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Kbd

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Kst

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30°

29°

28°

30°

29°

28°

106° 104°105° 103° 102° 101° 100°

104°105°106° 103° 102° 101° 100°

27°

27°

10 0 10 20 30 40 50 KILOMETERS

SCALE 1: 500 00010 0 10 20 30 40 MILES

DATA SERIES 170PLATE 3

Version 1.1

U.S. DEPARTMENT OF THE INTERIORU.S. GEOLOGICAL SURVEY

Southwest Quadrant

GEOLOGIC MAP OF TEXASCompiled by

Virgil E. Barnes1992

Prepared in cooperation with the

TEXAS BUREAU OF ECONOMIC GEOLOGY

MAP LOCATION

TEXAS

NORTHEASTQUADRANT

(Plate 1)

SOUTHEASTQUADRANT

(Plate 4)

NORTHWESTQUADRANT

(Plate 2)

SOUTHWEST QUADRANT

(Plate 3)

Lambert Conformal Conic projection

1927 North American Datum

Geologic map database of Texas by Stoeser, D.B., Shock, N.,Green, G.N., Dumonceaux, G.M., and Heran, W.D.

Any use of trade names is for descriptive purposes only anddoes not imply endorsement by the U.S. Government

GIS and PDF files are available online athttp://pubs.usgs.gov/ds/2005/170/

KfdKfd

PROVINCE NO. 2TRANS-PECOS TEXAS AND EAST BANK OF PECOS RIVER

PROVINCE NO. 1NORTH AND CENTRAL TEXAS INCLUDING PANHANDLE

PROVINCE NO. 2TERTIARY IGNEOUS AND VOLCANICLASTIC ROCKS, TRANS-PECOS TEXAS

PRESIDIO COUNTY EXCLUSIVE OF PRESIDIO COUNTY

EXPLANATION

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PROVINCE NO. 4WESTERN PART OF TRANS-PECOS TEXAS

PROVINCE NO. 3EASTERN PART OF TRANS-PECOS TEXAS AND HIGH PLAINS

PROVINCE NO. 6NORTH, CENTRAL, AND SOUTH TEXAS INCLUDING QUATERNARY

FOR ALL OF WEST TEXASPROVINCE NO. 5

EAST TEXAS AND GULF COAST TO RIO GRANDE

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Dewey Lake Redbeds

Rustler (Pru), and Salado and Castile Formations, undivided (Psc); gypsumof Rustler, Salado and Castile Formations, undivided (Prc); and Tessey

Limestone (Pts)

Mina Grande Formation

Bell Canyon (Pbc), Cherry Canyon (Pcc), and Brushy Canyon (Pbr),Formations; Bell Canyon, Cherry Canyon, and Brushy Canyon

Formations, undivided (Pbb); Carlsbad Group (Pcb); Capitan (Pc), Tansill (Pt),Yates (Py), Seven Rivers (Psr), Goat Seep (Pgs), Munn (Pm), and Word (Pw) Formations

Ross Mine (Pr), Cibolo (Pci),and Pinto Canyon (Ppc) Formations

Briggs (Pbg), Victorio Peak (Pvc), Cutoff (Pco), Bone Spring (Pbs),Cathedral Mountain (Pcm), and Wilkie Ranch (Pwi) Formations

Skinner Ranch and Hess Formations, undivided

Hueco Limestone

Lenox Hills and Neal Ranch Formations, undivided

Magdalena Formation

Alta Formation

Cieneguita Formation

Gaptank Formation

Haymond Formation

Dimple Formation

Paleozoic rocks, undivided (Pal); Tesnus Formation (�Mt); Helms Shale,Rancheria Formation, Las Cruces Limestone, Percha Shale, and

Canutillo Formations, undivided (MDh); Fusselman (Sf), and Montoya (Om),Dolomites; Missisippian, Devonian, and Ordovician rocks, undivided, (MDO);

Caballos Novaculite and Maravillas Chert, undivided, (MDc); Ordovician rocks, undivided (O); El Paso Formation and Bliss Sandstone,

undivided (O�e); and Woods Hollow Shale, Fort Pena Formation,Alsate Shale, Marathon Limestone, and Dagger Flat Sandstone, undivided (O�)

Van Horn Sandstone

Granite

Rhyolite

Llanoria Quartzite (p�la); and Hazel Formation (p�h)

Mundy Breccia and Castner Limestone, undivided (p�mc);and Alamoore Formation (p�a)

Carrizo Mountain Group showing metaigneous rocks (p�i),and metasedimentary rocks (p�s)

Permian rocks, undivided

Quartermaster (Pq) and Cloud Chief (Pcl) Formations; Whitehorse Group,undivided (Pwh); Quartermaster Formation and Whitehorse Group,undivided (Pqw); Blaine Formation (Pb); and Whitehorse Group and

Blaine Formation, undivided (Pwb)

Schiebout, J.A., Rigsby, C.A., Rapp, S.D., Hartnell, J.A., and Standhardt, B.R., 1987, Stratigraphy of the Cretaceous-Tertiary and Paleocene- Eocene transition rocks of Big Bend National Park, Texas: Jour. Geol., v. 95, p. 359–371.

K–Ar ages from: Henry, C.D., and McDowell, F.W., 1986, Geochronology of magmatism in the Tertiary volcanic field, Trans-Pecos Texas, in Price, J.G., and others, eds., Igneous geology of Trans-Pecos Texas: The University of Texas at Austin, Bureau of Economic Geology Guidebook 23, p. 99–122.

Henry, C.D., McDowell, F.W., Price, J.G., and Smyth, R.E., 1986, Compilation of potassium-argon ages of Tertiary igneous rocks, Trans-Pecos Texas: The University of Texas at Austin, Bureau of Economic Geological Circular 86-2, 34 p.

Fingers Formation (Pof); and bolson deposits (Pobo)

Tarantula Gravel

Hannold Hill Member

Black Peaks Member

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El Picacho Formation (Kpi); San Carlos Sandstone (Ksc); Ojinaga (Koj),and Boquillas (Kbo) Formations; Gulfian rocks, undivided (Kg); and

Cretaceous rocks, undivided (K)

; Aguja (Kag) and Pen (Kp) Formations;Javelina Member of Tornillo Formation (PAKj)Austin Chalk (Kau); Boquillas Formation (Kbo); and Gulfian rocks, undivided (Kg)

Buda Limestone (Kbu); Buda Limestone and Del Rio Clay, undivided (Kbd); Boracho (Kbh),and Finlay (Kf) Limestones; Santa Elna Limestone, Sue Peaks Formation, Del Carmen Limestone,

and Telephone Canyon Formation, undivided (Kst) Santa Elena Limestone (Kse); Sue Peaksformation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Kpt);

Fredericksburg Group and Maxon Sandstone, undivided (Kem); Washita (Kw) andFredericksburg (Kfr) Groups; Washita and Fredericksburg Groups, undivided (Kwfr); Duck Creek

Limestone (Kdc); Kiamichi Formation (Kki); Duck Creek Limestone and Kiamichi Formation,undivided (Kdk); Edwards Limestone (Ked); Comanche Peak Limestone (Kcp); Dakota

Formation (Kda); Dakota and Purgatoire Formations, undivided (Kdp); Bissett Conglomerate (Kbi);Maxon Sandstone and Bissett Conglomerate, undivided (Ktb); Maxon Sandstone and

Glen Rose Limestone, undivided (Kt); Glen Rose Limestone (Kgr); Antlers Sand (Ka); andComanchean rocks, undivided (Kc)

Sand sheet (Qs); dune sand sheet (Qds); sand dune (Qsd); andsand deposits, undivided (Qsu)

Alluvium (Qal); and alkali flat deposits (Qaf)

Terrace (Qt), alluvial fan (Qf), caliche (Qc), gypsite (Qgy), land slide (Qls),bolson (Qb), and playa (Qp) deposits; and Quaternary deposits, undivided (Qu)

Leona Formation (Qle); Onion Creek Marl (Qo); Seymour (Qse), *Lingos (Qli), andGatuna (Qg) Formations; Toy Limestone (Qtl); Blackwater Draw (Qbd), Tahoka (Qta),

Double Lakes (Qdl), and Tule (Qtu) Formations; pond (Qun), older alluvial (Qao),and high gravel (Qhg) deposits

Quaternary–Tertiary bolson deposits (QTb); Quaternary–Tertiary deposits,undivided (QT); and Uvalde Gravel (QTu)

Blanco (Pob) and Rita Blanca (Por) Formations;and unnamed Pliocene deposits (Pou)

Ogallala Formation

Goliad Formation

Fleming Formation and Oakville Sandstone, undivided

Catahoula Formation and Frio Clay, undivided (Ocf),Catahoula Formation (Oc); and Frio Clay (Of)

Fill and spoil

Sand sheet (Qs); dune sand sheet (Qds); sand dune (Qsd);silty sheet (Qsi); and clay dune (Qcd)

Alluvium (Qal), subdivided in Rio Grande delta into areas predominantlyclay (Qac), and areas predominantly sand (Qas); and beach-ridge and

barrier-flat sand deposits (Qbr)

Terrace deposits (Qt); and Deweyville Formation (Qd), with higher level, (Qd?)

Beaumont Formation subdivided into areas predominantly clay, (Qbc),areas predominantly sand (Qbs), in the Rio Grande delta area clay veneer

over meanderbelt sand (Qbv), and barrier island deposits (Qbb)

Lissie Formation

High gravel deposits

Willis Formation

Goliad Formation

Fleming Formation and Oakville Sandstone, undivided (Mfo);Fleming Formation (Mf); and Oakville Sandstone (Mo)

Catahoula Formation

Shitsett (OEw) and Nash Creek (On) Formations

Manning (Em), Wellborn (Ewb), and Yazoo (Eya) Formations

Caddell (Eca) and Moodys Branch (Emb) Formations

Yegua Formation

Cook Mountain Formation

Sparta Sand

Weches Formation

Queen City Sand

Reklaw Formation (Er); Carrizo Sand (Ec); Calvert Bluff (EPA c),As),Simsboro, (P and Hooper (PAh) Awi);, Formations; Wilcox Group, undivided (EP

Wills Point (PAw), and Kincaid (PAk), Formations; Midway Group, undivided (PAmi); andReklaw Formation, Carrizo Sand, and Wilcox and Midway Groups, undivided (EPAu)

Jackson Group, Undivided (OEj); Whitsett Formation (OEw); Manning,Wellborn, and Caddell Formations, undivided (Ejl); Manning (Em), Wellborn (Ewb),

and Caddell (Eca) Formations

Yegua Formation

Laredo Formation (El); Cook Mountain Formation (Ecm);and Sparta Sand (Es)

El Pico Clay (Eep); Weches Formation (Ew); and Queen City Sand (Eqc)

Bigford (Eb) and Reklaw (Er) Formations

Indio Formation (EPAin); and Wilcox Group, undivided (EPAwi)

Kincaid Formation (PAk); and Midway Group, undivided (PAmi)

Escondido Formation (Kes); and Navarro Group andMarlbrook Marl, undivided (Knb)

Olmos (Kol) and San Miguel (Ksm) Formations; Upson Clay (Kuc);Anacacho Limestone (Kac); Pecan Gap (Kpg) and Austin (Kau) Chalks;

and igneous rocks of Austin age (Ki)

Navarro and Taylor Groups, undivided (Knt); Navaro Group and Marlbrook Marl,undivided (Knb); Kemp Clay and Corsicana Marl, undivided (Kkc); Kemp Clay (Kke);

Nacatoch Sand (Kns); Navarro Group, undivided (Kna); Neylandville andMarlbrook Marls, undivided (Knm); Neylandville Marl (Kne); Marlbrook Marl (Kmb);

Pecan Gap Chald (Kpg); Wolfe City Sand (Kwc); Ozan Formation (Ko); Annona Chalk (Kan);and Upper Cretaceous rocks, undivided (K)

Austin Chalk (Kau); Gober Chalk and Roxton Limestone (Kgc); Brownstown Marl (Kbr); Blossom Sand (Kbl); Bonham Formation (Kbn);

Ector Chalk (Ker); and Upper Cretaceous rocks, undivided (K)

Boquillas (Kbo) and Eagle Ford (Kef) Formations; Buda Limestone (Kbu);Del Rio Clay (Kdr); Buda Limestone and Del Rio Clay, undivided (Kbd);Santa Elena Limestone (Kse); Salmon Peak Limestone (Ksa); Sue Peaks

Formation (Ksu); McKnight Formation (Kmk); Del Carmen Limestone (Kdm);West Nueces Formation (Kwn); Devils River (Kdv), Edwards (Ked), and

Comanche Peak (Kcp) Limestones; Hensell Sand (Kh); Glen Rose Limestone (Kgr);Paluxy Sand (Kpa); Travis Peak Formation (Ktp); Twin Mountains Formation (Ktm);

Edwards Limestone and Antlers Sand, undivided (Kea); Comanche PeakLimestone and Walnut Clay, undivided (Kcw); Antlers Sand (Ka); and

Comanche Peak Limestone, Walnut Clay, and Antlers Sand, undivided (Kca)

Cow Creek Limestone, Hammett Shale, and Sycamore Sand, undivided

Eagle Ford Formation and Buda Limestone, undivided (Keb); Eagle FordFormation (Kef); Eagle Ford and Woodbine Formations, undivided (Kew);

Woodbine Formation (Kwb); Del Rio Clay and Georgetown Limestone,undivided (Kdg); Buda Limestone and Del Rio Clay, undivided (Kbd);

Grayson Marl and Main Street Limestone, undivided (Kgm); GeorgetownLimestone (Kgt); Pawpaw Formation and upper limestone unit of Weno

Limestone, undivided (Kpw); lower part of Washita Group (Kwl); undividedpart of Washita Group (Kwu); Duck Creek Limestone (Kdc); Pawpaw

Formation, Weno Limestone, and Denton Clay, undivided (Kpd); Fort WorthLimestone and Duck Creek Formation, undivided (Kfd); Fredericksburg Group

(Kfr); Edwards and Comanche Peak Limestones, undivided (Kec); Walnut Clay (Kwa);undivided parts of Washita and Fredericksburg Groups (Kwf); undivided part ofFredericksburg Group (Kfu); Kiamichi Formation (Kki); Goodland Limestone and

Walnut Clay, undivided (Kgw); and Upper Cretaceous rocks, undivided (K)

Paluxy Sand (Kpa); Glen Rose Limestone (Kgr); Twin MountainsFormation (Ktm); and Antlers Sand (Ka)

20

25

30

35

40

45

50

Fault—Ball shows downthrown side

Thrust Fault—Barbs on overriding plate

Manuscript geologic map by E.W. Collins, Bureau of Economic Geology,The University of Texas at Austin used for Georgetown—Round Rock area,Williamson County, Texas

*Lingos reference:Caran, S.C., and Baumgardner, R.W., Jr., in press, Quaternary stratigraphy and paleoenvironments of the Texas Rolling Plains: Geological Society of America Bulletin.

Carrizo Sand

Buda Limestone (Kbu); Buda Limestone and San Martine Member of BorachoLimestone, undivided (Kbb); Buda Limestone and Eagle Mountains Sandstone,undivided (Kbe); Buda Limestone and Del Rio Clay, undivided (Kbd); Boracho

and Finlay Limestones, undivided (Khf); Espy Formation (Key); Loma Plata (Klp),Boracho (Kbh), and Santa Elena (Kse) Limestones; Benevides Formation (Kb);

Finlay Limestone (Kf); Benevides Formation and Finlay Limestone, undivided (Kbf);Sue Peaks Formation (Ksu); Del Carmen Limestone (Kdm); Cox Sandstone (Kcx);

Shafter Formation (Ksh); Glen Rose Limestone (Kgr); Campagrande (Kcg),Bluff Mesa (Kbm), Yearwood (Kye), Yucca (Kyu), and Presidio (Kpr) Formations;

Etholen Conglomerate (Ket); Torcer Formation (Kto); Comanchean rocks, undivided (Kc);and Cretaceous rocks, undivided, (K)

Chinle (�c), Trujillo (�j), and Tecovas (�v) Formationsand Dockum Group, undivided (�d)

Malone Formation Morrison Formation

San Angelo Formation

Clear Fork Group

Lueders (Plu), Talpa (Pta), Grape Creek (Pgc),Bead Mountain (Pbe), and Waggoner Ranch (Pwr) Formations

Jagger Bend and Valera Formations, undivided (Pjv);Elm Creek (Pec), and Petrolia (Pp) Formations

Admiral (Pad) and Coleman Junction (Pcj) Formations; Admiral andColeman Junction Formations, undivided (Paj); Santa Anna Branch Shaleand Sedwick and Moran Formations, undivided (Pss); Santa Anna BranchShale (Psb); Nocona (Pn), Sedwick (Pse), and Moran (Pmo) Formations;

Sedwick and Moran Formations, undivided (Psm); andArcher City Formation (Pac)

Pueblo (Ppu), Harpersville (P�h), Thrifty and Graham Formations,undivided (�tg), and Markley (P�ma) Formations

Home Creek Limestone and Colony Creek Shale, undivided (�hc);Ranger Limestone and Placid Shale, undivided (�rp); Ranger

Limestone (�r); Winchell Limestone (�w); Wolf Mountain Shale (�wm);Cedarton Shale and Adams Branch Limestone, undivided (�ca);

Ventioner Formation (�v); Canyon Group, undivided (�cn); Palo Pinto (�pp),and Mineral Wells (�mw) Formations; Palo Pinto (�pp) and Mineral Wells,

undivided (�pm); Jasper Creek Formation (�jc); Chico Ridge Limestone (�cr);Willow Point (�wp), Brazos River (�br), and Mingus (�m) Formations;

pre-Brazos River Rocks, undivided (�pb); Grindstone Creek expanded (�gr), and Lazy Bend (�lb) Formations; unnamed Pennsylvanian rocks (�u);

and Strawn Group, undivided (�st)

Smithwick Formation

Marble Falls Limestone

Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring,and Stribling Formations, and Pillar Bluff Limestone, undivided

Starke Limestone

Burnam Limestone

Honeycut Formation

Gorman Formation

Tanyard Formation

Wilberns Formation showing San Saba Member (�s), and Point Peak,Morgan Creek Limestone, and Welge Sandstone Members, undivided, (�pw)

Riley Formation showing Lion Mountain Sandstone and Cap MountainLimestone Members, undivided (�lc), and Hickory Sandstone Member, (�h)

Younger granitic intrusion

Town Mountain Granite

Red Mountain Gneiss

Big Branch Gneiss

Coal Creek Serpentinite

Mafic igneous rocks

Packsaddle Schist

Lost Creek Gneiss

Valley Spring Gneiss

6. Delaho Formation and unit 9 of Rawls Formation (-M-d); Bofecillos volcano volcanic rocks, including units 1–8 of Rawls Formation and lava flows in upper part of Fresno Formation (Or); Santana Tuff from Sierra Rica caldera in Mexico (Osa); San Carlos Tuff from San Carlos caldera in Mexico (Osc); South Rim Formation from Pine Canyon caldera (Os); Chisos Formation of Schiebout et al. (1987) and the Big Yellow Sandstone Member of their Tornillo Formation, undivided (Oec); and Eocene volcanic rocks (Ev)

7. Black Gap area volcanic rocks (-M-b); Jones Basalt (previously mapped as Petan but not related to type locality) (Oj); and Devils Graveyard volcanic rocks (Oeg)

8. Jones Basalt (Oj); and Duff Formation (with Decie Member (Ode), from Paisano caldera shown separately), Cottonwood Spring Basalt, Potato Hill Andesite, Sheep Canyon Basalt, Crossen Trachyte, and Pruett Formation, undivided (Oed)

9. Jones Basalt (Oj); younger volcanic rocks of Davis Mountains area, including Brooks Mountain, Goat Canyon, Medley, Barrel Springs, Wild Cherry, Eppenauer Ranch, Mount Locke, and Merrill Formations, (Od); and older volcanic rocks of Davis and Barilla Mountains, including Sheep Pasture, Sleeping Lion, Frazier Canyon, Adobe Canyon, and Limpia Formations, Gomez Tuff, Star Mountain Rhyolite, and Huelster Formation (Ed)

1. Tertiary intrusive rocks, undivided (Ti); Quitman Mountains caldera volcanic rocks, and volcanic rocks of Sneed (Cox) Mountain and west of Victoria Peak, (Oq); Eagle Mountains caldera volcanic rocks (Oe); and Van Horn Mountains caldera volcanic rocks (Evh)

2. Miocene intrusive rocks (-M-i); Oligocene intrusive rocks (Oi); Wiley Mountains caldera volcan rocks (Ewm); and Eocene intrusive rocks (Ei)

3. Vieja Group, including Bracks Rhyolite, Chambers and Colmena Tuffs, and Gill Breccia (Oev)

4. Chinati Mountains caldera volcanic rocks, including Chinati Mountains Group, Mitchell Mesa Ignimbrite, and type area of Petan Basalt (Ocm); upper part of Shely Group, including Tm4 of Morita Ranch Formation (Osh); Infiernito caldera volcanic rocks, including Capote Mountain Tuff, Tsh2 of Shely Group, Buckshot Ignimbrite, and Tm1 of Morita Ranch Formation (Ein)

5. Delaho and Rawls Formations, undivided (-M-O); Perdiz Conglomerate, Tascotal Formation, and tuffaceous sediments of Fresno Formation, (Opf); Jones Basalt (Oj); and Tm2 and Tm3 units of Morita Ranch Formation (possibly from caldera in Cienega Mountain area) (Omr)

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