Pennsylvanian Carbonates, Paleoecology, 

and Rugose Colonial Corals, North Flank, 

Eastern Brooks Range, Arctic Alaska 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 

PENNSYLVANIAN CARBONATES, 

PALEOECOLOGY, AND RUGOSE COLONIAL CORALS, 

EASTERN BROOKS RANGE, ARCTIC ALASKA 
Panoramic view of the western Sadlerochit Mountains viewed to the east from 

the traverse of section 69A-1. The crest of the Sadlerochit Mountains and 

upper slope is formed by the dark-colored Permian and Triassic Sadlerochit 

Formation which overlies the medium-gray Mississippian and Pennsylvanian 

Lisburne Group. The angular unconformity between the Mississippian and the 

lighter Devonian carbonates is readily apparent in the center of the photograph. The Shublik Mountain::; are in the background. Photograph taken on 

.June 19, 1969. 
Pennsylvanian Carbonates, Paleoecology, 

and Rugose Colonial Corals, North Flank, 

Eastern Brooks Range, Arctic Alaska 

By AUGUSTUS K. ARMSTRONG 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 

Carbonate and paleoecological studies, and 

description of two new species of colonial rugose 

corals from four described sections of the Wahoo 

Limestone, Lisburne Group, Arctic Alaska 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1972 
UNITED STATES DEPARTMENT OF THE INTERIOR 

ROGERS C. B. MORTON, Secretary 

GEOLOGICAL SURVEY 

V. E. McKelvey, Director 

Librar;r of Congress catalog-card No. 72-600261 

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 - Price $1.00 (paper cover) 

Stock Number 2401-2150 
CONTENTS 

Page page 

Abstract __________________________________________ _ 1 Systematic paleontology-Continued 

Introduction ______________________________________ _ 1 Family Aulophyllidae Dybowski, 1873-Con. 

Previous work and acknowledgments _________________ _ 3 Corweniajagoensis n. sp ____________________ _ 10 

Biostratigraphy ____________________________________ _ 3 Family Lonsdaleiidae Chapman, 1893 ____________ _ 14 

Carbonate stratigraphy _____________________________ _ 3 Genus Lithostrotionella Yabe and Hayasaka, 

Environments of deposition _________________________ _ 6 1915 ___________________________________ _ 14 

Wahoo Limestone coral paleoecology _________________ _ 9 Lithostrotionella wahooensis n. sp _____________ _ 14 

Systematic paleontology ____________________________ _ 10 Graphic registry of stratigraphic sections and fossil 

Family Aulophyllidae Dybowski, 1873 ____________ _ 10 localities ________________________________________ _ 16 

18 

21 

Genus Corwenia Smith and Ryder, 1926, emend_ 10 Selected references _________________________________ _ 

Index ____________________________________________ _ 

ILLUSTRATIONS 

[Plates follow index] 

FRONTISPIECE. Panoramic view of the Lisburne Group outcrop, western Sadlerochit Mountains. 

PLATES 

FIGURE 

1-4. 

5. 

6. 

7. 

8. 

1. 

2-5. 

Corwenia jagoensis n. sp. 

Lithostrotionella wahooensis n. sp. and Corwenia jagoensis n. sp. 

L1'thostrotionella wahooensis n. sp. 

Lz:thostrotionella wahooensis n. sp. and photomicrographs of carbonate rock types in sections 69A-1, 68A-4A-4B. 

Photomicrographs of carbonate rock types in sections 68A-5, 68A-1. 

Index maps and biostratigraphic sections of the Wahoo Limestone_______________________________________ 2 

Photograph of2. West Sadlerochit l\Iountains section 69A-L_______ _ __ __ __ __ ___ ___ __ __ ___ _____ __ _______ _ __ _ _ _____ 4 

3. Lisburne Group outcrop to the east of East Sadlerochit ::vlountains sections 68A-4A-4B _ _ _ _ _ _ _ _ _ _ _ _ _ 5 

4. Egaksrak River section 68A-5 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5 

5. The unconformity between the Wahoo Limestone and Sadlerochit Formation_______________________ 6 

6. Composite and idealized section of the Lisburne Group, Sadlerochit Mountains, showing carbonate depositional 

cycles_________________________________________________________________________________________ 7 

7. Block diagram showing Pennsylvanian environments of deposition of the Wahoo Limestone_________________ 9 

8. Graph showing corallite diameter and nmnber of major septa in Corwenia jagoensis n. sp _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 11 

9. Photograph of large corallum of Corwenia jagoensis n. sp. in outcrop, showing shape of colony and corallite 

growth_______________________________________________________________________________________ 12 

10. Graph showing corallite diameter and number of major septa in Lithostrotionella wahooensis n. sp____________ 15 

11-16. Location maps: 

11. Ikiakpuk River section 68A-L _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 17 

12. West Sadlerochit Mountains section 69A-L_ _ _ _ ___ _ _ _ _ _ _ _ __ _ _ _ _ _ __ __ _ _ _ _ __ _ _ _ _ _ _ _ __ _ _ _ __ _ _ _ _ _ _ _ 17 

13. East Sadlerochit Mountains sections 68A-4A-4B________________________________________________ 17 

14. Egaksrak River section 68A-5 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 17 

15. Central Sadlerochit Mountains section 68A-3___ _ __ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ __ _ _ ___ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ __ _ __ _ 18 

16. West Shublik Mountains section 69A-2________________________________________________________ 18 

v 

PENNSYLVANIAN CARBONATES, PALEOECOLOGY, AND 

RUGOSE COLONIAL CORALS, 

NORTH FLANK, EASTERN BROOKS RANGE, 

ARCTIC ALASKA 

By AucusTus K. ARM•STRONG 

ABSTRACT 

The Pennsylvanian carbonates of four measured sections of the 

Late :\Iississippian and Pennsylyanian \Vahoo Limestone consist 

of 310-1,250 feet of deposits of the Lislmrne Group. Shallowwater open-marine carbonates of }lorrow age overlie, without 

hiatus, restricted marine to intertidal dolomitic carbonates of the 

Alapah Limestone of latest }Iississippian age. The Morrow-age 

carbonates are predominately echinoderm-bryozoan wackestones 

and packstont>s, with minor amounts of ooid grainstones and 

lime mudstones. 1.'he Atoka age carbonates are in part crossbedded bryozoan-echinoderm and oolitic grainstones, 'vith associated minor amounts of thin-bedded dolomites. Outcrops of the 

Wahoo Limestone in the Sadlerochit }Iountains indicate that 

Pennsylyanian sedimentation from }forrow to Atoka time generally vrogressed from shallow-water 011en-marine sedimentation 

to higher-energy shoaling water oolitic sedimentation. 

'J'he Atoka age rugose colonial corals, OorweniCl jagoensis 

n. sp. and Lithostrotionella wahooensis n. sp., are described. 

Paleoecological and biostratigraphic analysis of the carbonate 

beds associated with the colonial corals indicates that they lived 

in clear agitated water between oolitic tidal bars. 

INTRODUCTION 

Pennsyh·anian carbonates are well exposed in northeastern Brooks Range (see frontispiece) of eastern 

Arctic Alaska. The outcrops are suitable for detailed 

stratigraphic, facies, and paleoenvironmental studies. 

Also, a few other localities at certain stratigraphic levels 

contain large numbers of colonial corals. The location 

of the study area is shown in figure 1. 

The four stratigraphic sections discussed in this report were 1neasured with a Jacob's sta.ff and tape. 

Lithologic and fora1niriiferal samples were collected 

every 5-10 feet. ~Iost of the corals were collected from 

within measured sections. Thin sections, cut from lithologic samples, were petrographically described ~and 

studied for microfossiles. 

Calcite and dolomite were identified in thin sections 

by the Alizarin-red staining techniques of Friedman 

( 1959). The carbonate classification is that of Dunham 

( 1962). 

The sedimentary features and structures used in this 

study to delineate enviromnents of deposition and 

paleoecology are described in detail by Logan, Rezak, 

and Ginsburg (196±), Shinn, Ginsburg, and Lloyd 

(1965), Roehl (1967), '¥"ilson (1967a, b, 1969), Shinn 

(1968a, b), Ball, Shinn, and Stock1nan (1967), Ball 

(1967) ~ and ~Iurray and Lucia (1967). The concepts 

for cyclic carbonate deposition cyclic which are used in 

this report are those developed by Fischer (1964), Wilson (1967a, b), Coogan (1969), Armstrong (1967), and 

Armstrong, Macl{evett, and Silberling ( 1969). 

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FIGURE 1.-Inclex map of ..Arctic AlaHka and a generalized location map of the measured sections of the Wahoo Limestone in northeastern Alaska, with a graphic exr1lanation of the lithologic and fossil symbols used in this report. The stratigraphic position of 

the cornls described in this study is also shown. Detailed location maps of the stratigravhic sections are given in figures 11-16. 
CARBONATE STRATIGRAPHY 3 

PREVIOUS WORK AND ACKNOWLEDGMENTS 

In 1962, Brosge, Dutro, Mangus, and Reiser extended 

the name Lisbume Group to car·bonatc rocks at \Vahoo 

Lake and inclllCh~d in it the Em·ly Mississippian \Vachsmuth Limesto11P, the Late Mississippian Alapah Limestone, and the newly named Pennsylvania( n and Permian \Vahoo Limestone. The \V•ahoo Limestone, as 

mapped in the a rPa of this rt>p01·t, contains some beds ~f 

very latest Chester (latest Mississippian) ag~ but primarily contains beds of MorTo\\· (Early Pennsyl ,·anian) 

and Atoka (Middle Pennsy l n1nian) age and does not 

contain strata of Permian agP. Armstrong, Mamet, and 

Dutro ( 1070), using microfossil zones, divided the 

Lisburne Group of central and eastem Brooks Hange 

into a series of biostratigraphic units and defined the 

base of the Pennsylvanian System in the Brooks Hange. 

Detailed accounts of the history of the study of the Carboniferous rocks of the Lisburne Group can be found 

in Bowsher aml Dutro (HJi>7) and Armstrong, Mamet, 

and Dutro (1970). Reiser, Dutro, I3rosge, Armstrong, 

and Detterman (1970) haYc made geologic maps 1: 63,-

:160 scalP) of the Sadlemchit Mountains that delineate 

the outcrops of the Lisbume Group, including the 

\Yahoo Limestone. 

I wish to express my appreciation to In,in Taillenr, 

party chief during the summer of 1968, and Hillard N. 

Heiser, party chief during the summers of 196!) and 

1070, for their generosity in supporting my coral collectino· and stratigraphic studic·s. I \Yish to thank the N·aval 

\..~ctic. Hesea rch La bora tory ( Ba ITO\V), office of ~a val 

Hesearch, for their logistical support of my fieldwork 

durino· the summers of 1968-70. Two specimens of 

coloni~l corals used in this study, collected by Shell Oil 

Co. geologists in 1960 and 1963, \Yerc given to the U.S. 

Geological Suncy, and 'appreciation is expressed toR. 

E. McAdams and G. E. Bmton, .-ice-presidents of Shell 

Oil Co. The photographs and thin sections were made 

by Kenj i Sakarnoto and Robert ShPly, respecti ,·ely, both 

of the V.S. Geological Suney. 

I am grateful to my colleagues, J. Thomas Dutro, ,Jr., 

\Villiam J. Sando. and \Villiam A. Oliver, Jr., who 

helped in preparation of the manuscript and provided 

critical review. James Lee \Vilson helped in the development of concepts relating to the environments of deposition and paleoecology and also reviewed the stratioTaphic parts of the manuscript. I wish to thank Mahlon .M. Ball and Robert Ginsberg for their review of 

the manuscript. 

BIOSTRATIGRAPHY 

Armstrong, Mamet, and Dutro ( 1970, 1971) and 

Armstrono· and Mamet (1970) have described the sequences of Mississippian and Pennsylvanian biostratigraphic zones within the Lisburne Group of Arctic 

Alaska; these biostratigraphic zones are based on the 

microfossil zones developed by B. L. Mamet. 

\Vithin the area of this study, the Lisburne Group 

consists of the Alapah Limestone and ·wahoo Limestone. The basal Alapah Limestone at the Ikiakpuk section (68A-1) in the Fourth Hange is of Mer~mec (Late 

Mississippian) age (zone 13); to the north. m the Sa~­

lerochit Mountains at the \iV est Sadlerochit Moun tam 

section ( 69A-1) , the base is lower Chesteran ~zone 1~i). 

The microfossils indicate that carbonate sedunentatwn 

continued without a significant or recognizable hiatus 

into Pennsylvanian time. In the Mamet zonal scheme, 

the base of the Pennsylvanian system is at the base of 

zone 20 and is defined on the first occurrence of the Morrow fossils, Endothyra of the group E. nwsquensis Re~t

linger·, Lipinella, sp., JJfillerella sp., and Neoarchaediscus gnmdis ( Reitlinger). Atokan age (zone 21) carbonates contain the microfossils Olimacam1nina cf. 0. moelleTi Reitlinger, Eoschubertella sp., Pseudostaff'ella sp., 

and Globi1.,•alvulina sensu stricto. The absence of FusuZinella spp. and Profusulinella spp. is a serious detriment to exact correlation with other established Pennsylvanian sections. The presence of these genera would 

substantiate the conclusion that the uppermost beds are 

not Des Moines in age. 

Hugose corals are known only from beds of Atoka 

age of the \Vahoo Limestone; as yet none has been 

found in beds of Morrow age. The corals are represented by two new species, Oorwenia jagoensis n. sp. 

and Lithosh'otionella walwoensis n. sp. The most closely 

related corals are Dithost?'otionella orboensis Groot 

(1963) from the upper Moscovian of Spain and Petalamis mohikana Fomichev (1953) from the upper .Moscovian of the Donetz Basin, U.S.S.R Oorwenia jagoensis n. sp. shows close similarity to the upper .Moscovian 

corals Oonoenia symmetrica (Dobroljubova) from 

Spain and Moscow and Donetz Basins of U.S.~.R Taxa 

similar to L. 1oahooensis have not been descnbed from 

Pennsylvanian age sediments of the Cordille~an r~gion. 

of North America. The apparent closer relatwnslup of 

the two Atokan-\Vahoo corals to forms described from 

Eurasia is probably due to the lack of detailed systematic studies on Pennsylvanian colonial corals from the 

Cordilleran of North America. 

CARBONATE STRATIGRAPHY 

Brosge, Dutro, Mangus, and Heiser (1.962, p. 2191) 

described the type section of the vVahoo Limestone near 

\Vahoo Lake as containing carbonates of Pennsylvanian (?) and Permian age. In the are~ of this report, tl~e 

\Vahoo Limestone as mapped by Heiser, Dutro, Brosge, 

Armstrong, and Detterman (1970) c.ontains carbonates 
4 PB.:-<NSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

of ~{ississippian (very latest Chester) and Pennsylvanian (Morrow and Atoka) age (fig. 1). The Pennsylvanian lirnestones oYerlie ~Iis issippian (latest Chester) carbonates without a recognizahle hiatus. The 

boundary between the two systems and tl1e zones within 

them arc based on microfauna] assemblages (Armstrong and others, 1970). The Atokan beds are unconformably overlain by arenaceous limestones, sandstones, 

and conglomerates of the Sadlerochit Formation of 

Late Permian and Early Triassic age. 

ln the area of this paper (fig. 1), the \Yahoo Limestone forms bold cl iffs (figs. 2, B) above the thin-bedded, 

generally talus-covered slopes of Alapah Limestone 

(l\iississippian). 

The :Morrow age carbonates (fig. 1) of the Wahoo 

Limestone arc predominantly bryozoan-crinoid wackeFIGL"RE 2.- West Sadlerochit :\fonntltins section (69.-\-1) sho\Y· 

in~ line of tnlH'l'Se and stratigraphic footage marks. 'l'he eontact lJeh,·een the thin-lleudecl dolomitic ear bonn tes of the Alapah Limestone anrl the massiYe limestone of the "'ahoo Limestone is sho\Yn at 310 feet. Locality of 'the type specimf'n of 

LithostroUonella wahooens-is n. sp. is indicated. The contact 

stones and packstones (pl. 7, figs. 4, 8; pl. 8, figs. 4-6). 

The fossil fragments are typically large, 0.2-5 mm in 

length. and poorly sorted. Lesser amounts of grainstones 

formed of well-sorted fossil fragments and superficial 

ooids are present (pl. 7, figs. 6, 7). Thick-bedded lime 

mudstones and extensi ,-ely clolomitizcd carbonates arc 

absent in the MOJTowan and Atokan beds. 

In the \Vest Sadlerochit Mountain section 69A-1, the 

por·tion from 150-800 feet (pl. 7, fig. 5) below the SadlProchit Formation is composed of coarse-grained bryozoan-eel! inodcrm packstones which form 25- to 50-footthick heels (fig. 2). Lenticular to nodular brown to 

brownish-gray rhert is abundant. Similar intervals of 

MoLTow age in the East Sadlerochit Mountain section, 

68A_-4A-4R, however, contain a higher percentage of 

winnowed sediments in the form of ooid packstones, 

of the Permian and Triassic Sadlerochit Formation is sho~n1 

ill the right center of the photogravh. 'l"he df'w is to the south ; 

ill the lmckgrounrl nrP the Shubli k ::\[ountnins. The \YellexposPrl l'Pnnsyl\'anian-l'el·mian unconformity shown in figure i:i is located a few hundred yards to the right of the contact shown in this photograph. 
CARBONATE STRATIGRAPHY 5 

FIGURE 3.-The Lisburne Group outcrop on the hillside to t he 

eas't and opposite the line of traverse of East Sadlerochit 

:\fountains section ( 68A-4A-4B) . Thin-bedded dolomites near 

the 'top of the Alapah Limestone form the rublJle-covered slope 

lJeneath the massiYe cliffs of the Wahoo Limestone which 

begins at the 860-foot mark. The basal lJeds of the Wahoo 

Limestone are of late Chester age. The varied topographic expression of the Li~-'l.Jurne Group clearly reflects the several 

carlJonate rock types formed in differing ancient depositional 

em·i ronmen ts. (See fig. 6.) 

grainstones, and pelletoidal-bioclastic packstones and 

grainstones (pl. 7, figs. 6, 7). The Morrow age carbonates to the east in the Egaksrak River section 68A-5 

(fig. 4), are again low-energy bryozoan-crinoid' wackestones and packstones (pl. 8, figs. 4-6) with only minor 

amounts of superficial ooids and oolitic grainstones. 

The Atoka age cat'bonates are predominantly grainsupported packstones and grainstones with minor 

amounts of wackestone and lime mudstones. Characteristically these beds are 5- to 15-foot thick, weakly crossbedded, well-stratified oolitic grainstone which contains 

well-developed ooid grains (pl. 8, figs. 2, 7) that are 

from 0.5 to 1.0 mm in diameter. Some of the ooids have 

numerous layers and many show much evidence of alo-al 

boring. The nuclei of many of the ooids are rounded f~s sil fragments. Associated with the ooids are superficial 

ooids and rounded and coated lithoclasts from 1 to 4 mm 

in length. Commonly occurring with these grainstones 

are abundant Foraminifera and calcareous algae. The 

bryozoan-crinoid grainstones and packstones are formed 

by Formaminifera and broken 'bryozoan fragments 

whose interiors are generally filled with micrite (pl. 8, 

figs. 3, 4). A small percentage ( 1-2 percent) of these 

fossils have glauconite filling t he internal spaces. The 

carbonates bebYeen some of the oolite beds are 6-ine'h to 

4-foot thick, argillaceous, arenaceous, dolomitic, and 

hematitic. These "marker~' beds persist oYer long distances in the Sadlerochit and Shublik Mountains and 

gi\·e the '\Yahoo Limestone its characteristic yellowishorange weathering color. Thin sections of the carbon-

"" I Base of continuous section 

f 

FIGURE 4.-The Egaksrak River section (68A- 5), showing the 

contact of the Sadlerochit Formation with the underlying 

Wahoo Limestone and the rubble-covered slope at the base of 

'the section. The sec'tion was measured over the crest of the 

ridge. The Gorwenia jagoen8i8 n. sp. zone, named for the prolific species, occurs on 'the apex of the hill. View is to the 

east. 

ates which form these "marker" beds show their composition to be 50-70 percent dolomite rhombs ranging 

from 25 to 50 microns and the remainder fragmental 

subangular grains of detrital quartz ranging from 50 to 

100 microns. Limonite and hematite fill the interstices 

between many of the dolomite rhombs. The iron oxides 

probably are the weathering products of pyrite. Associated with the grainstones are thicker nonlimonitic lime 

mudstones and wackestones which contain 5-30 percent 

detrital quartz whose grains range from 50- to 100-

microns. Glauconitic shale pmtings, 1- 4 inches thick, are 

not uncommon between the massive carbonates. 

Atoka age carbonates are a!bout 700 feet thick at the 

Egaksrak River section. Bryozoan-echinoderm wackestones and packstones are the dominant rock types from 

0 to 400 feet below the top of the section. Within this 

interval true oolites are rare, but oolites are sporadically 

present from 410-570 feet below the top. Oolitic grainstones are well developed from 590 to 600 feet below the 

top of the section (pl. 8, fig. 2). Within the Egaksrak 

section the spherical algal-foraminiferal colonies of 

Osagia sp. are locally common at 160, 560, and 615 feet 

below the top of tl1e section. Osagia sp. has also been 

found in the East Sadlerochit Mountain section 68A4.-\.-4B at 40-50 and 120-130 feet below the top. 

Tlte Ikiakpuk section, 68A- 1, in the Third Range, is 

so nth of the above sections (fig. 1). The section was 

measured on a series of exposures in stream-cut banks. 

Here the Pennsylvanian '\Yahoo Limestone is some 375 

feet thick. The Atoka beds are about 135 feet thick and 

are formed 'by tectonically stressed ooid foraminiferal 

grainstones (pl. 8, figs. 7, 8). The underlying Morrow 
6 PENNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

beds also show grain growth due to tectonic stress and 

are bryozoan-echinoderm packstones and grainstones. 

In the area of this study, the P ermian and Triassic 

Sadlerochit Formation conformably overlies limestones 

of Atoka age. Detterman ( 1970) reports that the basal 

Echooka Member of the Sadlerochit Formation contains a brachiopod fauna of early Kazanian (earliest 

Late P ermian) age. The unconformity (fig. 5) represents a hiatus of Des Moines through Leonard, and possibly early Guadalupe, time. The westward thinning of 

the Atoka age carbonates in the Sadlerochit Mountains 

(fig. 1) suggests uneven erosion, probably caused by 

differential uplift previous to sedimentation of the Sadlerochit Formation. At many localities the highest few 

feet of Atoka age carbonates beneath the Sadlerochit 

Formation show evidence of vadose weathering in the 

form of enlarged vertical joints and vugs filled with a 

terra rossa-like clay (fig. 5). The basal beds of the 

FIGURE 5.-Contact between Atok a carbonates of the 'Vahoo 

Limestone and Permian sandstones of the Sadlerochit Formation (upper arrow). Large eobbles and smaller pebbles of 

'Vahoo Limestone are present at the base of the Sadlerochit 

Formation. Cracks and solution joints (lower arrow) in the 

upper part of the 'Vahoo Limestone are tilled b:r a terra rossalike day. The hiatu~ bet\\"een the 'Vahoo Limestone and Sadlero('hit Formation rf'presents a ll of Des :\Ioines, l\Iissouri, 

Virgil, and Early Permian time. The ruler is 6 inches long. 

Echooka Member are conglomerates or conglomeratic 

sandstone formed in part of rounded chert and limestone pebbles and cobbles derived from the underlying 

\Yahoo Limestone. 

ENVIRONMENTS OF DEPOSITION 

\Vithin the area of this study, the vVahoo Limestone 

is part of a two-phase carbonate depositional megacycle 

which began in Late Mississippian time and continued 

into Pennsy: van ian time (fig. 6). This carbonate sedimentation is part of a regionally transgressive Lisburne 

Group sequence that began at the Ikiakpuk section 

( 68A - 1), Third Range, in Meramecian time (zone 13) 

and at the \Vest Sadlerochit Mountain section (69A- 1) 

in Chesteran (zone 16i) time (Armstrong and others, 

1970). Above the Kayak ( ?) Shale the basal Late Mississippian Alapah limestones are typically well-sorted 

pelletoidal-bioclastic-grainstones and packstones and 

lesser amounts of ooid grainstones. Overlying these are 

beds of poorly sorted noncurrent-deposited bryozoanechinoderm packstones and \Yackestones. The environment of deposition for these carbonates is interpreted as 

open platform, normal marine (figs. 6, 7). The lithology 

and sedimentary structures of the higher beds of the 

Alapah Limestone clearly indicate a progressively more 

restricted marine environment of deposition and the development of a regressive sequence of carbonates. 

These younger beds show a progressive decrease in 

biotic di ,.e,·sity, an increase in the amounts of pelletoida.l 

packstones and lime mudstones, and an increase in the 

percentage of dolomite. This regressi\·e sequence is ,·ery 

well developed in the East Sadlerochit :Mountain section, 68A-4A.-4B, (fig.l). At a level950 feet below the 

top of the section, the Alapah Limestone is a finegrained light-brown-gray cherty dolomite with wellde\·eloped algal mat and birdseye structure; these 

features indicate deposition in very shallow marine to 

intertidal e1wironments. A similar sequence of rock 

types can be seen in the Alapah Limestone at Ikiakpuk 

Creek and in the \Vest Sadlerochit Mountains sections. 

The latter exposure has, at the same general stratigraphic level, restricted marine sediments of somewhat 

dolomitized thin-bedded pelletoidal packstones but is 

de,·oid of algal mats. The restricted marine shallow 

\Yater to intertidal carbonates in the upper beds of the 

Alapah Limestone are generally thin bedded and platy, 

and they form talus slopes beneath the massiye limestones of the \Yahoo Limestones (figs. 2, 3). 

This regressiye suite of carbonates (fig. 6) which 

culminates in an intertidal-restricted marine facies is 

overlain, as indicated by microfossil assemblages (Arm-
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ENVIRONMENTS OF DEPOS1ITION 7 

Environments of deposition strong and others, 1970), by a marine transgressive carbonate facies of bryozoan-eehinoderm wackestones and 

packstones eontaining mierofossils of latest Chester age 

(zone 19). In the area of this report, this second earbonate transgressive cyele of the Lisburne Group began in 

latest Chester time and eontinued aeross the Mississippian-Pennsylvanian boundary without a hiatus (fig. 6). 

The earliest ~forrow age carbonates are lithologica.lly 

similar to those of very latest Chester age and are bryozoan-echinoderm wackestones and paekstones that were 

probably deposited on an open Inarine platform. The 

outcrops of the 'V ahoo Limestone in the Sadlerochit 

~fountains indicate that, from the base of the Pennsylvanian to the unconformity at the base of the Permim1, 

the general trend in sedi1nentation is towards higher 

energy water, that is a shoaling water oolitic. environInent of deposition. This is inferred from the stratigraphieally higher beds whieh eontain less mierite, a 

more diversified biota, better-sorted fossil fragments, 

and many beds with well-developed ooids. For the 

Sadlerochit Mountains, the interpretation of this shift 

in environments of deposition from the early Chester to 

Atoka time is graphically illustrated in figure 6. 

(/) 

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The Wahoo Li1nestone echinoderm-bryozoan packstones and grainstones have 0.5-2 pereent bright green 

glauconite grains, most of it oeeurring as internal 

fillings in Foraminifera and bryozoan fragments and 

occasionally as free grains. Cloud (1955) and LoehmanBalk (1957) give detailed aeeounts on the environments of deposition and physical limits of gl~auconite 

formation. In general these are : normal salinity, slightly redueing eonditions at sites of origin~ bottom sediments rich in organic material, a water depth greater 

than 25 feet~ and low terrigenous sediment influx. The 

presence of glaueonite in the bryozoan-eehinoderm 

grain-supported carbonates suggests that the glaueonite 

formed in a redueing environment in elose juxtaposition 

to oxygenated '\Vaters in whieh bryozoans and erinoids 

thrived. The materials from these two environments 

were brought together by the activities of ehurning and 

burrowing organisms and by the ehanneling, reworking, and sorting activities of tidal ehannels (diagrammatieally shown in fig. 7). 

FIGURE 6.-Composite and idealized Lisburne Group sequence in 

the Sadlerochit Mountains showing the interpreted shifts of 

carbonate environments of deposition at various stratigraphic levels. Explanation of symbols for fossil particles 

given in figure 1. 
8 PENNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

._,.-----Salinity increases------

Intertidal-supratidal; Restricted platform; bioclastic I Open ~latform; normal marine, I imited fa~na, bi?-

lime. mudstones-do-~ wackestones i.n lagoon~ and clast1c. w~ckestones and packstones; b1oclast1c 

lom1tes-algal mats bays; bioclastic sands 1n t1d- sands 1n t1dal channels 

al channels Mean sea level 

J atnes Lee Wilson (written commun., March, 1971) 

states 

The presence of glauconite in grainstones is common in carbonate rocks all over the world despite the fact that i't is a 

mineral of reducing environment. Stratigraphic observation and 

studies indicate that glauconites are associated with zones of 

slow deposition, often forming in strata which are overlain later 

by an unconformity. It seems reasonable that under a situation of 

Yery slow deposi'tion, conditions exist for the organic reworking of sediment as well as mechanical reworking. Grains are carried down into the substrate in a reducing environment in which 

iron is concentrated (probably also by slow intermi'ttent deposition during 'vhich time no clastic material is introduced 'to mask 

it). Later such grains are brought up and exposed to current 

and wave action by marine channeling an'd further burrowing; 

during the in'terim of burial glauconite has formed from the mud 

and organic slime caught wi'thin the grains while they have remained buried. The 'Vahoo Limestone glauconitic grainstones 

tell us that not only slow deposi'tion prevailed but that sufficient 

mud occurred in between oolite bars to create impermeability 

and a reducing iron-rich environment. Most pore-filling glauconite is basically a product of organic feces in the mud. These 

ideas derive in part from discussions with H. B. Stenzel. 

The oolitic grainstones which are found in association with the glauconitic grainstones are well-stratified, 

generally 5-10 feet thick, and poorly crossbedded. In 

many places, the beds are capped by dolomites whieh are 

frmn 6 inches to 2 feet thick, argillaceous, arenaceous, 

and limonitic.; the dolon1ites weather to pale yellowish 

orange. This roek is eomposecl of dolomite rhmnbs some 

30 microns in size and with more than 30 percent siltsize detrital quartz. BalFs (1967) description of modern 

earbonate. sand bodies indieat~. that the Wahoo oolite 

grainstones were probably formed in a tidal bar belt environment transgressive over the underlying sediments 

that are eharaeteristic of an open platform normal marine environment "\vhich is probably slightly reducing 

and glauconite-forming. The thin-bedded pale yellowish orange-weathering arenaceous dolomites and the 

thick-bedded oolitic grainstones are interpreted as representing the interstratified record of very shallow lime 

mud tidal flats developed directly over oolitic tidal bars. 

This close physical relationship of oolitic grainstones 

and thin -

1

bedded lime mudstones and dolomites is not 

unique to the Wahoo Limestone. Wilson, Madrid-Solis, 

and Malpica-Cruz (1967, p. 81) report a simila.r sequence of oolitic grainstone and unfossiliferous mudstones from Pennsylvanian carbonates of southwestern 

New Mexico. J. L. Wilson (written commun., 1971) 

states that similar 

dolomitic marker beds are also common in Devonian and Mississippian sections of Montana where they are almost certainly 

tidal flat and sebkha deposits 'vi'th the former sulfate minerals 

leached out. In places such beds are de-dolomitized. In Montana in the Mission Canyon Limestone such beds are a:lso associated with oolitic grainstones but are commonly separated fron1 

these by a transitional zone of birdseye pelletoidal mudstone and 

grainstone. 

The EO'aksrak River section has 400 feet of ooid b 

to echinoderm-bryozoan paekstones-wackestones and 

grainstones above the highest well-developed oolite 

grainstones (fig. 1). These carbonate beds are believed 

to be a younger Atoka age than those carbonates preserved beneath the Permian unconformity in the Sadlerochit Mountains. 

Osagia sp. eolonies occur at 160, 560, and 600 feet 

below the top of the Egaksrak River seetion and possibly indicate a very shallow water environ1nent of deposition. These beds also eontain increasing amounts of 

micrite and significant amounts ( 5-20 percent) of siltto fine-sand-size detrital quartz. These factors possibly 

indicate that the beds above the last oolitic grainstone 

represent the development of a slowly regressive carbonate depositional phase. 
WAHOO LIMESTONE COR,AL PALEOECOLOGY 9 

I 

Shoal; lime sands and oolites bryozoan-echinoderm wackestones-~ 

packstones and crossbedded grainstones; superficial ooid and 

ooid packstones-grainstones; Osagia grainstones 

Open platform; normal marine, fauna of brachiopods, 

bryozoans, crinoids; bryozoan-echinoderm wackestones and packstones 

~ 

Environments of abundant 

rugose corals 

Algal mats 

EXPLANATION 

Current deposited 

EZ3 

Oo I i tic-superficial 

ooid grainstones 

Bryozoan-crinoid 

~ 

~ 

grainstones 

Noncurrent deposited 

Bryozoan-crinoid 

~l 

~ 

packstones-wackestones 

~ 

~ 

Lime mudstone and pelletoid packstones 

Dolomitic I ime mudstones 

and dolomites 

FIGURE 7.-The Pennsylvanian environments of carbonate deposition of the W11hoo Limestone on the north flank, eastern Brooks 

Range. Yertical distance is less than 100 feet. horizontal distance 50-100 miles. 

WAHOO LIMESTONE CORAL PALEOECOLOGY 

The colonial corals, Corwenia )agocn8i8 n. sp., and 

Litlw8trotionel7a wahooewsi8 n. sp., occur in large nmnbers in certain horizons of the "'Vahoo Limestone. Their 

growth habit and spatial relationship within these beds 

indicates that individual colonies lived separated from 

each other and did not forn1 biostromal or biohermal 

masses. 

The colonial corals in the Wahoo Limestone are 

found in close association with oolitic grainstones and 

packstones. The specimens are not found generally in 

carbonates n1ade entirely of ooids but in ooid admixtures that have varying amounts of micrite, pellets, 

small lithoelasts, and abundant fragments of brachiopods, bryozoans, echinoderms, calcareous algae, fusulinids, and smaller foraminifers. This rich and diverse 

biota indicates a shallo,v-water environment. The abundant fragments of calcareous algae and well-developed 

ooid grains, 0.4-0.8 mm in size, indicate deposition in 

or adjacent to shoaling water. The presence of micritie 

lithoclasts, as n1uch as 4 mm in size, and pore filling by 

lime mud indicate a somewhat lower energy environInent than simple ooicl tidal banks. In the Bahamas 

1 ithoelasts are n1ost common in the, tidal channels and 

interbar S\Yales. The environments of coral growth are 

probably below and to the side or between the oolite 

banks but above the reducing environments in which 

the glauconite was fm'lned. :Many of the cor·alla appear 

to have been buried in a growth position, but others appear to have been turned over and broken before burial. 

These latter factors plus the lithoclasts found associated 

with .the eorals suggest periodic high-energy \Vave motion, whieh was probably associated with storn1 activity 

(Ball and others, 1967). The origins of these micriticpelletoidal bioelastic-oolitic packstones are somewhat 

analogous to similar calcareous sand bodies of the Bahama Banks described by Ball (1967, fig. 9, particularly 

fig. 19). A hypothetical reconstruction of the Wahoo 

Limestone environments of deposition is shown in figure 7, and the preferred environments for coral growth 

are shown as between and below the ooid sand tidal 

bank. 
10 PENNSYLVANIAN CARBONATES, PALE·OECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

The association of colonial rugose corals with grainstones having oolites indicates that they needed a rela.-

tively high-energy clear shoaling-water environment. 

The general absence of corals from the packstones and 

grainstones which are interstratified with the ooid-bearing beds but which lack oolites provides evidence that 

these corals tolerated a narrow range of environments. 

The Pennsylvanian rugose colonial corals of the Lisburne Group appear to be ·more environmentally sensitive than the ~fississippian (Meramec) lithostrotionoid 

corals of the older parts of the Alapah Limestone of 

the Brooks Range. These older rugose corals, as indicated by the rock record, could tolerate slower 1noving 

water with apparently higher amounts of suspended 

lime mud particles. Annstrong (1970) reported that in 

the Kogruk Formation, DeLong ~fountains, the lithostrotionoid corals are abundant in ooid grainstone and 

are common in bryozoan-crinoid packstones and 

wackestones. 

SYSTEMATIC PALEONTOLOGY 

Family Aulophyllidae Dybowski, 1873 

Genus CORWENIA Smith and Ryder, 1926 emend. 

Oorwenia Smith and Ryder. 1926, Ann. Mag. Nat. History, v. 17, 

p. 149. 

Oorwenia Smith and Ryder. Hill, 1940, Paleontographical Soc. 

Mon., p. 100--101. 

Oorwenia Smith and Ryder. Hill, 1956, in Moore, R. C., ed., 

Treatise on invertebrate paleontology, Part F, Geol. Soc. 

America, p. F288. 

Oorwenia Smith and Ryder. Dobroljubova. 1958, Akad. Nauk. 

SSSR Paleont. Inst. Trudy, v. 70, p.ll4-117. 

Oorwenia Smith and Ryder. Groot, 1963, Leidse Geol. Meded., 

pt. 29, p. 66. 

Type species.-Lonsda.leia rugosa McCoy, 1849, 

Lower Carboniferous, upper Visean; Corwin, Wales. 

Dia.gnosis.-Phaceloid aulophylline corals with a 

radially or bilate~ally sym1netrical axial columella; 

septa thin or dilated in all quadrants; dissepitheca may 

be present; some forms have. lonsdaleoid dissepiments; 

tabularium with periaxial ~and axial series of tabellae, 

strongly arched distally and peripherally convex. 

(Modified in pa,rt from Groot, 1963, p. 66.) 

Corwenia jagoensis n. sp. 

Plate 1, figs. 1-6; plate 2, figs. 1-5; plate 3, figs. 1-4; plate 4, 

figs. 1-4 ; pia te 5, figs. 2-4 

11/ ate rial.-The Inaterial and specimens avaiJ,able for 

study are shown in the following tabulation. 

Stratigraphic section 

68A-4A __________ _ 68A-5 ____________ _ 68A-5 ____________ _ 68A-5 ____________ _ 68A-5 ____________ _ 

63B-808 __________ _ 

68A-L ___________ _ 

68A-4A __________ _ 68A-4A __________ _ 68A-5 ____________ _ 68A-5 ____________ _ 68A-5 ____________ _ 

600-201 __________ _ 

Stratigraphic section 

USNM catalog No. 

161034 Holotype ____ _ 160533 Paratype ____ _ 160534 _____ do ______ _ 160535 _____ do ______ _ 160536 _____ do ______ _ 160537 _____ do ______ _ 

160538 _____ do ______ _ 161035 _____ do ______ _ 

161036 _____ do ______ _ 161037 _____ do ______ _ 161038 _____ do ______ _ 161039 _____ do ______ _ 

161040 _____ do ______ _ 

Corallum fragment (em) 

8X lOX 10 

12X 15X20 

8X lOX 11 

15X24X26 

lOX 12X20 

5X 6X 9 

6X 12X 13 

5X 9X 14 

6X 7X 15 

15X 19X20 

6X 7X 12 

lOX 14X 14 

9X 12X 15 

Transverse thin 

sections (2"X3") 

Longitudinal thin 

sections (2"X3") 

Number of Number of Number of Number of 

thin sections corallites thin sections corallites 

68A-4A __________ 2 20 3 5 68A-5 ___________ 1 4 2 6 68A-5 ___________ 1 23 2 8 68A-5 ___________ 2 4 1 2 

68A-5 ___________ 1 4 1 1 

63B-808 _________ 1 3 2 4 

68A-L __________ 2 5 1 3 

68A-4A _________ 1 1 1 1 

68A -4a __________ 1 11 1 4 

68A-5 ___________ 3 23 1 2 

68A-5 ___________ 2 21 2 5 

68A-5 ___________ 2 34 ] 2 

600-201 _________ 3 16 1 4 

Description.--The holotype, USNM 161034, is a fasciculate corallum (fig. 8). Corallites arise by offsets. A 

corallum is approximately 40-45 em in dia1neter. In 

transverse section eorallites range from 5 to 18 mm in 

diameter, and long, slightly sinuous major septa range 

from 20 to 32. The Inajor septa are continuous through 

the dissepimentarium and are 100-125 microns thick at 

their junction with the corallite wall. Within the tabulariunl the major septa a.re dilated and are 250-350 

microns thick at the tabularium wall, tapering gradually to their distal ends. The axial side of the tahularimn wall and the dissepiments are thickened by a 

150- to 300-micron-thick stereozone (pl. 1, figs. 2, 4). In 

transverse section the minor septa are short, penetr31te 

only a short distance past the dissepimentarium into the 

tabularium,.and are commonly discontinuous within the 

dissepimentarium. The counter septa, and in some specimens, the cardinal septa are continuous with the 

columella; the other major septa are genera.Iy withdrawn from the axial region. The ~olumeHa is cle~arly 

formed by the dilation of the axial end of the eounter 

septum and ranges from 1-4 mm long and 100-200 
SYSTEMATIC PALEONTOLOGY 11 

20 

19 EXPLANATION 

Stratigraphic USNM 

18 Symbol section Catalog No. Type 

8 68A-4A 161034 Holotype 

17 $ 68A-4A 161035 Paratype 

ii!J 60C-201 161040 Do. 

16 68A-5 161039 Do. 

15 

14 

13 

12 

11 

10 

"' 9 0:: 

UJ 

..... 

UJ 

~ 8 ...J 

=' :::;; 

z 7 

o::' 

UJ 6 ..... 

UJ 

:::;; 

<t 5 0 

UJ 

~ 

...J 4 ...J 

<t 

0:: 

0 

u 15 

14 EXPLANATION 

Strat igraphic USNM 

13 Symbol section Catalog No. 

12 0 68A-5 161039 

+ 68A-5 161038 

11 68A-5 161037 

* 68A-5 160533 

10 X X 68A·4·A 161036 

9 

8 

7 

6 

5 

4 

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 

NUMBER OF MAJOR SEPTA 

FIGURE 8.-Corallite diameter and number of major septa in Corwenia jagoensis n. sp. 
12 PENNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

microns thick. In transverse thin section the columella 

is commonly surrounded by a spiderweb pattern that is 

formed in the plane of the thin section which cuts the 

upturned axial surface of the tabulae and their septa.! 

ridges (pl. 1, fig. 3). 

\Vi thin coralla the smaller corallites (diameter 8.0 

mm or less, 21- 24 major septa) resemble the larger 

corallites except for their narrower dissepimentarium 

that is composed of two rows of dissepiments and their 

minor septa that are discontinuous within the dissepimentarium. 

A coralli{e 18 mm in diameter in transverse thin section (pl. 1, fig. 6) has a dissepimentarium 2.5- 3.5 mm 

wire formed by 4-6 rows of globose dissepiments. The 

peripheral stereozone is present on the axial side of the 

last ring of dissepiments facing the tabularium. The 

tabulae, generally incomplete, show a tendency to develop an inner and outer series of tabulae (pl. 1, fig. 5). 

The columella is persistent and slightly sinuous. The 

tabulae near the dissepirnentarium slope up from the 

horizontal 20°-30°, whereas those near the columella 

may slope ;)0°- 60° from the horizontal. 

The microstructure of the corallum is generally well 

preser·ved (pl. 1, figs. 1-4). The corallite wall, 100- 125 

microns thick, is formed by dense fibrous calcite with 

the fibers oriented normal to the exterior wall. The wall 

can be divided into two parts-an outer dark-gray band, 

30-40 microns thick, and an inner lighter colored band, 

70- 95 microns thick. The septa appear to be composed 

of a slightly different textural type of calcite. The junction of the septa and the corallite wall is distinctly 

marked by an embayment of the septa into the corallite 

wall. The microstructure of the corallite wall and the 

septra is similar to and conforms to the type described 

by Kato ( 1963, fig. 17C) as lamellar. In transverse section, the septa in the dissepimentarium have a dark central band 10- 15 microns wide, and at either side fibrous 

calcite is at nearly right angles to the central band (pl. 

1, fig. 1). The septal stereozone in the tabularium appears to be a simple thickening of the fibrous calcite 

forming the outer layer of the major septa. The stereozone on the dissepiments is also fibrous calcite (Don pl. 

1, fig. 4), but where it abuts against the septal stereozone, 

a sharp line of demarcation can be seen (pl. 1, figs. 1-2). 

Petrographic studies dearly show that the columella 

is an extension of the counter septum and that the 

tabulae are fused to it. In longitudinal thin sections, the 

dissepiments and tabulae are 20- 35 microns thick and 

are composed of dense calcite crystals which are fiber 

shaped to rhomb shaped and 4 microns in size or smaller 

(pl. 1, fig. 4). The sequence of void filling within., the 

corallum began with an ,initial deposition on all internal surfaces of rhombs of sparry calcite 10-15 microns 

in size followed by deposition of interlocking rhombs 

0.1- 3 mm in size. 

Specimens USNM 161035, 161037, 161040, 160535, and 

160536 typify the large corallites of this species and are 

very similar to the holotype in morphological details. 

Specimens USNM 160533 and 160539 typify the 

smaller corallites of the species with fewer major septa. 

Thin sections of USNM 160539 show tha;t the corallites 

range in diameter from slightly more than 4 mm to 10 

mm and have 19-23 major septa. Morphological features 

in general are similar to those of the holotype and are 

very similar to those of the smaller corallites in the 

corallum of the holotype, however, the major septa are 

slightly longer and the axial structures are better 

developed than in the holotype. 

Occurrence.-The holotype, USNM 161034, and the 

paratypes, USNM 161035 and 161036, were collected 250 

feet below the top of the East Sadlerochit Mountains 

section, 68A-4A-4B. Paratype USNM 160537 was collected by Stanley F. Schindler, Shell Oil Co., in 1963, in 

a measured section about 1.25 miles west of section 68A4A-4B. at a stratigraphic level in the Wahoo Limestone 

165 feet below the contact with the Sadlerochit Formation. Other paratypes were collected at the following levels below the top of Egaksrak River section 

68A-5 (fig. 9): USNM 161039 at 230 feet, USNM 

161037 and 161038 at 270 feet, USNM 160533 and 160534 

at 285 feet, and USNM 160535 and 160536 at 450 feet. 

Paratype USNM 160538 was collected about 70 feet 

below the top of the Ikiakpuk Creek section 68A - 1. 

Paratype USNM 161040 was collected by Stanley F. 

Schindler, Shell Oil Co., in 1960, in a measured section 

near Salisbury Mountain, long 146°19' W., lat 69°14' N. 

The specimen was collected in the "T ahoo Limestone 5 

FIGURE 9.-Large cora1lum of Convenia. jagoensis n. sp. showing 

shape of colony and corallite growth. Scale shown by pencil 

in lower right. Corallum occurs in a coral-rich bed of the 

Wahoo Limestone al.Jout 450 feet below the top of the Egaksrak 

River section 68A-5; see figure 1 for stratigraphic location. 
SYSTEMATIC PALE<ONTOLOGY 13 

feet below the contact with the Sadlerochit Formation 

in limestone beds which contain a microfossil fauna of 

Atoka age. 

C 01'Wenia jagoensis n. sp. is found within the Wahoo 

Limestone in a biostratigraphie zone of Atoka age. Assoeiated microfossils are Jlfillerel1a spp., Endothyra of the 

group E. nwsquensis Reitlinger, Lipine77a sp., N eoarchaediscus grandis (Reitlinger), Climaca1nmina ef. C. 

moellel'i Reitlinger, D t'inella sp. 1 Eoschubel'fella sp., 

Globivalvu1ina sensu stricto, and Pseudostaffella sp. 

Remadcs.-The fasciculate rugose eorals of the 

Wahoo Limestone present problems of classification at 

both the. generic. and specific. leYels and appear to represent a transitional fonn between the Mississippian 

genus Corwenia Smith and Ryder and the Pennian 

genus H eritschioides Yabe. 

A conservative concept is used in this study to define 

the genus Corwenia. Groot's (1963, p. 66) observations 

on the type speeies of Oorwenia rugosa (MeCoy) are: 

"That the septa may be dilated at the margin of the 

tabularium in all quadrants is shown in figure 12 of 

Smith, 1916, pl. 21, a section of the ephebic. stage of a 

specimen of Oonvenia rugosa from the type-locality. A 

section of an earlier stage of the same coralhun * * * 

shows likewise a slight dilation of the septa and the 

presenee of a dissepitheca. ~' These two eharaeteristies, 

the development of stereozones on the septa and dissepitheca, are the pri1nary reasons why Yabe (1950) set 

up the genus lleritschioides, whose type speeies is Oorwenia columbica (Smith, 1935) \vhich is from the 

Pennsylvanian or Permian beds of British Columbia. 

Minato and l(a.to (1965, p. 31), in their redescription of 

the genus 0 orzcenirt as contrasted to the genera of their 

new fa1nily Durha1ninidae whieh ineludes H eritschioides, state "the axial structure of Oorzvenla is quite 

eharaeteristic, in \vhich septal lamellae are firmly united 

with the prolong,ation of axial ends of major septa. 

Further, cardinal and counter septa are also directly 

united with Inedium plate. Aecordingly, the axial strueture in 0m'1.venia is quite regulady constructed by 

radially arranged septal lamellae and a few concentrically arranged axial tabulae." The fascieulate eorals 

from the \:Yahoo Limestone have well-developed 

eohunellae fonned by the cardinal and counter septa 

·and have dilated n1ajor septa in the tabularium and 

\vell-developed dissepitheea (pl. 11 figs. 1---!). The \Vahoo 

Limestone specimens differ from the type species of 

HeJ·ibschioides, H. columbica (Smith), in having less 

well-defined inner and outer series of tabulae. Furthermore, the tabulae in the \Vahoo Limestone speeimens are relatiYely widely spaced in contrast to the 

elosely spaced inner tabellae of H eritschioides colwnbica. 

Speeimens of 0 orwenia jagoensis n. sp. from the 

Atolm age beds of the vV ahoo Limestone are believed to 

represent an unstable forn1 because they show considerable structural variation in the eorallites of a corallnm 

and of different coralla. One is strongly tempted to define two species of Oorwenia. from the vVahoo Limestone 

material, based on eorallite size and nmnber of septa, 

clevelop1nent of the eolumellae, and length of 1najor 

septa, but even within one colony wide gradations exist 

in corallite diameter, number of septa, and n1orphology. 

The eontrast behveen corallum end members of the 

population is great, as can be seen by comparing specimens LTSN~f 160534 (pl. 3, fig. 1) and USNM 161040 

(pl. 4, fig. 4 ; pl. 5, figs. 2---!). 

Specimens USNl\I 160534 and 161039, with their 

smaller corallite diameters, longer major septa, and less 

steeply inclined inner tabellae, resemble more closely 

the generic. characteristics of 0 orwenia. 

Specimen USNl\I 161040 appea.rs to be the most highly 

evolved speei1nen of Oorwenia in the eollection. It has 

more elosely spaeed inner tabellae and also welldeveloped septal and dissepithecal stereozones. Thus, of 

all the speeimens, it shows the elosest relationship to 

the genus H erit8chioides Yabe. 

The holotype, LTSNM 161034, reveals in its larger 

corallites most. of the eharacteristics of specimen 

USNl\1: 161040 and in its smaller eorallites most of the 

eharaeteristics of speeimen lTSNM 160534. The material 

now available for study indicates that all the ;:;pecimens 

of Oor1Denia from the Wahoo Limestone probably represent one speeies. Further collecting of large numbers 

of Oo·J'wenia from the \Yahoo Limestone 1nay permit 

the differentiation of one or more species. 

None of the deseribed species of corals from the 

Cordilleran region of North Ameriea are closely related 

Ol' similal~ to Oorwen ia jagoen.rsis n. sp. vVaagenophyllwn columbicwn Smith (19351 p. 38) frmn the· Permian 

or Pennsylvanian of British Columbia differs in a significant number of eharaeteristies; its eorallites have a 

diameter of 10-17 mm, 25 major sept•a and long minor 

septa, and upward-sloping tabellae. Tlw tabellae are 

more densely paeked together than in 0. jagoensis and 

form a well-developed and wider clisiophy lloid 

strueture. 

Oorwenia sym,rnetr2~ca (Dobroljubova) from the 

upper ~1oseovian of the Moscow and Donetz basins of 

the lTSSR (Fomiehev, 1953, p. 396) and Groot's (1963, 

p. 69) speci1nens frmn similar age beds of Palencia, 

Spain, have diameters of 5-9 mn1 with 16-20 major 

septa, long minor septa, and weakly dilated n1ajor septa 

near the Inargin of the tabularium. C. synunetrica is 

dose 1norphologically to 0. jagoenfSi:s n. sp. The latter 

species differs primarily in having shorter n1inor septa 
14 PENNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

and a colonial habit which forms coralla composed of 

closely spaced corallites (fig. 9). The Eurasian species, 

in contrast, is, frmn the descriptions given by Dobroljubova (1937, p. 58) and Fomichev (1953, p. 394), a 

solitary or weakly cmnpound form. 

Oorwenia longisepta (Fomichev, 1953, p. 396) is a 

species frmn the upper Moscovian of the Donetz basin, 

1TSSR. Groot (1963, p. 69) describes her specimens, 

fron1 similar age beds in Palencia, Spain, as having 24-

26 major septa in a corallite diameter of 9 mm. It differs 

from 0. jagoernsis in having longer 1ninor septa and 

major septa which generally reach the axial region. 

Name.-The specific name is derived from the Jago 

River, which heads at a glacier in the Romanzof Mountains and flows northward into the Arctic Ocean. 

Family Lons,daleiidae Chapman, 1893 

Genus LITHOSTROTIONELLA Yabe and Hayasaka, 1915 

Lithostrotionella Yabe and Hayasaka, 1915, Geol. Soc. Tokyo 

Jour., v. 22, p. 94. 

Lithostrotionella Yabe and Hayasaka. Hayasaka, 1936, Taihoku 

Imp. Univ., Formosa, v.13, no. 5, p. 47-58. 

Petalaxis Edwards and Haime. Fomichev (part), 1953, Vses. 

Nauchno-Issled. Geol. Inst. Trudy, p. 449--452. 

Lithostrotionella Yabe and Hayasaka. Hill, 1956, in Moore, 

R. C., ed., Treatise on invertebrate paleontology, Part F, 

Geol. Soc. America, p. F306-307. 

Type species.-LithostJ•otionella wnicu/ln Yabe and 

Hayasaka, 1915, Perinian, Chihsia Limestone,·Yun-nan, 

South China. 

Diagnosis.-Cerioid corallum, prismatic corallites, 

columella a persistent vertical lath frequently continuous with counter and cardinal septa. Lonsdaleoid dissepiinents. All major septa intermittently reach the 

wall along the tops of the dissepi1nents. Minor septa 

short. Tabulae frequently complete, conical. (Summarized from Y abe and Hayasaka, 1915, p. 94). 

Lithostrotionella wahooensis n. sp. 

Plate 5, fig. 1; plate 6, figs. 1-5; plate 7, figs. 1-3 

1Jf ateriaZ.-Fraginents of e,ight coralla are available 

for study. The coralla are, by Lisburne Group coral 

standards, small, generally less than 25 em in diameter. 

Most colonies are preserved in a pale-gray to a grayishred-purple chalcedony; however, parts of some coralla 

have some corallites preserved in calcite. All the specimens were studied in 2- by 3-inch thin sections and polished slabs. The material available for study is shown 

in the following tabulation. 

Stratigraphic section 

69A-1 ____________ _ 69A-1 ____________ _ 69A-1 ____________ _ 69A-1 ____________ _ 68A-3 ____________ _ 69A-2 ____________ _ 69A-2 ____________ _ 69A-2 ____________ _ 

USNM catalog No. 

160528 Holotype ____ _ 160525 Paratype ____ _ 160526 _____ do ______ _ 160527 _____ do ______ _ 160529 _____ do ______ _ 

160530 _____ do ______ _ 

160531 

160532 

Corallum 

fragment (em) 

12X 12X 18 

4X 4X 5 

5X 7X 7 

6X 7X 9 

7X 14X 15 

4X 6X 7 

4X lOX 11 

6X 7X 8 

Transverse thin sections Longitudinal thin sections 

(2"X3") (2"X3") 

Stratigraphic section ---------- ----------- Number of Number of Number of Number of 

thin sections corallites thin sections corallites 

69A-l ___________ 1 17 1 5 69A-l ___________ 1 7 2 10 

69A-l_ __________ 2 16 2 5 69A-l ___________ 1 8 1 7 

68A-3 ___________ 1 32 1 4 

69A-2 ___________ 1 12 1 7 

69A-2 ___________ 1 14 1 6 69A-2 ___________ 1 15 1 5 

Description.-The holotype, USNM 160528, is a cerioid corallmn, about 28 em in diameter and 16 em in 

depth, that is shaped like a flattened cone. 

The corallites, 5-8 111m in diameter, have 19-23 long 

sinuous major septa (fig. 10) that are slightly dilated in 

the tabularium. Most of the major septa are continuous 

throughout the dissepimentarium; generally no more 

than one or two major septa are discontinuous in any 

corallite. The cardinal and counter septa are commonly 

continuous with the elongate, thin columella. Serial sections indicate that the septa are high ridges on the 

upper surfaces of the tabulae. In transverse section, the 

upward-arched tabulae and the major septa produce a 

spiderweb patteril around the columella (pl. 7, fig. 1). 

The minor septa are short, generally le,ss than 1 mm 

long. They are discontinuous in the dissepimentarium 

and comn1only occur as a series of short ridges on the 

axial sides of the dissepiment walls. The major and 

minor septa near their junctions with the corallite wall 

are 80-110 microns thick. The microstructure of the 

holotype has been obscured by the growth of calcite 

crystals. The individual calcite crystals which form the 

corallite walls and septa are now 8-15' microns in size. 

Petrographic studies suggest the microstructure was 

fibrous. The major septa on the axial side of the tahularimn wall are 80-150 ·microns thick and taper towards 

their distal ends. The columella typically is 100-150 
SYSTEMATIC PALEONTOLOGY 15 

11 

EXPLANATION 

10 Stratigraphic USNM 

Symbol section Catalog No. Type 

0 69A-1 160525 Paratype 

9 X 69A-1 160527 Do. 

69A-1 160528 Holotype 

+ 68A-3 160529 Paratype 

8 

+ 7 

6 

5 

(J) 

a: 

w 4 1-

w 

~ _J 

:::! 

~ 3 

~ 

ci 

w 2 1-

w 11 ~ 

<( EXPLANATION 

0 Stratigraphic USNM 

w Symbol section Catalog No. ~ 10 _J 

69A-2 160530 _J 

<( 

+ 69A-2 160531 a: 

0 

u 9 0 69A-2 160532 

8 

7 

6 

5 

4 

3 

2 

11 12 13 14 15 16 17 18 19 20 27 

NUMBER OF MAJOR SEPTA 

FIGURE 10.-Corallite diameter and number of major septa in Lithostrotionella wahooensis n. sp. 
16 PIDNNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

microns thick, has a central band 10 1nicrons thick, and 

is eomposed of dense fibrous calcite. The wall between 

two corallites, 150-200 microns thick, has a dark~ dense 

central band 10-20 1nicrons thick and appears to be 

forn1ed of fibrous calcite (pl. 7, figs. 1, 2). The internal 

voids of the corallum are filled by two phases of crystal growth. The first phase lined all interior surfaees 

with 25- to 50-micron-size crystals of sparry calcite; the 

second phase filled the voids with chalcedony. 

Longitudinal sections show the dissepimentariun1 to 

be formed by three to four rows of globose dissepiments 0.5 111n1 wide to 1.5 nun long. The tabulae are commonly incmnplete; the outer series slope upwards at 

angles of 30°-40° frmn the horizontal, the inner series 

slope upwards at angles of 45°-60° frmn the horizontal. 

Petrographic studies of the cohunella indicate that it is 

for1ned by the axial ends of the 1najor septa. The tabulae and dissepiments in seetion are 15-20 n1icrons thick 

and are con1posed of dark, dense, 8- to 10-Inicron-size 

crystals of calcite. 

Paratypes lTSNM 160525 and 160527 were collected 

3 feet stratigraphically above the holotype and are very 

similar in 1norphological details and preservation to the 

holotype (fig. 10). 

The three speci1nens fron1 the Wahoo Limestone of 

the Shublik Mountains, USNM 161030, 161031, and 

161032, are preserved in chert nodules. In general these 

coralla display a thicker somewhat n1ore massive columellae, longer septa, and three to five more 1najor septa 

per corallite (fig. 10) than the holotype. 

Paratype USNM 160529 (pl. 6, fig. 5) is similar to the 

holotype except that the columellae are less well developed and the tabulae display a tendency to\vards being 

cmnplete and not as strongly arched upwards to meet 

the columellae. The specimen is preserved in a chert 

nodule. 

Oconrrence.-The holotype USNM 160528 and paratypes lTSNM 160525, 160526, and 160527 are from the 

upper part of the "'Vest Sadlerochit Mountains section 

69A-1, "'V ahoo Limestone (figs. 1, 2). Para type USN~1 

160529 is from measured section 68A-3 near the 1niddle 

of the Sadlerochit Mountains (fig. 15), and l_TSNM 

161030-161032 are from within an undescribed section 

(69A-2) at the west end of the Shublik Mountains 

(fig. 16). 

Lithostrotionella walwoensis n. sp. has been found 

only in the upper part of the "'Vahoo Limestone, in 

grain-supported high-energy packstones and grainstone that are associated with bedded oolites. Microfossils found with Litlwsfl'otionella wahooensis n. sp. 

are Endothyra of the group E. 1nosquensis Reitlinger~ 

lllillo'ella spp., Neoarchaedi8CU8 grand is (Reitlinger), 

GlimacanMnina cf. C. moelleri Reitlingei\ Eo8chubertella sp., P8eudmstaffella sp., and Globit•alt•ulina sp. 

These fossils are characteristie of microfauna! assenlblage zone 21, Atoka age, Middle Pennsylvanian. 

Rmnarks.-L£thostrot-ionella wahooemw is differentiated from the various species of Meramec and early 

Chester (Late Mississippian) age Li.thostrotionella 

found in the underlying Meramec age Alapah Limestone and Kayak ( ? ) Shale by the development of a 

n1ore complex tabularimn with a tendency toward inner 

and outer zones of tabulae. 

Groot (1963, p. 85-86, pl. 18, fig. 2) describes Lithostrotionella orboen&i& Groot fron1 the upper Moscovian 

Orbo Limestone of Palencia, Spain. L. 01'boensi8 has 

some characteristics in common with L. 1lJahooen8i8 but 

differs in having two to three fewer major septa per 

corallite, better developed and larger lonsdaleoid dissepiinents and, in the tabularium, longer minor septa. 

Also in transverse section the tabularium is not as well 

differentiated into zones of inner and outer tabulae as in 

the Alaskan species. 

Petalawi8 1nohikana Fmnichev (1953, p. 459-462) 

fron1 the upper Moscovian of the Donetz. Basin, USSR, 

is similar in transverse section to L. wa.hooen&is but differs primarily in having somewhat smaller corallites 

with only 13 or 14 major septa and complete tabulae. 

Narn,e.-The specific name is derived frmn the Wahoo 

Li1nestone. 

GRAPHIC REGISTRY OF STRATIGRAPHIC 

SECTIONS AND FOSSIL LOCALITIES 

This report is primarily concerned with the Pennsylvanian carbonates and corals of the Lisburne Group. 

The Lisburne Group also includes in this area the Late 

Mississippian Alapah Limestone, whieh is not discussed 

in this report. Sections 68A-1, 69A-1, and 68A-4A-4B 

from the Wahoo Limestone, which are described and 

graphically illustrated (fig. 1), are underlain by considerable thicknesses of Mississippian carbonates. The 

1nicrofossil zonation and lithologies of these older earbonates are deseribed by Armstrong, :Ma1net, and Dutro 

(1970). Section 68A-3 in the central Sadlerochit Mountains is structurally complex and is not described in this 

report. (See Armstrong and others, 1970, fig. 4.) The 

vVest Shublik Mountains section, 69A-2, which has 

yielded a nmnber of specimens of Lithostrotionella 

'Wa1woensis n. sp., is badly faulted and has not previously been described; detailed stratigraphic description 

or stratigraphic illustrations of it are not given in this 

report. 

Reiser, Dutro, Brosge, Annstrong, and Detterman's 

(1970) geologie maps of the Sadlerochit Mountains 

give. detailed ( 1 : 63,360 seale) geologic settings for seetions 69A-1~ 68A-4A-4B, and 68A-3. Figures 11 

through 16 are detailed graphic locations of the measured stratigraphic seetions of this report. 
GRAPHIC REGISTRY OF STRATIGRAPHIC SECTIONS AND FOSSIL LOCALITIES 

TlS w 

I' 

N 

0:: 

4 3 2 1 

9 10 11 12 

16 15 14 13 

T700 tt 

68A-1lo 

21 22 23 24 

28 27 26 25 w 

I' 

N 

0:: TlS 

FIGURE 11.-Ikiakpuk River section 68A-1. 

T3N 

11 12 7 8 

14 13 18 17 

.,.600 ft 

23 69A-~ 

24 0 19 20 

26 25 30 29 

35 36 31 32 w w 

LD lO N N 

0:: 0:: T3N 

FIGURE 12.-West Sadlerochit Mountains section, 

69A-1. See figure 2 for a photograph of the outcrop 

and fossil locality. 

35 36 31 32 

T4N 

T3N 

2 1 6 5 

68A-4B )... 

'( 0 

!:.875ft 68A~4A 

11 12 7 0 8 

~prox1mate locat1on 

Shell 011638-801 

0 

14 13 18 17 

23 24 19 20 w w 0 

(¥) ;:; 0:: 0:: 

FIGURE 13.-East Sadlerochit Mountains sections, 

68A-4A-4B, and approximate location of Shell Oil 

Co. section 63B-801 from which paratype, USNM 

160537, Oorwenia jagoensis, was collected. 

36 31 32 33 

T3N 

T2N 

1 6 5 4 

12 7 8 9 

13 18 

268A-5 

17 16 1250 ft 

24 19 20 21 w w 

00 CJl (¥) (¥) 

0:: 0:: 

FIGURE 14.-Egaksrak River section 68A-5. See figure 4 for an outcrop photograph. 

17 
18 PBNNSYLVANIAN CARBONATES, PALEOECOLOGY, AND RUGOSE CORALS, ARCTIC ALASKA 

T3N 

11 

14 

23 

26 

35 

12 7 

13 18 

ot 

/68A-3 

19 

f I. Location of L. wahooensis 1200 t""' coral collect1ons 

25 

36 w w 

I' co N N 

0:: 0:: 

30 

31 

8 

17 

20 

29 

32 

T3N 

FIGURE 15.-Central Sadlerochit Mountains section 

68A-3. This section is not discussed in detail in 

this report. 

T2N 

w 

8 9 10 11 LD 

N 

0:: 

17 16 15 14 

20 21 22 23 

69A-~ ~Location of 

L. wahooensis 

coral collect1ons 

29 28 27 26 

w 

LD 

32 33 34 35 N 

0:: 

T2N 

FIGURE 16.-West Shublik Mountains section 69A-2. 

This section is not discussed in detail in this 

report. 

SELECTED REFERENCES 

Armstrong, A. K., 1967, Biostratigraphy and carbonate facies 

of the Mississippian Arroyo Penasco Formation, northcentral New Mexico: New Mexico Bur. ~fines and Mineral 

Resources Mem. 20, 80 p., 10 pls., 45 figs. 

----1970, Carbonate facies and the lithostrotionid corals of 

the ~1ississippian Kogruk Formation, DeLong :\fountains, 

northwestern Alaska: U.S. Geol. Survey Prof. Paper 664, 

38 p., 14 pls., 37 figs. 

Armstrong, A. K., MacKevett, E. M., Jr., and Silberling, N. J., 

1969, The Chitistone and Nizina Limestones of part of the 

southern 'Vrangell Mountains, Alaska-A preliminary report stressing carbonate petrography and depositional environments, in Geological Survey Research 1969: U.S. Geol. 

Survey Prof. Paper 650-D, v. D49-D62, 9 figs. 

Armstrong, A. K., and l\famet, B. L., 1970, Biostratigraphy and 

dolomite porosity trends of the Lisburne Group, in Adkison 

W. L., and Brosge, M. M., eds., Proceedings of the geological seminar on the North Slope of Alaska: Los Angeles, 

Pacific Sec., Am. Assoc. Petroleum Geologists, p. N1-N16, 12 

figs. 

Armstrong, A. K., Mamet, B. L., and Dutro, J. T., Jr., 1970, 

Foraminiferal zonation and carbonate facies of Carboniferous (Mississippian and Pennsylvanian) Lisburne Group, 

central and eastern Brooks Range, Arctic Alaska : Am. 

Assoc. Petroleum Geologists Bull., v. 54, no. 5, p. 687-698, 4 

figs. 

---1971, Hsburne Group, Cape Lewis-Niak Creek, northwestern Alaska, in Geological Survey research 1971 : U.S. 

Geol. Survey Prof. Paper, 750-B, p. B23-B34. 

Ball, M. :\1., 1967, Carbonate sand bodies of Florida and the 

Bahamas: Jour. Sed. Petrology, v. 37, no. 2, p. 55~91, 

figs. 1-40. 

Ball, M. ~I., Shinn, E. A., and Stockman, K. W., 1967, The geo~ 

logic effects of Hurricane Donna in south Florida : Jour. 

Geology, v. 75, no. 5, p. 583-597, 14 pls., 2 figs. 

Bo·wsher, A. L., and Dutro, J. T., Jr., 1957, The Paleozoic section in the Shainin Lake area, central Brooks Range, 

Alaska: U.S. Geol. Survey Prof. Paper 303-A, 39 p., 6 pis., 

4 figs. 

Brosge, ,V. P., Dutro, J. T., Jr., Mangus, M. D., and Reiser, 

H. N., 1962, Paleozoic sequence in eastern Brooks Range, 

Alaska: Am. Assoc. Petroleum Geologists Bull., v. 46, no. 12, 

p. 217 4-2198. 

Cloud, P. E., Jr., 1955, Physical limits of glauconite formation: 

Am. Assoc. Petroleum Geologists Bull., v. 39, no. 4, p. 482-

492. 

Coogan, A. H., 1969, Recent and ancient carbonate cyclic sequences, in Elam, J. G., and Chuber, S., eds., Symposium on 

cyclic sedimentation in the Permian Basin (1967) : West 

Texas Geol. Soc. Pub. 69-56, p. 5-27, 6 figs. 

Detterman, R. L., 1970, Sedime-ntary history of the Sadlerochit 

and Shublik Formations in northeastern Alaska, in Adkison, 
SIDLECTED REF1ERENCES 19 

W. I.~., and Brosge, M. M., eds., Proceedings of the geologic 

seminar on the north slope of Alaska : Los Angeles, Pacific 

Sec. Am. Assoc. Petroleum Geologists, p. 01-013, 9 figs. 

Dobroljubova, T. A., 1937, Simple corals of the Myatshkova and 

Podolsk horizons of the Middle Carboniferous of the Mos:-

cow basin : Paleozool. Inst. Trudy, v. 7, no. 3, 92 p. [in 

Russian]. 

Dunham, R. J., 1962, Classification of carbonate rocks according to deposition texture, in Classification of carbonate 

rocks-a symposium : Am. Assoc. Petroleum Geologists 

Mem. 1, p. 108-121. 

Fischer, A. G., 1964, The Lofer cyclothems of the Alpine Triassic, in Merriam, D. F., Symposium on cyclic sedimentation: 

Kansas Geol. Survey Bull., v. 169, no. 1, p. 107-149. 

Fomichev, V. D., 1953, Coral Rugosa and stratigraphy of the 

Middle and Upper Carboniferous and Permian deposits of 

the Donetz basin: Vses. Nauchno-lssled. Geol. Inst. Trudy, 

622 p., 44 pls. [in Russian]. 

Fri.edman, G. M., 1959, Identification of carbonate minerals by 

staining methods: Jour. Sed. Petrology, v. 29, no. 1, p. 87-97. 

Groot, G. E., de, 1963, Rugose corals from the Carboniferous of 

northern Palencia (Spain) : Leidse Geol. Meded., pt. 29; 123 

p., 26 pis., 39 figs. 

Hill, Dorothy, 1938-1941, The Carboniferous rugose corals of 

Scotland : Palaeontogra.phical Soc. Mon. [London], 1938, pt. 

1, p. 1-78 (v. 91), 2 figs., 2 pis.; 1939, pt. 2, p. 79-114 (v. 92), 

3 pis. ; 1940, pt. 3, p. 115-204 ( v. 94) ; 1941, pt. 4, p. 205-213 

(v. 95). 

---1956, Rugosa, in Moore, R. C., ed., Trerttise on invertebrate 

paleontology, Part F., Coelenterata: Geol. Soc. America and 

Kansas Univ. Press, p. F233-F324. 

Kato, Makoto, 1963, Fine skeletal structures in rugosa: Hokkaido Univ. Fac. Sci. Jour., ser. 4, v. 11, no. 4, p. 571-630, 

3 pis., 19 text figs .. 

Lochman-Balk, Christina, 1957, Paleoecology of the Cambrian 

in Montana and Wyoming, chap. 8 of Ladd, H. S., ed., Paleoecology: Geol. Soc. America Mem. 67, p. 117-162, 1 pl., 7 

figs. 

Logan, B. W., Rezak, R., and Ginsburg, R. N., 1964, Classifica.-

tion and environmental significance of algal stromatolites: 

Jour. Geology, v. 72, no. 1, p. 68-83, 5 figs. 

Minato, Masao, and Kato, Makoto, 1965, Durhaminidae (Tetracoral) : Hokkaido Univ. Fac. Sci. Jour., ser. 4, v. 8, no. 1, 86 

p., 5 pls., 24 figs. 

Murray, R. C., and Lucia, F. J., 1967, Cause and control of dolomite distribution by rock selectivity: Geol. Soc. America 

Bull., v. 78, p. 21-35. 

Reiser, H. N., Dutro, J. T., Jr., Brosge, W. P., Armstrong, A. K., 

and Detterman, R. L., 1970, Progress map, geology of the 

Sadlerochit and Shublik Mountains: U.S. Geol. Survey 

open-file map, scale 1 :63,360. 

Roehl, P. 0., 1967, Stony Mounta.in (Ordovician) and Interlake 

(Silurian) facies analogs of Recent low-energy marine and 

subaerial carbonates, Bahamas·: Am. Assoc. Petroleum 

Geologists Bull., v. 51, no. 10, p. 1979-2032. 

Shinn, E. A., 1968a, Practical significance of birdseye structures 

in carbonate rocks: Jour. Sed. Petrology, v. 38, no. 1, p. 215-

223, figs. 1-13. 

---1968b, Burrowing in recent lime sediments of Florida and 

the Bahamas: Jour. Paleontology, v. 42, no. 4, p. 879-894, 

pls. 109-112, figs. 1-17. 

Shinn, E. A., Ginsburg, R. N., and Lloyd, R. M., 1965, Recent 

supratidal dolomite from Andros Island, Bahamas, in Dolomitization and limestone diagenesis-A symposium: Soc. 

Econ. Paleontologists and Mineralogists Spec. Pub. 13, 

p.112-123. 

Smith, Stanley, 1916, The genus Lonsdaleia and Dib'Ltnophyllum 

rugosum (McCoy) : Geol. Soc. London Quart. Jour., v. 71, 

p. 218-272, pl. 21, figs. 3-16. 

---1935, Two anthracolithic corals from British Columbia 

and related species from the Tethys: Jour. Paleontology, 

v.9,no.l,p.30-42,pls.8,9. 

Smith, Stanley, and Ryder, T. A., 1926, The genus Corwenia 

gen. nov.: Annals and Mag. Nat. History, v. 17, no. 9, p. 

149-159, pls. 7, 8. 

Wilson, J. L., 1967a, Cyclic and reciprocal sedimentation in Virgilian strata of southern New Mexico: Geol. Soc. America 

Bull., v. 78, no. 7, p. 805-817, 4 pls., 4 figs. 

---1967b, Carbonate-evaporite cycles in lower Duperow 

Formation of Williston basin: Canaman Petroleum Geology, 

v. 15, no. 3, p. 230-312, 22 pls., 14 figs. 

---1969, Microfacies and sedimentary structures in "deeper 

water" lime mudstones, in Friedman, G. M., ed., Depositional 

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Paleontologists and Mineralogists Spec. Pub. 14, p. 4-19. 

'Vilson, J. I.~., Madrid-Solis, A., and Malpica-Cruz, R., 1967, 

Microfacies of Pennsylvanian and Wolfcampian strata in 

southwestern U.S.A. and Chihuahua, Mexico, in New Mexico 

Geol. Soc. Guidebook 20th Field Conf. : p. 80-90, 4 pls., 3 figs. 

Yabe, H., 1950, Permian corals resembling Waagenophyllum and 

Corwenia: Japan Acad. Proc., v. 26, no. 2-5, p. 74-79. 

Yabe, H., and Hayasaka, Ichiro, 1915, Palaeozoic corals from 

Japan, Korea, and China: Geol. Soc. Tokyo Jour., v. 22, no. 

264, p. 93-109. 

Page 

Alapah Limestone ________________________ 3, 4, 10,16 

Algae, calcareous_____________________________ 5, 9 

Arctic Ocean_________________________________ 14 

Aulophyllidae______ ____ ___ ___ _ ____ _ ___ ____ _ __ 10 

Bahama Banks_______________________________ g 

Biostratigraphy ___ -----______________________ 3 

Brachiopods__________________________________ 6, 9 

British Columbia_____________________________ 13 

Bryozoans _____________ ----------- ___________ _ 

Bryozoan-crinoid wackestones and packstones, 

Wahoo Limestone_________________ 4, 5 

Bryozoan-e,chinoderm packstones, Wahoo 

Limestone.__ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4 

Bryozoan-echinoderm packstones and wackestones, Alapah Limestone _______ _ 

Bryozoan-echinoderm wackestones and packstones, Wahoo Lime,stone_________ 5, 7 

Carbonate depositional megacycle____________ 6, 7 

Carbonate stratigraphy_______________________ 3 

Cherty dolomite, Alapah Limestone _________ _ 

Chihsia Limestone,___________________________ 14 

Climacammina moellerL _____________________ 3, 13,16 

columbica, Corwenia__ __ __ __ _ _ _ _ ___ _ _ _ __ _ _ _ _ _ __ 13 

Heritschioides_ _ _ _ __ _ ___ _ _ __ _ _ _ _ _ _ __ _ _ _ __ _ _ 13 

columbicum, Waagcnophyllum_________________ 13 

Corwenia_ _ _ _ _ __ _ _ __ _ __ _ _ _ __ _ __ _ _ __ _ _ _ _ _ _ _ _ _ _ _ 10 

columbica___ _ ___ _ _ _ _ _ _ _ __ _ _ _ _ _ _ __ _ _ _ _ _ _ __ _ 13 

jagoensis _____ ____________________________ 3, 9, 10 

longisepta__ __ __ __ _ _ _ _ _ ___ _ ___ _ _ ___ _ _ _ _ _ _ _ _ 14 

rugosa____________________________________ 13 

symmetrica_____ _ _ __ _ _ _ __ _ __ _ _ ___ _ _ __ _ _ _ _ _ _ 3,13 

DeLong Mountains___________________________ 10 

Donetz Basin, U.S.S.R __________________ 3,13,14,16 

Durhaminidae_____ __ __ _ _ _ _ _ _ __ _ _ __ _ _ __ _ _ __ _ _ _ 13 

Dvinella sp _________________ ------------------- 13 

East Sadlerochit Mountain section ___________ 5, 6,12 

\Vahoo Limestone ____ -------------------- 4 

Echinoderm-bryozoan packstone s-w aek estones_ _ _ __ _ _ __ _ _ __ _ _ __ _ _ _ _ _ __ _ ___ 8 

Echinoderms_________________________________ 9 

Egaksrak River section _______________________ 8,12 

Wahoo Limeston~------------------------- 5 Endothyra __________________________________ 3, 13,16 

mosquensis ___ ___________________________ 3, 13,16 

Environments of de,position___________________ 6 

Eoschubertella sp ____________________________ 3, 13,16 

INDEX 

[Italic page numbers indicate major references] 

Foraminifera ________________________________ _ 

Fossil localities, registry _____________________ _ 

Fasulinella sp ________________________________ _ 

Fusulinids ___________________________________ _ 

Page 

5, 9 

16 

3 

Glauconite___________________________________ 5, 7 

Glauconite formation_________________________ 7 

Globivalvulina sp ____________________________ 3, 13,16 

grandis, Neoarchaediscus _____________________ 3, 13,16 

Graphic registry of stratigraphic sections and 

fossil localities.___________________ 16 

Groot, G. E., cited _____________________ 10, 13, 14,16 

Heritschioides_ _ ___ __ __ _ ___ _ ____ ___ _____ ____ ___ 13 

columbica ___ ___________ • _ ____ ___ _ _ ___ _ ___ _ 13 

lkiakpuk Creek _____________________________ _ 

Ikiakpuk Creek section ______________________ 5, 6,12 

Alapah Lime,stone________________________ 3 

Introduction _________________________________ _ 

Ja~o River___________________________________ 14 

jagoensis, Corwenia __________________________ 3, 9, 10 

Kato, Makoto, quoted________________________ 13 

Kayak(?) Shale_______________________________ 6, 16 

Kogruk Formation___________________________ 10 

Lipinella sp ___ ------------------------------- 3,13 

Lisburne Group __________________________ 3, 7, 10,16 

biostratigraphic zones____________________ 3 

Lithology, Alapah Limestone. ________________ _ 

Wahoo Limestone._---------------------- 4, 5, 6 Lithostrotionella__ __ __ _ __ _ _ ____ _ __ __ __ __ __ __ ___ 14 

orbocnsis___ __ _ ___ _ _ __ _ _ ____ _ ___ __ _ _ _ ___ ___ 3,16 

·unicum____ _____ ___________ ___ ____________ 14 

wahoocnsis ____ ___________________________ 3, 9,14 

Longisepta, Corwenia ___ _ ---------------------

Lonsdaleiidae. ________________ ----- _ ---------

Lonsdaleia rugosa _____________________ ----_---

14 

14 

10 

Mamet, B. L., rited__________________________ 3 

Millerella sp ________________________________ 3, 13,16 

Minato, Masao, quote,d_______________________ 13 

moelleri, Climacammina _____________________ 3, 13,16 

mohikana, Petalaxis__ _ _ ___ ___ _ _ _ _ _ ____ ____ ___ _ 3,16 

mosquensis, Endothyra_ --------------------- 3, 13,16 

Neoarchaediscns grand is _____________________ 3, 13,16 

0 

Page 

Ooids_________________________________________ 5, 7 

Orbo Lime,stone ___________________________ • _ _ 16 

orboensis, Lithostrotionella________ ____ _ ___ ____ _ 3,16 

Osagia sp _______________ . __________ -------- ___ 5, 8 

Palencia, Spain.-------------------------- 13, 14,16 

Pelletoidal-bioclastic-grainstones and packstones, Alapah Limestone _______ _ 

Petalaxis_ _ __ ___ ___ _ ___ ____ _ ____ ____ ___ _ ___ _ __ 14 

mohikana_________________________ ________ 3,16 

Previous work and acknowledgments. _ _ _ _ _ _ _ 3 

Profusulinella sp ______ ------------------------ 3 Pseudostajfella sp ___________________________ 3, 13,16 

Romanzof Mountains _______ . _______________ . 14 

rugosa, Corwenia _____ _____________________ . __ _ 13 

Lonsdale Ia. _____________ . _. ____ -___ -_ --- __ 10 

Rugose corals, adaptation_------------------- 10 

environments ________ .--------.----.------ 9 

Sadlerochit Formation________________________ 4,6 

Echooka Member ____ -------------------- 6 

Sadlerochit Mountains. _________________ 3, 5, 6, 7,16 

Schindler, Stanley F., cited___________________ 12 

Selected refe,rences ________________ ------------ 18 

Shublik Mountains. __________________________ 5,16 

Stratigraphic sections, registry------- ____ ---- 16 

symmetrica, Coru·enia _________________________ 3,13 

Systematic paleontology _____ ----------------- 10 

unicum, Lithostrotionella______________________ 14 

JVaagenophyllum columbicum__________________ 13 

Wachsmuth Limestone .. ______ --------------- 3 

Wahoo Lake__________________________________ 3 

wahoo Limestone _________________ 3, 4, 7, 9, 12, 13,16 

colonial coral assemblage ____________ - ___ - 9 

coral paleoecology _______________ --------- 9 

dolomites _________________ --------------- 8 

oolite marker beds _______________________ _ 

oolitic grainstone ______________ ---_------- 5, 8 

type section______________________________ 3 

wahooensis, Lithostrotionella __________________ 3, 9,14 

We,st Sadlerochit Mountain section ____________ 6,16 

Alapah Limestone ___________ -------------

Wahoo Limestone_-----------------------

West Shublik Mountains section _____________ _ 

3 

4 

16 

Wilson, James L., quoted_____________________ 8 

Yun-nan, South China_______________________ 14 

21 

U.S. GOVERNMENT PRINTING OFFICE: 1973 0- 467-564 

PLATES 1-8 

[Contact photographs of the plates in this report are available, at cost, from the U.S. Geological Survey Library, 

Federal Center, Denver, Colo. 8022·5] 
PLATE 1 

FIGURES 1-6. Corwenia jagoensis n. sp. USNM 161034, holotype. 250 feet below the top of 

East Sadlerochit Mountains section 68A-4A-4B, Wahoo Limestone, 

Atoka age. 

1-3. Transverse thin sections, X 25. 1, Arrows point to the well-developed 

dissepitheca and dilated septa. 2, Illustrates the differing microstructure of the septa and corallite wall, the dilated septa, and 

dissepitheca. 3, View of the axial region showing lath shape and 

microstructure of the columella (C) which is continuous with cardinal and counter septa, septal ridges (S) on upper surfaces of tabulae, 

and aulophylloid axial structure. 

4. Longitudinal thin section, X 25. View of corallite wall microstructure, 

dissepimentarium, and (D) junction of dissepitheca and tabellae . 

. 5-6. 5, Longitudinal thin section, X 3; replacement by chalcedony 

obscured lower part of corallite and some of the dissei)imentarium. 

6, Transverse thin section, X 3. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 74 7 PLATE I 

2 

4 

3 
PLATE 2 

FIGURES 1- 5. Corwenia jagoensis n. sp. 

1- 3, 5. 1-3, Longitudinal thin sections, X 3. 5, Transverse thin section, 

X a, holotype, USNM 161034; 250 feet below the top of the 

East Sadlerochit Mountain section 68A-4A-4B, Wahoo 

Limestone. 

4. Longitudinal thin section, X 3, paratype, USNM 161038; 270 feet 

below the top of the Egaksrak River ~ection 58A-5, Wahoo Limestone. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 PLATE 2 

CORWENIA JAGOENSIS n. sp. 
PLATE 3 

FIGunr:s 1-4. Corweniajagoensis n. sp. 

1. Tran~v se thin section, X 3, holotype, USNM 161034; 250 feet below 

the top of the East Sadlerochit Mountain section 68A-4A, Wahoo 

Limestone. 

2- 4. 2, Longitudinal thin section, X 3. 3, 4, Transverse thin sections, X 3, 

paratype, USNM 161038; 270 feet below the top of the Egaksrak 

River section GSA-5, Wahoo Limestone. 
2 

CORWENIA JAGOENSIS n. sp . 
PLATE 4 

FIGURES 1-4. Corwenia jagoensis n. sp. 

1. Transverse t hi n section, X 3, para type, USNM 160537; 150 feet 

below the contact of the Wahoo Limestone and Sadlerochit Formation. One and one-fourth mile west of section 68A- 4A. 

2, 3. Transverse thin sections, X 3, paratype, USNM 161039; 230 feet 

below the top of the Egahrak River section 68A-5. Wahoo Limestone. 

4. Transverse thin section, X 3, paratype, USNM 161040, near Salisbury Mountain, Wahoo Limestone. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 PLATE 4 

CORWENIA JAGOENSIS n. sp. 
PLATE 5 

FI:>URE 1. Litho;trotionella wahooensis n. sp. 

1. Transverse thin section, X 3, para type, USNM 160527; 50 feet from the 

top of th e Wc;;t Sadlerochit Mountains section 69A-1, Wahoo Limestone. 

2-4. Corwenia jagoensis n . ;;p. 

2. Longitudinal thin section, X 3; 3, 4, Transverse thin sections, X 3, para type, 

USNM 161040; near Salisbury Mountain, Wahoo Limestone. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 PLATE 5 

1 2 

·--"'"""""';.:=,IJ•,.,..,-~...:-rc"/~~IJf"""' 3 4 

LITHOSTROTIONELLA WAHOOENSTS n. sp. and CORWENTA JAGOENSTS n. sp. 
PLATE 6 

·FIGURES 1-5. Lithostrotionella wahooensis n . sp. 

1-3. 1, Transverse thin section, X 3; 2,3, Longitudinal thin sections, X 3, 

holotype, USNM 160528; 48 feet below the top of the West Sadlerochit Mountains section 69A-1, Wahoo Limestone. 

4. Transverse thin section, X 3, paratype, USNM 160530; Wahoo Limestone, West Shublik Mountain section 69A- 2. 

D . Transverse thin section, X 3, para type, USNM 160529; upper 75 

feet of the Wahoo Limestone, Sadlerochit Mountains section 68A-3. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 74 7 PLATE 6 

2 

3 

LITHOSTROTIONELLA WAHOOENSIS n. sp .. 
PLATE 7 

FIGURES 1-3. Lithostrotionella wahooensis n. sp. 

1-2. Transverse thin sections, X 25. 1, Axial region illustrating microstructure of columella which is continuous with 

the sinuous cardinal and counter septa. 2, Microstructure of the corallitc wall, with its dark central band, 

and of the sinuous major septa and discontinuous minor septa. The structures of the corallum are preserved 

as calcite, the internal voids of the corallum are filled by clear, colorless, transparent chalcedony. Holotype, 

USNM 160528; 48 feet below the top of the West Sadlerochit Mountain section 69A-l. 

3. Transverse thin section, X 25; corallum is preserved within a chert nodule. The microstructure of the corallites 

is preserved by a red jasper chalcedony, whereas the internal voids are filled with a clear chalcedony. Paratype, USNM 160529; upper 75 feet of the Wahoo Limestone, Sadlerochit Mountain section 68A-3. 

4-5. Section 69A-1, West Sadlerochit Mountains, Wahoo Limestone. 

4. Pelletoid to rounded micritic lithoclasts, bryozoan grainstone. Note the fine abraded bioclastic inclusion within 

the micritic lithoclasts. X 25; 65 feet from top of section. 

5. Crinoidal-bryozoan-algal wackestone and packstone. Bioclastic fragments arc finely abraded and broken; 

texture of rock suggests extensive burrowing. X 25; 150 feet from top of section. 

6-8. Section 68A-4A-4B, East Sadlerochit Mountains, Wahoo Limestone. 

6. Ooid foraminiferal grainstone. The centers of the ooids arc Foraminifera, broken and rounded fragments of 

echinoderms, bryozoans, and small micritic lithoclasts. X 25; 290 feet from top of section. 

7. Ooid-micropelletoid grainstone. Rounded and winnowed fragments of bryozoans, echinoderms, ostracodes, 

and micritic pellets with, typically, a single oolitic coating; X 25; 490 feet from top of section. 

8. Bryozoan-echinoderm-algal packstone. Poorly sorted fossil fragments with micrite filling the voids between 

the bioclasts. X 25; 570 feet from top of section. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 PLATE 7 
PLATE 8 

FIGURES 1-6. Section 68A-5, Egaksrak River, Wahoo Limestone. 

1. Pelletoid-bryozoan-echinoderm grainstone. Fossil fragments and pellets are rounded and winnowed; one layer of 

oolitic coating on pellets and on some rounded bioclasts. X 25, 150 feet from top of section. 

2. Oolitic grainstone. Large ooids, 0.6-0.7 mm in diameter, have numerous and thick oolitic layers. Ooids generally 

have fossil fragments for their centers and show evidence of algal borings. Associated with the ooids are abundant Osagia sp. X 25, 600 feet from top of section. 

3. Pellctoid-bryozoan-echinoderm grainstone. Rounded and winnowed bioclasts, with small Foraminifera, Globivalvulina sp. X 25, 430 feet from top of section. 

4. Bryozoan-echinoderm-foraminiferal lithoclast packstone and grainstone. Large rounded fossil fragment, micrite 

lithoclasts, and varying amo unts of micrite pore and void filling. X 25, 750 feet from top of section. 

5. Bryozoan packstone. Large bryozoan fragments in micrite. Large fossil fragments parallel to bedding suggest 

deposition in a noncurrent environment. X 25, 830 feet from top of section. 

6. Echinoderm-gastropod-foraminiferal-bryozoan packstone and gra instone. Rich, diversified fauna; broken and 

rounded, but poorly sorted, bioclasts and lime mud, suggesting extensive burrow and weak currents. X 25, 

1,130 feet from top. 

7- 8. Section 68A-1, Ikiakpuk section, Wahoo Limestone. 

7. Tectonically stressed oolitic grainstone. Fossil fragments and oolites have been elongated by tectonic str ess and 

solution; Ooids are ellipsoids. X 25, 20 feet from top of section. 

8. Tectonically stressed bryozoan-echinoderm packstone. Note the elongation and grain growth of the crinoid 

ossicles. Echinoderm ossicles are particularly prone to alteration and elongation due to tectonic stress. X 25, 

95 feet from top of section. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 747 PLATE 8 

5 6 

7 8 

Photomicrographs of carbonate rock types in sections 68A-5, 68A-1.