies on the Cambrian faunas of North America, by C. D. Walcott. 1886. 369 pp., 

33 pls. (Out of stock.) · 

B 31. Systematic review of our present knowledge of fossil insects, including myriapods and arachnids, by S. H. Seudder. 

1886. 128 pp. . 

B 34. Relation of the Laramie molluscan fauna to that of the succeeding fresh-water Eocene and other groups, by C. A. 

White. 1886. 54 pp., 5 pls. 

B 37. Types of the Laramie :fl.ora, by L. F. Ward. 1887. 354 pp. , 57 pls. 

B 41. Fossil faunas of the Upper Devonian-the Genesee section, New York, by H. S. Williams. 1887. 121 pp., 4 pls. (Out 

of stock.) 

B 43. Tertiary and Cretaceous strata of the Tuscaloosa, Tombigbee, and Alabama rivers, by E. A. Smith and L. C. Johnson. 

1887. 189 pp., 21 pls. 

B 51. Invertebrate fossils from the Pacific coast, by C. A. White. 1889. 102 pp., 14 pls. (Out of stock.) 

B 56. Fossil wood and lignite of the Potomac formation, by F . H. Knowlton. 1889. 72 pp., 7 pls. 

B 63. Bibliography of PalE;lozoic Crustacea from 1698 to 1889, including a list of North American species, and a systematic 

arrangement of genera, by A. W. Vogdes. 1890. 177 pp. 

B 69. Classed and annotated bibliography of fossil insects, by S. H. Scudder. 1890. iOl pp. 

B 71. Index to known fossil insects of the world, including myriapods and arachnids, by S. H. Scudder. 1891. 744 pp. 

B 77. The Texan Permian and its Mesozoic types of fossils, by C. A. White. 1891. 51 pp., 4 pls. 

B SO. Correlation papers-Devonian and Carboniferous, by H. S. Williams. 1891. 279 pp. (Out of stock.) 

B 81. Correlation papers-Cambrian, by C. D. Walcott. 1891. 447 pp., 3 pls. (Out of stock.) 

B 82. Correlation papers-Cretaceous, by C. A. White. 1891. 273 pp., 3 pls. (Out of stock.) 

B 83. Correlation papers-Eocene, by W. B. Clark. 1891. 173 pp., 2 pls. 

B 84. Correlation papers-Neocene, by W. H. Dall and G. D. Harris. 1892. 349 pp., 3 pls. (Out of stock.) 

B 85. Correlation papers-The Newark syste1p., by I. C. Russell. 1892. 344 pp., 13 pls. (Out of stock.) 

B 86. Correlation papers-Archean and Algonkian, by C. R. Van Hise. 1892. 549 pp., 12 pls. (Out of stock.) 

B 87. Synopsis of American fossil Brachiopoda, including bibliography and synonymy, by Charles Schuchert. 1897. 

464 pp. 

B 88. Cretaceous Foraminifera of New Jersey, by R. M. Bagg, jr. 1898. 89 pp., 6 pls. 

B 93. Some insects of special interest from Florissant, Colo., and other points in the Tertiaries of Colorado and Utah, by 

S. H. Scudder. 1892. 35 pp., 3 pls. (Out of stock.) 

B 97. Mesozoic 'Echinodermata of the United States, by W. B. Clark. 1893. 207 pp., 50 pls. 

B 98. Flora of the outlying Carboniferous basins of southwestern Missouri, by David White. 1893. 139 pp., 5 pls. 

B 101. Insect fauna of the Rhode Island coal field, by S. H. Scudder. 1893. 27 pp., 2 pls. 

B 102. Catalogue and bibliography of North American Mesozoic Invertebrata, by C. B. Boyle. 1893. 315 pp. 

B 105. The Laramie and the overlying Livingston formation in Montana, by W. H. Weed, with report on :fl.ora, by F. H. 

Knowlton. 1893. 68 pp., 6 pls. 

B 106. Colorado formation and its invertebrate fauna, by T. W. Stanton. 1893. 288 pp. ,45 pis. (Out of stock.) 

B 110. Paleozoic section in the vicinity of Three Forks, Mont., by A. C. Peale. 1893. 56 pp., 6 pls. 

B 120. Devonian system of eastern Pennsylvania and New York, by C. S. Prosser. 1895. 81 pp., 2 pls. (Out of stock.) 

B 121. Bibliography of North American paleontology, by C. R. Keyes. 1894. 251 pp. 

B 124. Revision of North American fossil cockroaches, by S. H. Scudder. 1895. 176 pp., 12 pls. 

B 128. Bear River formation and its characteristic fauna , by C. A. White. 1895. 108 pp., 11 pis. 

B 133. Contributions to the Cretaceous paleontology of the Pacific coast: The fauna of the Knoxville beds, by 'r. W. 

Stanton. 1895. 132 pp., 20 pls. 

B 134. Cambrian rocks of Pennsylvania, by C. D. Walcott. 1896. 43 pp., 15 pls. 

B 141. Eocene deposits of the middle Atlantic slope in Delaware, Maryland, and Virginia, by W. B. Clark. 1896. 167 pp., 

40 pls. 

B 142. Brief contribution to the geology and paleontology of northwestern Louisiana, by T. W. Vaughan. 1896. 65 pp., 

4 pls. 

B 145. Potomac formation in Virginia, by W. M. Fontaine. 1896. 149 pp., 2 pls. 

B 151. Lower Cretaceou11 gryphreas of the Texas region, by R. T. Hill and T. W. Vaughan. 1898. 139 pp., 35 pls. 

B 152. Catalogue of Cretaceous and Tertiary plants of North America, by F. H. Knowlton. 1898. 247 pp. 
• 

PUBLICATIONS OF UNITED STATES GEOLOGICAL SURVEY. 

B 153. Bibliographic index of North American Carboniferous invertebrates, by Stuart Weller. 1898. 653 pp. 

B 163. Flora of the Montana formation, by F. H. Knowlton. 1900. 118 pp., 19 pis. 

III 

~ 173. Synopsis of American fossil Bryozoa, including bibliography and synonymy, by J. M. Nickles and R. S. Bassler. 

1900. 663 pp. 

B 179. Bibliography and catalogue of fossil Vertebrata of North America, by 0. P. Hay. 1902. 868 pp. 

B 191. North American geologic formation names: Bibliography, synonymy, and distribution, by F. B. Weeks. 190:l. 448 pp. 

B 195. Structural details in the Green Mountain region and in eastern New York (second paper), by T. Nelson Dale. 1902. 

22 pp., 4 pis. • 

B 204. Fossil flora of the John Day Basin, Oregon, by F. H. Knowlton. 1902. 153 pp., 17 pis. 

B 205. The Mollusca of the Buda limestone, by G. B. Shattuck, with an appendix on the corals of the Buda limestone, by 

T. W. Vaughan. 1903. 94 pp., 27 pis. 

B 206. A study of the fauna of the Hamilton formation of the Cayuga Lake section in central New York, by H. F. Cleland. 

1903. 112 pp., 5 pis. 

B 210. The correlation of geological faunas; a contribution to Devonian paleontology, by H. S. Williams. 1903. 147 pp., 1 pl. 

B 211. Stratigraphy and paleontology of the Upper Carboniferous rocks of the Kansas section, by G. I. Adams, G. H. Girty, 

and David White. 1903. 123 pp., 4 pis. 

PP16. Carboniferous formations and faunas of Colorado, by G; H. Girty. 1903. 546 pp., 10 pis. 

PP19. Contributions to the geology of Washington, by G. 0. Smith and Bailey Willis. 1903. 101 pp., 20 pls. 

PP 21. The geology and ore deposits of the Bisbee quadrangle, Arizona, by F. L. Ransome. 1904. 168 pp., 29 pis. 

PP24. Zmc and lead deposits of northern Arkansas, by G. I. Adams, assisted by A. H. Purdue and E. F. Burchard, with a 

section on the determination and correlation of formations, by E. 0. Ulrich. 1904. 118 pp., 27 pis. 

Correspondence should be addressed to 

JUNE, 1904. 

4538--~o. 24--04----9 

THE DIRECTOR, 

UNITED STATES GEOLOGICAL SURVEY, 

WASHINGTON, D. C. 

LIBRARY CATALOGUE SLIPS. 

[Mount each slip upon a separate card, placing the subject at the top of the 

second slip. The name of the series should not be repeated on the series 

card, but additional numbers should be added, as received, to the first 

entry.] · 

Adams, George I [ rving] 

... Zinc and lead deposits of nortl;tern Arkansas, by 

George ·I. Adams, assisted by A. H. Purdue and E. F. 

~ Burchard, with a section on the determination and cor-

~ relation of formations, by E. 0. Ulrich. Washington, 

Gov't print. off., 1904. 

118, V p. illus., 27 pl. (incl. maps). 29! x 23cm. (U.S. Geological survey. 

Professional paper no. 24.) 

Subject series: A, Economic geology, 31; 0, Systematic geology and paleontology, 66. · 

A~ams, George I [ rving] 

. . . Zinc and lead deposits of. northern Arkansas, by 

George I. Adams, assisted by A. H. Purdue and E. F. ~ ;2 Burchard, with a section on the determination and cor-

: relation of formations, by E. 0. Ulrich. Washington, 

.. 

~ .. 

Gov't 'print. off., 1904. 

118, V p. illus., 27 pl. (incl. maps). 29!x 23cm. (U.S. Geological survey. 

Professional paper no. 24.) 

Subject·series: A, Economic geology, 31; 0, Systematic geology and paleontology, 66. 

U.S. Geological survey. 

Professional papers . 

: no. 24. Adams, G. I. Zinc and lead. deposits of northern Arkansas, by G. I. Adams, assisted by 

A. H. Purdue and E. F. Burchard, with a section on the determination and correlation of 

formations, by E. 0. Ulrich. 1904. 

~ U. S. J?ept~ of the Interior. ~ 

~ see also 

U. S. Geological survey. 

v