U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

Cc

MIDDLEBURG FAULT

SUFFIELD FAULT

I
SCIENTIFIC INVESTIGATIONS MAP 3172)

(SHEET 1 OF 2),

Explanatory pamphlet accompanies map!
i}

GEOLOGIC CROSS SECTION C-C' THROUGH THE APPALACHIAN BASIN FROM ERIE COUNTY, NORTH-CENTRAL OHIO, TO THE VALLEY AND RIDGE PROVINCE, BEDFORD COUNTY, SOUTH-CENTRAL PENNSYLVANIA

\
\
\
\
i}
\
\
| iJ © | s '
ig £18 ;
cle
6 IS ‘Bl § i
2|5 Bend in Section 5|3 Bend in Section
Olg gis '
12 S15
1S Sic \
| NW NE | SE |
\
\
MILES '
0 15 20 25 30 35 40 55 60 65 75 85 105 110 115 120 125 130 !
L 1 1 1 1 1 1 in 1 in 1 1 1 1 n 1 1 1 1 n 1 1 in 1 n 1 1 1 1 ni 1 1 1 1 in 1 1 1 1 1 1 1 n 1 1 1 1 n 1 1 1 1 ni 1 1 1 1 1 n 1 1 1 1 1 1 1 1 1 4 1 1 1 in 1 1 1 1 1 in 1 1 1 1 1 1 1 1 1 1 1 it
4 \
Formation tops \
Formation tops Formation tops Formation tops Formation tops (surface to Chagrin Shale)
3000 (surface to Rose Run sandstone) (surface to Rose Run sandstone) (surface to Rose Run sandstone) {surface to Rose Run sandstone) derived from the '
q derived from the derived from the derived from the derived from the Atlas Resources Inc. '
q East Ohio Gas Co. Tristate Producing Co. Belco Petroleum Corp. Occidental Petrolem Corp. No. 1 McMichael \
q No. 1-2431 Frederick No. 1 Sanor ‘API 37-007-20089 \
2500 API 34-151-21123 API 34-029-20620 API 34-029-20618 API 34-029-20668 Beaver Co., Pa. |
4 2 3 4 Stark Co., Ohio Columbiana Co., Ohio 5 Columbiana Co., Ohio Columbiana Co., Ohio 6 7 (in Harper and Laughrey, 1987) ;
4 ast Ohio Gas iser Oi jelden & Blake Co., Limited Partnership janagement Contro! jumble Oi t. Joe Petroleum Corp. \
East Ohio G: Wiser Oil Belden & Blake Co., Limited P: hip #9 M it Control Humble Oil St. Joe Petroleum C
2000 —| jo. orn }0.1-A F.L. Smith Estate Jo. 1~: . Westfal jo. 3 Frank Murray lo. 1S. Minesinger lo. 1 Richard J. Ashcrot |
| No. 1A &A Bi No.1-A FL. Smith Estat No. 1-381 B. Westfall No. 3 Frank Mi No. 1S. Minesi No. 1 Richard J. Ashcroft
ml Lorain Co., Ohio Medina Co., Ohio Stark Co., Ohio Columbiana Co., Ohio Hancock Co., W. Va. Beaver Co., Pa. \
\
1 \
1500 Sun Oil Company Sharon Conglomerate Sharon Conglomerate Middle Mississippian Hl
° , i 4 Li .d Middl Upper Freeport Conemaugh Grou Upper Freeport d
=] No. 1 Krysik-Wakefield of the Pottsville Group of the Pottsville Group Allegheny Group kinanning aM beds I iP Conemaugh Group Lower and Middle Conemaugh Group unconformity Monongahela Group. Hl
4 Erie Co., Ohio ee Se, TEE 0 Kittanning coal beds |
4 legheny ir q
1000 — FEET Pottsville Group Group r c Cc @ Conemaugh Group Lowerand  "esetbag |
4 " i | be Middle Kit ir
a 5. ‘Cuyahoga Formation emt ett z Sunbury Shel . Pottsville Group Cc Cc 2 i allegheny oT epee !
q Berea Sandstone eee Berea Sandstone Cuyahoga Formation = OT Fer0u c q
Tiivao i rd Shi ——— 2 unnamed sandstone’ Guinea onan iP Cc c—,
Lick Bed leveland Member RET SSRaG unbury Shale uyahoga Formation Pottsville Group c.
Chagrit 2S
grin Shale Leesa Chagrin Shale | s000 . . Lemay aco Berea Sandstone Cussewago Sandstone: =svahoga juaw sandstone Mauch Chunk Formation i
“ Canes Sandstone)
= eee eee a Da Bf fe  _ _ _ Bete and Cussewago Sandstones (undivided) yee 1000 Sag {Cuyahoga Se) j
Tou
(000 ans aa 7 [a Squaw sandstone
oS S82890 Sandetones una
gNIged) 35 0s
‘West Falls Fm. odk y Harper and Laughn
cane nthteeen merernrermevayre ee ET a a . Chagrin Shale . we Se
Bass Islands Dolomit arin) po . Venango |
Group ass Islands Dolomite Mahantango Formation L-2000 am == on a Group |
iT TT ~~ ~~ 1-200 [ we :
Lower Silurian MMU ETS cy gain ~~ ax
cal £arbonates and shal MO ry CRD aw ~ ~ —
4 es (undivideg) ou amy a ~ ~ !
4 Rochester Shale Lr ry ry Tota ~ ~ ek \
1500 Lockport Dolor: FT jc re LOT) Dunkirk Shale Member of ~~ a Chagrin aw ~~)
=. lomite the Perrysburg Formation a Shale \
into samaes 3000 [3000 ~ ~
stone Cohonie F000 | aw !
ot Head Shain 2A WS Java Formation +3000 a |
ET ECOO COT |
ey Angola Shale Member \
i
Cincinnat; jonyea Formatior {
ati group Mahantango F, . {
“ieee 90 Formation |
IF 4000;
a Genesee Format si Dunkirk Shale Member of |
he Perrysburg Formation \
100 az \
vee — — in
3500 Kerbel Formation z [Knox Botomaes Tully Limestone’
ml 5 anes
cal " = g = ! = West Falls
y sh 5 aes = Salina Group vestiballs {
7 On Zone a \
| Le Ind Ki
4000 ap Sik sa \
cal 4,591 Gai 08 = Sandstone (undivided)
q Maryville eae lurk a
J Limestone = eR ole sndSholslunded ri ao a
4500 | Mount Simon Sandstoné (RST Shale = = Ockport Dolomite ee = Group
7 ; > << : Clint Roel TI
t-6000 22" sandstone hester Shaig MW
5000 : . Sant 16000 wall
q 7 ° Medin, A r
4 Hinge zone(?) Sandstone (ung: mi 2S
y . Vided) Salina Group
4 Ans . aa Lower Siluri bi
00 Ea = = - crete neatena®
4 1S on > = Ochester
7 =57000 - = = = = 17000 Shale Rose ay
6000 1D 7,040 Nolichucky Shale equivalent = = — 00 e Hil Formation
EXPLANATION . . = a Cincinnat; ca
os a up
6500 SEDIMENTARY ROCKS LITHOLOGIC MODIFIERS OTHER SYMBOLS = =
4 Dominant Lithology (Used in conjunction with Dominant Lithology) _ 000 Se
3000 I Contact—Dashed where inferred; queried where uncertain 7D 7,961 |_go00
4 Conglomeratic sandstone Sandy ' |
7 1 Arbitrary lateral boundary of rock-stratigraphic unit a
| ' =
7500 | Sandstone maT | Silty Unconformity—Queried where uncertain Hinge zone(?)
4 ~~... | Sandstone and siltstone —— | Argillaceous, gray and (or) green —>— Normal fault—Dashed where inferred; arrow shows relative movement = 9000 R
q = eedsviy
8000 : ile
Red sandstone and red siltstone 7] Argillaceous, red (red R shown where dominant lithology of 2“ Thnust or bedding plane faults of the Alleghanian orogeny = ekmantown dol hale
— . — 101
q gray and (or) green shale contains minor red shale beds) Ose Mite
= ——— Normal fault with later episodes of reverse motion (inversion)—Dashed where inferred un Sands; |
yy Red shale =] Coal bearing = to i
0 200 009 am f
- 1 + . y + 7 L unnamed sandstone Hl
Black shale / Anhydritic Gamma-ray log curve in American Petroleum Institute (API) units—Log units and scales vary, 10,000 Nolichucky Shale equivalent (St. Peter Sandstone equivalent’ |
see appendix B in explanatory pamphlet . 0, —
Ma
"Wille; Ro: =
Gray and (or) green shale AAA e Li se Rui Beekmantown.
y and (or) gre Cherty Total depth TD 10,242 2, MRSto, = " Sandstone Gaul oF
FEET Hi Mou, TD 10,387 =
= linge zone(? nt Sj ceo =
Dy Limestone _._| Calcareous Estimated depth to basement from Shumaker (1996) 2000 g (?) Simon § Beekmbntown
= Copper Ridge Dolomite ets
Dolomite — Dolomitic Estimated depth to basement from Berg and others (1980) 1750 4 iat ee ~
Halite Fault from Shumaker (1996) and Kulander and Ryder (2005) 1500 >) ue = Gatesburg “Pper Sandy —
5 ; mei
4 . Formation be,
1250 0 085 a
IGNEOUS ROCKS Fault from Scanlin and Engelder (2003) ee = Zoey !
Bentonite bed 1000 4 bo
22304 Granite and (or) gneiss + . a \
—c Coal, greater than 1 foot thick LoeSh (on) gm 750 : welaes
500 4 Formation ~
250 5 00
10 MILES 1
0 4, 11 1 5
Allegh I
Rome trough Allegheny 0 10 15 KILOMETERS isda
front and 1
9 Valley and Ridge Vertical exaggeration approximately 16X 1 Sandsion
ee province
North-Central Ohio Northeastern Ohio Northernmost West Virginia-
- 5 Western Pennsylvania
(Drill holes 1-2) (Drill holes 3-5) . .
A ‘onal E North Amer (Drill holes 6-7) Southwestern Pennsylvania] South-Central Pennsylvania
e nternationa uropean | North American . North American] _ Yorn American (Drill holes 8-9) (Drill holes 9-11)
9° leon System P , International Stage sequences modified 3
(Ma) Series Series Stage from Sloss (1988)
a 251.0 5 Changhsingian 8
4 Lopingian | a g , . .
4 260.4 | ping 3 Sn Wuchiapingian [>| Pittsburgh-Washington cross-strike
13,500 —] , . 3 Capitanian Capitanian g structural discontinuity
+ Guadalupian | 3 - - - c 3
4 2706 S = Wordian to Roadian Wordian to Roadian o =
a ° ra Kungurian € Approximate location of the Coshocton zone of Culotta and others (1990) a
14,000 + = c=
4 2 5 Leonardian Artinskian Absaroka & 8
Cisuralian | 2 3
as] 5 &
Sakmarian
7 Wolfcampian
4 299.0 a - Asselian
_ aan 5 |,Autunian _ “tian Gzhelian = |i
15,000 4 > Stephanian ” Missa ezhelian Conemaugh Group Conemaugh Group Conemaugh Group 2 (2
q 306.5 4 § | Ste naan oinesian : t Conemaugh Group & tS
4 3117 4 2 Westphalian Atokan Moscovian yea C———Aleshory Group c = Allegheny Group [Allegheny Group > 3 |
15,500 S$ Morrowan Bashkirian Ops Pottsville Group] Pottsville Group Pottsville Group Pottsville Group \ 5 $
q 318.1 aL Namuri sharon Conglomerate Lower Pennsylvanian unconformity S_* ts
J 2 emurian Toran Serpukhovian Sacre eres auch Chunk Fxmaton wg i ingore Mob 2 i
q 2  eneenenenpremenemeenans een ne Wiymps Gap 5
326.4 5 ® o 2]
16,000 fle ae a \ tongue ot eon | SE
5 a Loyalhanna Formation’ ‘Loyalhanna Formation Formation) 5 e
q a|? Meramecian Visean a 2
q < | 2
16,500 —| &|3 Kaskaskia II Middle Mississippian (Sub-Loyalhanna Formation) unconformity os _
4 345.3 — @ Osagean ° r
4 S k we ‘Burgoon Sandstone (Big Injun sandstone) Burgoon Sandstone Burgoon Sandstone 5 iE
17,000 ; ; ournaisian cuyahog: Sree, Shenango Formation [Squaw sandstone, TShenango Formation EF stenango Formation & ] -
4 Kinderhookian Suhr sto | Sunbury Shalo. Cuyahoga Formation sere Sopasione |[Cavahogs Formation Sunbury Shale _Cuvahoue Gov] yar PETAL Teae agr) Cuyahoga Group _,OMa¥9, [etvatooe Gru Formation 7 %
q 359.2 Bedford Shale. _Berea Sandstone, — = a = = : sf = Munroe zone ot saan Eastern l (8
7 2 Fd Shale Cussewago Sandstone| Bere and Cussewago es a ——— —— i
Chautauquan Famennian 5 ce EES cieallcian > | SESSA eer SP = — granite re Ce SOC
3 ¢ Chagrin Shale Elk Group x Scherr Formation ~ \ q provinee 3 ‘ :
é 6 ro
18.000 —| Kaskaskial — “Gisitinay Shae luppe Java Formation Java Formation pocalllerme . . s
. 4 c F : West Fall “Angola Shale Member ‘West Falls jola Shale Member Brallier Formation S
| o BS Senecan Fasnian Middle to Upper Devonian unconformity — Formation ones Formation c
q 2 wi Hamilton ‘Sonyea Formatiot’ ae Format Harrell Formation a
18,500 | 3853 9 2 g Tae Givatian Einosione rou _ — 2 ———= zs oe < Hinge zone ;
3,500 *| eaten jamiton ton Tully Lin fahantango Formation 2
7 8| 8 3 eon] en a A [Para fubetmetone—_Mineraraorematen | "gro” [ul eone-—_ Naverangjgmaion Fer ubyunasene—_Natanrgo Fema & i
a i} Southwood Hetian S
a 375] 2 2 & Savi Emsian |
c © s a i Columb Detroit Rive
E & 5 Deer Park Pragian Columbus gre asi Blane, . ;
5 | Helderberg? Lochkovian & ;
416.0 -| d Keyser Formation !
aes unname Keyser Limestone 5
418.7 4 Cayugan g Tippecanoe II Zaina Grays Taina Grown’ Sata Gyan c 2
c Ludfordian to Gorstian it °
222.9 | g ° Lockport Dolomite Lockport Dolomite Carte eamD & LI i
= = . . =
we2—-| 3 ; ils Homerian to Sheinwoodian Shak Flochester Shale SSNSTETERIE R R R 5 7 |
7) Niagaran® | 3 Telychian Lower Silurian carbonates and shales (undivided) Lower Siturian carbonates and shales (undivided! ~ Fra [Rose Hil Formation oso Hil Formation [Rose Hil Formation 7 ao |:
8 —_— Shales &
437 Aeronian to Rhuddanian ee “Clinton”ss, Cabot Head Sh, and Medina ss (un "Clit ss, Cabot Head Sh, Medina Group. [Tuscarora Formation Cees Mane Tuscarora Formation comanes Merbar \
7 aa _ 7 Tiana Dacosaton Shale, Cherokee unconformity scarore Juste wension 30 Hl
Ashgillian Cincinnatian 5 ae —— i |
Katian® — Utica Shale. Cincinnati group Cincinnati group __-Utica Shale Utica Shale__Reedsville Shale “Antes Shale “Antes Shalex Reedsville Shale ~Bald Eagle Formation “Antes Shale Fesdsvile Shale “Bald Ears Formation 7 ;
i field- [Kiet :
Caradocian Mohawkian ian Rocklandian® Tippecanoe | 5 '
4 S Sandbian® [Twin] Blackriveran® c '
q 460.9 4 3 Danvimni — Ne cma Cee go
21,500 4 S anvirnian Whiterockian Darriwilian [Weis ree formation 1 “Wells GracCionnaton  Sannamed sandstone} aS) 3 !
q 6 Dapingian® Sandstone EE | 3 = !
cal 411.8 > z Arenigian Floian® ht 3 [|
vp 000 | fe) ian Knox unconformity neaeennstal SE expen | a
—] a Beekmantown| g
4 Ibexian . i é \
Tremadocian Tremadocian rose Run Beekmantown Beekmantown Dolomite Group rapa 3 '
sandstone ' . ' ; EXPLANATION
_| Rose Run Sandstone. ‘Mines Dolomite Member ‘Mines Dolomite Member. '
488.3 5 _ anamed Trempealeauan? 8 zone and Krysik sandstone (undivided) ———= SS upper sandy member a upper sandy member . ‘Axis of anticline—AA, Amity anticline; AFA, Arches Fork anticline; BA, Blackwat. \
5 g _. u - ‘Copper "Kno oan KSI TBST [Copper nex Dotomite || Gopre" Bron and Rn] “Fhember cm 0 ee Serre or TESCO g —t— Aris of anticline—AA, Amity anticline; AFA, Arches Fork anticline; BA, Blackwater
Furongian & Croixian? > _ ? anon Korbel Formation, Ridge dolomite Dolomite Notichucky Shale eauiv ge dolomite 1 Deere etc Fompton | lower sandy member ais fi Uinening_ rompt Ce eee s anticline; BMA, Briery Mountain anticline; BrA, Brownsville anticline; BSA, Burning
501.0 4 Paibian Sauk SS ——— SESS Mary us | _ Warrior Formation t [| Springs anticline; BTA, Broad Top anticline; BVA, Belle Vernon anticline; CRA, Chestnut
; ; Sandstone Nolichtucky Maryvite cogasan Sandstone Maryvite cogesane® HY Warrior Formation Warrior Formation c 2 Ridge anticline; DPA, Deer Park anticline; EA, Etam anticline; EMA, Evitts Mountain
a c Albertan’ unnamed ‘imestone imestone "Mount Simon Sandstone Potsdam Sandstone’ | } Pleasant Hill Formation| & 2 anticline; EVA, Elkins Valley anticline; FA, Fayette anticline; GA, Glady anticline; HA,
q 4 © - - S| Horton anticline; HiA, Hiram anticline; HuA, Hundred anticline; LHA, Laurel Hill
513.0 < Pleasant Fil 01 3; HIA, ; HUA, ; LHA,
23,500 > € = = Ca Fon To 5 Creek Mountain anticline; SD, Schellsburg dome of the Deer Park anticline; WMA, Wills '
o & Chilhowse Group fomstown Formation Hnowee Group (s) . Mountain anticline; WSA, Wolf Summit anticline '
4 3 i}
3
+ Waucoban? & Axis of syncline—BS, Bedford syncline; CVS, Clearville syncline; PS, Parkersburg syncline I
\
Axis of arch 1
\
542.0 Structural front—ASF, Allegheny structural front |
| Cross-strike structural discontinuity—CSD, Cambridge structural discontinuity; PWSD,
600 Pittsburgh-Washington structural discontinuity; TMUSD, Tyrone-Mt. Union. structural
discontinuity ;
°
4 700 | 8 Thrust fault—Sawteeth on upper plate. CPT, Cumberland Plateau thrust fault; PMT, Pine |
q fe) di ; Mountain thrust fault \
5 935 Ma potassium-argon age 860 Ma rubidium-strontium age 850 Ma potassium-argon age
3 of Grenville province rocks of Grenville province rocks of Grenville province rocks Normal fault—Bar and ball on relative downthrown side; dashed where inferred. BGFZ, 1
800 + £ (Lidiak and others, 1966) (Lidiak and others, 1966) (Lidiak and others, ie Bowling Green fault zone; IPCFZ, Irvine-Paint Creek fault zone H
° \
3 x x Strike-slip fault—Arrows show relative movement \
PENNSYLVANIA
900 Fault—Dashed where inferred. AF, Akron fault; HF, Highlandtown fault; MF, Middleburg ;
moe RRA RAC EAA R AAI RIAA RR RAR RR RRR RRO CORRES RAR RRR fouls SE, Sulfeld fouls STF, Smith Township [aut
Ko PPP POPP PT PPPOE POPP OPP POP POPP POPP BP OPT OP POPP Proterozoic basement rocks at surface \
7 1000) 2 SAARI ARISES RIAU KARAS RAIS EAN SSRIS AORN !
4 8 EASA SARA RAREST RASA) ANUSARA RA NURS URSA DURA SRA URANUS Interpreted seismic line (Kulander and Ryder, 2005)
27,000 4 ° RAIA AANCANSANTA IANS ANSANCANSANS ANS ARS ANSANSANSANSAW ANS ARSANSANSAN SANS ANS ACSANSANSANSANSAN ALS ARSANSANSAN SANS ALTARS ARSANSANSAND INC ANSARSANSAN SANS ANS AN SACS ANSANOANSALS 0 25 50 75 100 MILES A
4 AAA AAA A AIALIA RAOUL ALOU KALIL AL] ALA Aa AA AAA AAA ALALIATNS NIAAA AAAS Line of section (this report) 1
110-4 8 Hae reer eee ee eee eee ee ee TTC TEP coment rocks (matamorshie safe IPI ISIE I TOTO ISS
SIAC ANS ANS ANS ANANSA IOASSANS ANS ANS ANS ANS ANS ASA SSANSANSAN ANSANS BRYON SINC ANS ANS ANS AS SASSANSANSANSANSANSANS | NOANSANSANSANS ANS ANS ANS ANAL ANAS ASS
° Hace cee TTT and igneous) of the subsurface =!<-|svssn ssn bse sessed Sed ESS SP PSS SNe TP ° 6 00 180 KILOMETERS Line of section (Ryder and others, 2008) '
27,500 | a IOP TOOT extension of the Grenville Province! fr PO OPPO WEST VIRGINIA }
| 1,200 3 ETT PPT POTTS P TP OT TTP RAMEN 2d. MDCT, 1998) PTT TPT TTT PT EPP POT TTI Line of section (Ryder and others, 2009)
7 N ACOA ANSANSAN SANS ANSA NE ANOANT ANG AN SANS ANS ANS ANA NT ANSANSANS AN SANS AN SANS ANAS SANSANSANSANOANSANOAN SANSA SANS AN SANS AVANT ANS AN SANSANSANS [NSA NSANOANT ANA SANS AV SANS ANSANS ANG ANS
4 9 ELS ESS ESS ESS LSS ESS ESS ISS LSS ES ESS ETUC IS ES ES ISS US SSIS ISS US STS ISS US SES ISS ICS US ES ESS US US ESS ICS US PS SIS IRS US ESS SUS ESI ICS IS ESS IS IS SSIS Location of drill hole used to construct cross sections C-C', D-D', and E-E' '
g PPP IPP PT PPP PPP PPP PPP PPP PPP PP PPP POPP POTTY '
1,300 + ° SAAC AAS AN ANSANS AN SANS ANSA NE AN OANT ANA SANS AN SANS AN SANTANA SANS AN SANS AN SANS AN SAN SAN SAN SANSANOANS AN SAN SANSA SANS AN SANS AN SANTANA SANSANSANS [NOANS AN SANTANA SANS AV OANSANSANS ANS ANS U.S. Geological Survey corehole !
2 IPO OPPO PPP POPP OT
AANA ARORA RARARA AIA IOT SONORA ROAR OTe ORONO RORAI AR OIORORORARARORON DIOR OROMORO ROIS RanIOIe ROAR ARORA OR AION ORO \
S ESSENSE AGI NING ENG ISS GSE EPI LIEGE ABI OLE Kerr-MoGee No.1 Martin drill hole ;
® Kecini: |
1,400 $s ‘Heckel and Clayton (2006). Extent of West Virginia dome |
?Harland and others (1990). !
Ver Straeten and Brett (2006). |
4 1,500 — 4Brett and others (1995). Figure 1.—Map of Ohio, West Virginia, Pennsylvania, and adjoining States showing location of cross section C-C' and selected tectonic features. Tectonic and geologic features are from Hardeman (1966), Cardwell and others (1968), Gwinn (1970), Rodgers !
q 5Webby (1995). (1970), Janssens (1973), Wallace and de Witt (1975), Berg and others (1980), Milici (1980), Denison and others (1984), Kulander and Dean (1986), Virginia Division of Mineral Resources (1993), Drahovzal and Noger (1995), Shumaker (1996), Van Schmus ;
7 §International Commission on Stratigraphy (2009). and others (1996), Faill (1998), and Baranoski (2002). ;
29,500 1,600 | 7Follows Ryder and others (2009). \
q \
I Figure 2.—Correlation chart of Paleozoic rocks along cross section C-C' in Ohio, northernmost West Virginia, and Pennsylvania. Geologic time scale from Gradstein and others (2004) except as noted. Abbreviations are as follows: equiv, equivalent; Fm, Formation; Gp, Group; Ls, Limestone; Ma, million years (mega-annum); mbr, member; Sh, Shale; ss, sandstone.
30,000 1g gi vl gi ye a |
\
\
i}
\
\
\
\
\
i}
\
\

ZUSGS

science for a changing world

By

Robert T. Ryder, Michael H. Trippi, Christopher S. Swezey, Robert D. Crangle, Jr., Rebecca S. Hope, Elisabeth L. Rowan, and Erika E. Lentz

2012

Any use of trade, product, or firm names in this publication is for descriptive
purposes only and does not imply endorsement by the U.S. Government

For sale by U.S. Geological Survey, Information Services, Box 25286, Federal

Center, Denver, CO 80225; telephone 1-888-ASK-USGS

2D Printed on recycled paper

Hl
ISBN 978-1-4113-3277-5,

4 I

81411133, I

\
i}
9 I