Green River Basin Plan II - Available Groundwater Determination Technical Memorandum Plate 7

GIS Unit Wyoming stratigraphic unit Colorado stratigraphic unit Utah stratigraphic unit 2007 Wyoming Statewide Framework Symbol Age and general lithology Wyoming state map unit Western GRB and Northern GRB and Eastern GRB and Washakie and Little Great Divide Basin Water Plan – Aquifer classification Wyoming Colorado Utah southern Overthrust Belt northern Overthrust Belt Rock Springs Uplift Snake River basins CENOZOIC UNITS Water Water Water surface water Water (surface) Water (surface) Water (surface) Water (surface) Water (surface) Water (surface) Water (surface) Water (surface) not classified Ice -- -- glacial ice Glacial ice -- Glacial ice ------not classified Qa Qa Qa -Holocene: alluvium & Alluvium and colluvium Alluvium and colluvium Alluvium and colluvium Alluvium and colluvium Alluvium and colluvium Alluvium and colluvium Modern alluvium Surficial alluvium and Major Aquifer - Alluvial colluvium deposits colluvium Qls Ql Qls Pleistocene-Holocene: landslide & Landslide deposits Landslide deposits Landslide deposits Landslide deposits Landslide deposits Landslide deposits Landslide deposits Surficial landslide deposits Minor Aquifer glacial drift deposits Qs Qe Qe Holocene: dune sand & loess Dune sand/loess (eolian) deposits Dune sand/loess (eolian) Dune sand/loess (eolian) deposits Dune sand/loess (eolian) deposits Dune sand/loess (eolian) deposits Dune sand/loess (eolian) deposits Eolian deposits Surficial eolian deposits Minor Aquifer deposits deposits Ql -- -- Pleistocene-Holocene: playa lake Playa lake/other lacustrine deposits -- -- Playa lake/other lacustrine deposits Playa lake/other lacustrine deposits Playa lake/other lacustrine deposits -- -- Minor Aquifer (non-glacial) deposits Qg Qg Qg Pleistocene-Holocene: glacial Glacial deposits Glacial deposits Glacial deposits Glacial deposits Glacial deposits -- Gravels/alluvium/older glacial Surficial glacial deposits Minor Aquifer Qdo deposits drift Qi -- -- Pleistocene: alkalic extrusive and Alkali extrusive/intrusive igneous -- -- Alkali extrusive/intrusive igneous ------Unclassified

Quaternary units intrusive igneous rocks rocks rocks (Leucite Hills) Qt Qgo Qao Pleistocene-Holocene: Gravel, pediment, & fan deposits Gravel, pediment, & fan Gravel, pediment, & fan deposits -- Gravel, pediment, & fan deposits Gravel, pediment, & fan deposits Older gravels and alluviums Surficial older alluvium and Minor Aquifer unconsolidated gravel deposit deposits colluvium Qu -- Qg Pleistocene-Holocene: alluvium & Undivided surficial deposits Undivided surficial deposits ------Surficial glacial deposits/Bishop Minor Aquifer T4 colluvium deposits Conglomerate QTg -- Qg -Pleistocene: gravel Terrace gravel Terrace gravel -- Terrace gravel ------Surficial glacial deposits/Bishop Minor Aquifer T4 deposit Conglomerate -- Tui -- -Pliocene: granitoid & Intrusive & extrusive igneous Intrusive & extrusive ------Upper Tertiary intrusive rocks -- Unclassified basalt rocks igneous rocks

Tmu -- -- Upper Miocene: sandstone & Upper Miocene rocks (undivided) -- -- Upper Miocene rocks (undivided) ------Minor Aquifer claystone

Tm Tbp T5 Miocene: sandstone & Miocene rocks (undivided) -- Miocene rocks (undivided) Miocene rocks (undivided) Miocene rocks (undivided) Miocene rocks (undivided) Browns Park Formation Minor Aquifer conglomerate

Tbf Tv -- Miocene: basalt Basalt flows/intrusive igneous ------Basalt flows/intrusive igneous -- Volcanic rocks NW -- Unclassified upper Tertiary units Tui rocks rocks Colorado/intrusive rocks

Tbi Tos T4 : conglomerate Bishop Conglomerate Bishop Conglomerate -- Bishop Conglomerate -- -- White River Fm/Bishop Bishop Conglomerate Minor Aquifer Conglomerate Twru -- -- Oligocene: medium-grained mixed White River Fm: Upper -- White River Fm: Upper ------Minor Aquifer clastic & conglomerate conglomerate member conglomerate member Twr -- -- Oligocene: fine- & medium- White River Formation ------White River Formation -- -- Minor Aquifer grained mixed clastic Toe -- -- -Oligocene: mixed Oligocene/Upper-Middle Eocene -- Oligocene/Upper-Middle Eocene ------Minor Aquifer clastic/volcanic & medium-grained rocks rocks mixed clastic Tip -- -- Eocene: conglomerate Ice Point Conglomerate ------Ice Point Conglomerate -- -- Minor Aquifer Twa -- -- Eocene: medium- & fine-grained Washakie Formation ------Washakie Formation ------Minor Aquifer mixed clastic Tb Tb T3 Eocene: fine-grained mixed clastic Bridger Formation Bridger Formation Bridger Formation -- Bridger Formation Bridger Formation Bridger Formation Major Aquifer - Sandstone & mixed clastic/volcanic Tcg -- -- Eocene: conglomerate Crooks Gap Conglomerate ------Crooks Gap Conglomerate -- -- Minor Aquifer Tgl Tglm -- Eocene: oil shale & mixed Green River Fm: Laney Member Green River Fm: Laney Green River Fm: Laney Member Green River Fm: Laney Member Green River Fm: Laney Member Green River Fm: Laney Member Green River Fm: Laney -- Major Confining Unit clastic/carbonate Member Member Tgw -- -- Eocene: fine-grained mixed clastic Green River Fm: Wilkins Peak Green River Fm: Wilkins -- Green River Fm: Wilkins Peak Green River Fm: Wilkins Peak ------Marginal Aquifer & mixed clastic/carbonate Member Peak Member Member Member Tgwt Tgt -- Eocene: mixed clastic/carbonate & Green River Fm: Wilkins Peak -- -- Green River Fm: Wilkins Peak Green River Fm: Wilkins Peak -- Green River Fm: Tipton -- Marginal Aquifer Tgt(2) fine-grained clastic Mbr & Tipton Shale Mbr/Tongue Mbr & Tipton Shale Mbr/Tongue Mbr & Tipton Shale Mbr/Tongue Tongue Tgt Tgt -- Eocene: oil shale & mixed Green River Fm: Tipton Shale ------Green River Fm: Tipton Shale Green River Fm: Tipton Shale Green River Fm: Tipton Shale -- Major Confining Unit clastic/carbonate Member/Tongue Member/Tongue Member/Tongue Member/Tongue Tglu Tglu -- Eocene: fine-grained mixed clastic Green River Fm: Luman Tongue ------Green River Fm: Luman Tongue Green River Fm: Luman Tongue Green River Fm: Luman -- Major Confining Unit & oil shale Tongue Tgrw -- -- Eocene: mudstone & sandstone Green River & Wasatch Green River & Wasatch ------Major Aquifer - Sandstone Formations Formations () Twc Twc T1 Eocene: fine- & medium-grained Wasatch Fm: Cathedral Bluffs Wasatch Fm: Cathedral Wasatch Fm: Cathedral Bluffs Wasatch Fm: Cathedral Bluffs Wasatch Fm: Cathedral Bluffs -- Wasatch Fm: Cathedral Bluffs Fort Union & Wasatch Fms Minor Aquifer mixed clastic Tongue Bluffs Tongue Tongue Tongue Tongue Tongue Twn Twn T1 Eocene: sandstone & shale Wasatch Fm: Niland Tongue ------Wasatch Fm: Niland Tongue Wasatch Fm: Niland Tongue Wasatch Fm: Niland Tongue Fort Union & Wasatch Fms Minor Aquifer Twd -- -- Eocene: clastic & medium-grained Wasatch Fm: Diamictite & Wasatch Fm: Diamictite & Wasatch Fm: Diamictite & ------Major Aquifer - Sandstone

lower Tertiary units mixed clastic sandstone sandstone sandstone Twlc -- -- -Eocene: mudstone & Wasatch Fm: La Barge & Chappo Wasatch Fm: La Barge & Wasatch Fm: La Barge & Chappo ------Major Aquifer - Sandstone conglomerate Members Chappo Members Members Twg -- -- Eocene: fine-grained mixed clastic Wasatch & Green River Fms: New -- Wasatch & Green River Fms: New ------Major Aquifer - Sandstone & mixed clastic/carbonate Fork Tongue of Wasatch Fm & Fork Tongue of Wasatch Fm & Fontenelle Tongue of Green River Fontenelle Tongue of Green River Fm Fm Twm Tw T1 Eocene: sandstone & fine-grained Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Formation Fort Union & Wasatch Fms Major Aquifer - Sandstone mixed clastic Tw Tw T1 Eocene: mudstone & sandstone Wasatch Fm: Main body Wasatch Fm: Main body Wasatch Fm: Main body ------Wasatch Formation Fort Union & Wasatch Fms Major Aquifer - Sandstone

Tbs -- -- Paleocene-Eocene: conglomerate Battle Spring Formation ------Battle Spring Formation -- -- Major Aquifer - Sandstone Tp -- -- Eocene: conglomerate & medium- Pass Peak Formation & -- Pass Peak Formation & equivalents ------Minor Aquifer grained mixed clastic equivalents Tep -- -- Paleocene-Eocene: conglomerate Conglomerate of Roaring Creek -- Conglomerate of Roaring Creek ------Minor Aquifer Th -- -- Paleocene: medium- & fine- Hoback Formation -- Hoback Formation ------Minor Aquifer grained mixed clastic Tdb -- -- Paleocene: medium- & fine- Devils Basin Formation -- Devils Basin Formation ------Minor Aquifer grained mixed clastic Tfu Tf T1 Paleocene: sandstone & shale Fort Union Formation Fort Union Formation Fort Union Formation Fort Union Formation Fort Union Formation Fort Union Formation Fort Union & Wasatch Fms Major Aquifer - Sandstone TKp -- -- Upper -Paleocene: Pinyon Conglomerate -- Pinyon Conglomerate ------Minor Aquifer conglomerate & sandstone TKe -- -- Upper Cretaceous-Paleocene: Evanston Formation Evanston Formation ------Minor Aquifer siltstone & sandstone MESOZOIC UNITS Kl Kl K3 Upper Cretaceous: sandstone & -- -- Lance Formation Lance Formation Lance Formation Lance Formation Mesaverde Group/Lewis Minor Aquifer shale Shale/Fox Hills Sandstone/Lance Fm Kfh -- -- Upper Cretaceous: sandstone & Fox Hills Sandstone -- Fox Hills Sandstone Fox Hills Sandstone Fox Hills Sandstone Fox Hills Sandstone -- -- Minor Aquifer shale Kfl -- -- Upper Cretaceous: sandstone & Fox Hills Sandstone & Lewis -- Fox Hills Sandstone & Lewis Shale Fox Hills Sandstone & Lewis Fox Hills Sandstone & Lewis Fox Hills Sandstone & Lewis -- -- Minor Aquifer (Fox Hills Sandstone) shale Shale Shale Shale Shale Kle Kls K3 Upper Cretaceous: shale & Lewis Shale -- Lewis Shale Lewis Shale Lewis Shale Lewis Shale Lewis Shale Mesaverde Group/Lewis Major Confining Unit sandstone Shale/Fox Hills Sandstone/Lance Fm Kmv Kmv K3 Upper Cretaceous: sandstone & Mesaverde Group Mesaverde Group Mesaverde Group Mesaverde Group Mesaverde Group Mesaverde Group Mesaverde Group (undivided) Mesaverde Group/Lewis Major Aquifer - Sandstone Kw shale & Williams Fork Fm & Iles Fm Shale/Fox Hills Sandstone/Lance Fm Kal -- -- Upper Cretaceous: sandstone & Almond Fm of Mesaverde Group -- -- Almond Formation of Mesaverde Almond Formation of Mesaverde Almond Formation of Mesaverde -- -- Minor Aquifer shale Group Group Group Ke -- -- Upper Cretaceous: sandstone & Ericson Sandstone of Mesaverde -- -- Ericson Sandstone of Mesaverde ------Major Aquifer - Sandstone conglomerate Group Group Kr -- -- Upper Cretaceous: sandstone & Rock Springs Fm of Mesaverde -- -- Rock Springs Fm of Mesaverde ------Minor Aquifer mudstone Group Group Kbl -- -- Upper Cretaceous: sandstone & Blair Fm of Mesaverde Group -- -- Blair Fm of Mesaverde Group ------Minor Aquifer shale Kav -- -- Upper Cretaceous: sandstone & Adaville Formation Adaville Formation ------Minor Aquifer fine-grained mixed clastic Kh -- -- Upper Cretaceous: mudstone Hilliard Shale Hilliard Shale ------Major Confining Unit Kbb -- -- Upper Cretaceous: medium- Blind Bull Formation -- Blind Bull Formation ------Minor Aquifer grained & fine-grained mixed clastic Ksb -- -- Upper Cretaceous: sandstone & Sohare Fm/Bacon Ridge -- Sohare Fm/Bacon Ridge Sandstone ------Minor Aquifer Upper units Cretaceous coal Sandstone Kba -- -- Upper Cretaceous: shale & Baxter Shale -- -- Baxter Shale ------Major Confining Unit sandstone Kc Km -- Upper Cretaceous: shale & Cody Shale -- Cody Shale Cody Shale -- Cody Shale (Lower-Upper -- Major Confining Unit sandstone Cretaceous) Ksn Km K2 Upper Cretaceous: shale & mixed Steele Shale/Niobrara Fm ------Steele Shale/Niobrara Fm Steele Shale/Niobrara Fm Mancos Shale/Frontier Mancos Shale/Mowry Major Confining Unit Kfd clastic/volcanic Sandstone/Mowry Shale Shale/Frontier Fm/Blair Members of the Mancos Fm/Hilliard Shale/Adaville Fm Shale/Dakota Sandstone Ks -- -- Upper Cretaceous: shale & mixed Steele Shale ------Steele Shale ------Major Confining Unit clastic/volcanic Kn -- -- Upper Cretaceous: limestone & ------Niobrara Formation ------Major Confining Unit fine-grained mixed clastic Kf Km K2 Upper Cretaceous: sandstone & Frontier Formation Frontier Formation Frontier Formation Frontier Formation Frontier Formation Frontier Formation Mancos Shale Mancos Shale/Mowry Minor Aquifer shale Shale/Frontier Fm/Blair Fm/Hilliard Shale/Adaville Fm Kft -- -- Upper-Lower Cretaceous: Frontier Fm/Mowry Shale/ -- -- Frontier Fm/Mowry Frontier Fm/Mowry Frontier Fm/Mowry -- -- Major Confining Unit and sandstone & shale Thermopolis Shale Shale/Thermopolis Shale Shale/Thermopolis Shale Shale/Thermopolis Shale Minor/Marginal Aquifer (Frontier Formation and Muddy Sandstone) Kss -- K1 Lower Cretaceous: mudstone & Sage Junction/Quealy/Cokeville/ Sage Junction/Quealy/ ------Dakota Fm/Cedar Mountain Minor Aquifer sandstone Thomas Fork/Smiths Fms Cokeville/Thomas Fm/Sage Junction Fm/Aspen Fork/Smiths Fms Shale Ka -- K2 Lower Cretaceous: mudstone & Aspen Shale Aspen Shale Aspen Shale ------Mancos Shale/Mowry Major Confining Unit mixed clastic/volcanic Shale/Frontier Fm/Blair Fm/Hilliard Shale/Adaville Fm Kbr -- -- Lower Cretaceous: shale & Bear River Formation Bear River Formation Bear River Formation ------Marginal Aquifer sandstone

Kmt Km K2 Lower Cretaceous: shale & Mowry Shale/Thermopolis Shale -- Mowry/Thermopolis Shale Mowry Shale/Thermopolis Shale Mowry Shale/Thermopolis Shale Mowry Shale/Thermopolis Shale Mancos Shale/Frontier Mancos Shale/Mowry Major Confining Unit (Mowry Shale Kfd sandstone Sandstone/Mowry Shale Shale/Frontier Fm/Blair and Thermopolis Shale) Members of the Mancos Fm/Hilliard Shale/Adaville Fm Shale/Dakota Sandstone Lower Cretaceous units Cretaceous Lower Kg -- K1 Lower Cretaceous: mudstone & Gannett Group Gannett Group Gannett Group ------Dakota Fm/Cedar Mountain Minor Aquifer sandstone Fm/Sage Junction Fm/Aspen Shale KJ -- -- -Lower Cretaceous: Cloverly/Morrison Formations -- -- Cloverly/Morrison Formations Cloverly/Morrison Formations Cloverly/Morrison Formations -- -- Major Aquifer - Sandstone sandstone & claystone (Cloverly Formation) KJs KJds J1 -Lower Cloverly/Morrison/Sundance Fms ------Cloverly/Morrison/Sundance Fms Cloverly/Morrison/Sundance Fms Dakota/Morrison/Sundance Stump Fm/Entrada Major Aquifer - Sandstone J2 Cretaceous: fine-grained clastic Fms Sandstone/Carmel Fm/Curtis (Cloverly Formation) and medium-grained mixed clastic Fm/Morrison Fm KJg KJds J1 Middle Jurassic-Lower Cloverly/Morrison/Sundance/ Cloverly/Morrison/ Cloverly/Morrison/Sundance/ Cloverly/Morrison/Sundance/ -- Cloverly/Morrison/Sundance/ Dakota/Morrison/Sundance Stump Fm/Entrada Major Aquifer - Sandstone J2 Cretaceous: fine-grained clastic Gypsum Spring Fms Sundance/Gypsum Spring Gypsum Spring Fms Gypsum Spring Fms Gypsum Spring Fms Fms Sandstone/Carmel Fm/Curtis (Cloverly Formation) and medium-grained mixed clastic Fms Fm/Morrison Fm -- Jm -- Jurassic: sandstone and ------ (Colorado -- Marginal Aquifer shale/mudstone unit only) Jsg -- J1 Middle Jurassic-Lower Sundance/Gypsum Spring Fms Sundance/Gypsum Spring Sundance/Gypsum Spring Fms Sundance/Gypsum Spring Fms -- Sundance/Gypsum Spring Fms -- -- Marginal Aquifer Cretaceous: sandstone and shale Fms J!n J!mg Jg (?)-Jurassic: sandstone Nugget Sandstone Nugget Sandstone Nugget Sandstone Nugget Sandstone Nugget Sandstone Nugget Sandstone Morrison/Curtis/Entrada/Glen Glen Canyon Sandstone/Nugget Major Aquifer - Sandstone

Jurassic units Canyon Fms (Navajo) Sandstone/Chinle Fm

J!nd J!mg Jg Lower Triassic-Jurassic: siltstone Nugget Sandstone/Ankareh Fm/ Nugget Sandstone/Ankareh Nugget Sandstone/Ankareh Fm/ ------Morrison/Curtis/Entrada/Glen Triassic and Jurassic rocks Minor Aquifer (Thaynes Limestone) !1 and sandstone Thaynes Limestone/Woodside Fm/Thaynes Limestone/ Thaynes Limestone/Woodside Canyon Fms (undivided) and Marginal Aquifer (Woodside Shale/Dinwoody Fm Woodside Shale/Dinwoody Shale/Dinwoody Fm Formation and Dinwoody Fm Formation) Jst -- J1 Middle-Upper Jurassic: fine- Stump Fm/Preuss Sandstone or Stump Fm/Preuss Sandstone Stump Fm/Preuss Sandstone or ------Minor Aquifer (Twin Creek grained mixed clastic and Redbeds/Twin Creek Limestone or Redbeds/Twin Creek Redbeds/Twin Creek Limestone Limestone) limestone Limestone !ad -- !1 Lower-Upper Triassic: mixed Ankareh Fm/Thaynes Ankareh Fm/Thaynes Ankareh Fm/Thaynes ------Dinwoody Fm/Woodside Minor Aquifer (Thaynes Limestone) clastic/carbonate and fine-grained Limestone/Woodside Limestone/Woodside Limestone/Woodside Shale/Thaynes Limestone & and Marginal Aquifer (Woodside mixed clastic Shale/Dinwoody Fm Shale/Dinwoody Fm Shale/Dinwoody Fm other fms Formation and Dinwoody Formation) !c -- !1 Lower-Upper Triassic: siltstone Chugwater Formation Chugwater Formation Chugwater Formation Chugwater Formation Chugwater Formation -- Dinwoody Fm/Woodside Marginal Aquifer (Woodside and shale Shale/Thaynes Limestone & Formation and Dinwoody other fms Formation) and Minor Aquifer (Thaynes Limestone) !cd !Pcp !1 Lower-Upper Triassic: mudstone Chugwater/Dinwoody Fms Chugwater/Dinwoody Fms Chugwater/Dinwoody Fms Chugwater/Dinwoody Fms -- -- Chinle/Moenkopi/Park City Dinwoody Fm/Woodside Marginal Aquifer (Dinwoody Triassic units !Pr and limestone Fms; Nugget/Jelm/Popo Shale/Thaynes Limestone & Formation) Agie/Chugwater/Red other fms Peak/Forelle, Satanka & Goose Egg Fms PALEOZOIC UNITS MzPz -- -- Upper -Lower Mesozoic & Paleozoic rocks ------Mesozoic & Paleozoic (undivided) Mesozoic & Paleozoic (undivided) -- -- Minor Aquifer Cretaceous: sedimentary rock units (undivided) and clastic Pp -- P2 : shale and phosphorite & related Phosphoria Formation & Phosphoria Formation & related Phosphoria Formation & related Goose Egg Formation/Group Goose Egg Formation/Group -- Park City Formation & related Minor Aquifer rocks related rocks rocks rocks rocks P$Ma -- P$ Upper Mississippian-Permian: Phosphoria/Wells/Amsden Fms Phosphoria/Wells/Amsden Phosphoria/Wells/Amsden Fms ------Weber Sandstone Minor Aquifer P&M $ limestone and sandstone Fms PM P$w P$ Upper Mississippian-Permian: Tensleep Sandstone/Amsden Fm Tensleep Sandstone/Amsden Tensleep Sandstone/Amsden Fm Tensleep Sandstone/Amsden Fm Tensleep Sandstone/Amsden Fm Tensleep Sandstone/Amsden Fm Minturn or Morgan Fms/Weber Morgan Fm/Round Valley Major Aquifer - Limestone $mr $ sandstone and carbonate Fm Sandstone & Maroon Fm Limestone (Tensleep Sandstone)

Pzr M^ml -- Paleozoic: -Permian rock Paleozoic rocks (undivided) ------Paleozoic rocks (undivided) Paleozoic rocks (undivided) Madison Limestone & Lodore -- Major Aquifer - Limestone units Fm (Madison Limestone) Mm Mm M1 Lower-Upper Mississippian: Madison Limestone or Group Madison Limestone or Madison Limestone or Group Madison Limestone or Group Madison Limestone or Group Madison Limestone or Group Mississippian and Cambrian Madison Limestone Major Aquifer - Limestone limestone and dolomite Group rocks (Madison Limestone) Paleozoic units MD -- M2 Upper -Upper Madison Limestone/Darby Fm Madison Limestone/Darby Madison Limestone/Darby Fm ------Doughnut Shale/Fm/Humbug Major Aquifer - Limestone Mississippian: limestone and Fm Fm/Madison Limestone (Madison Limestone) dolomite O^ -- -- Middle Cambrian-Upper Bighorn Dolomite/Gallatin Bighorn Dolomite/Gallatin Bighorn Dolomite/Gallatin Bighorn Dolomite/Gallatin ------Major Aquifer - Limestone : limestone and Limestone/Gros Ventre Fm Limestone/Gros Ventre Fm Limestone/Gros Ventre Fm Limestone/Gros Ventre Fm (Bighorn Dolomite) dolomite ^r ^l ^1 Middle-Upper Cambrian: Cambrian rocks (undivided) Cambrian rocks (undivided) Cambrian rocks (undivided) Cambrian rocks (undivided) Cambrian rocks (undivided) Cambrian rocks (undivided) Lodore Formation & Sawatch Lodore Sandstone/Formation Major Aquifer - Limestone limestone and sandstone Quartzite (Flathead Sandstone) UNITS -- Yu P^s Middle : quartzite and ------Uinta Mountain Group Uinta Mountain Group Marginal Aquifer conglomerate Xsv Xfh -- Early Proterozoic: Metasedimentary/metavolcanic ------Metasedimentary/metavolcanic -- Precambrian Interlayered Felsic -- Major Confining Unit (Precambrian) metasedimentary & metavolcanic rocks rocks and Hornblende Gneisses rock Xlc -- -- Early Proterozoic: Metasedimentary rocks - Libby ------Metasedimentary rocks - Libby ------Major Confining Unit (Precambrian) metasedimentary rock Creek Group Creek Group Xdl -- -- Early Proterozoic: Metasedimentary rocks - Deep ------Metasedimentary rocks - Deep ------Major Confining Unit (Precambrian) metasedimentary rock Lake Group Lake Group Xgy Xg -- Early Proterozoic: granitoid Granitic rocks of 1,700 Ma Age ------Granitic rocks of 1,700 Ma Age -- Granitic rocks of 1,700 Ma Age -- Major Confining Unit (Precambrian) Group Group Group Xqd -- -- Early Proterozoic: quartz diorite Quartz diorite ------Quartz diorite ------Major Confining Unit (Precambrian) Xm Xm -- Early Proterozoic: gabbroid Mafic intrusive rocks ------Mafic intrusive rocks -- Mafic rocks of 1,700 Ma Age -- Major Confining Unit (Precambrian) Group

Wgn -- -- Late Archean: granitic gneiss Granite gneiss -- Granite gneiss -- Granite gneiss ------Major Confining Unit (Precambrian) WVsv -- -- Middle-Late Archean: Metasedimentary/metavolcanic -- Metasedimentary/metavolcanic -- Metasedimentary/metavolcanic ------Major Confining Unit (Precambrian) Precambrian units metasedimentary & metavolcanic rocks rocks rocks rock Ws Wr P^m Late Archean: metasedimentary Metasedimentary rocks -- Metasedimentary rocks ------Red Creek Quartzite Red Creek Quartzite Major Confining Unit (Precambrian) rock Wg -- -- Late Archean: granitoid Granitic rocks of 2,600 Ma -- Granitic rocks of 2,600 Ma -- Granitic rocks of 2,600 Ma Granitic rocks of 2,600 Ma -- -- Major Confining Unit (Precambrian) Wgd -- -- Late Archean: granodiorite Granodiorite of the Louis Lake -- Granodiorite of the Louis Lake ------Major Confining Unit (Precambrian) Pluton Pluton WVg -- -- Middle-Late Archean: granitoid Plutonic rocks -- Plutonic rocks ------Major Confining Unit (Precambrian) Ugn -- -- Early Archean: granite gneiss & Oldest gneiss complex -- Oldest gneiss complex ------Major Confining Unit (Precambrian) migmatite Ugn+ -- -- Early Archean: granite gneiss & Early Archean granite gneiss & -- Early Archean granite gneiss and ------Major Confining Unit (Precambrian) migmatite (metagabbro) migmatite migmatite GRB, Green River Basin (structural basin); Ma, megaannum clastic: clay, silt, mud, sand, or gravel (pebble-boulder-block size) loose (unconsolidated) clastic sediment deposits or clastic sedimentary bedrock (claystone, siltstone, mudstone or shale, sandstone, conglomeratic sandstone, or conglomerate) carbonate: limestone or dolomite bedrock; formed predominantly of calcium carbonate (limestone) or calcium-magnesium carbonate (dolomite) oil shale: high-kerogen content, dolomitic claystone/marl deposited in a saline, intermontane, lacustrine environment (early Eocene Lake Gosiute); Laney Member of the

COLOR KEY Major Aquifer Minor Aquifer Marginal Aquifer Major Confining Unit (Aquitard) Unclassified Unit Modified from 2007 Wyoming Statewide Water Plan (WWC Engineering, 2007) Plate 7. Geologic units and corresponding rock-stratigraphic units, Greater Green River Basin, Wyoming, Colorado, and Utah