Revisions: None completed or planned.
Reviews_Applied_to_Data:
Related_Spatial_and_Tabular_Data_Set: BEIKMAN.LUT (see Entity_and Attribute_Information)
Other_References_Cited: Beikman, H.M., compiler, 1980, Geologic Map of Alaska, U.S. Geological Survey. Map SG0002-1T and 2T. Scale 1:2,500,000.
Notes: The completeness and quality of the geology in the digital coverage is that of the original 1980 map. No recent data have been added. The geographic accuracy of the original published map has been slightly degraded by the rubber-sheet operation.
Map unit delineations are polygons that are generalized combinations of geologic Formations and Groups, and include both bedrock and surficial deposit units.BEIKMAN.PAT COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED? 1 AREA 4 12 F 3 - 5 PERIMETER 4 12 F 3 - 9 BEIKMAN# 4 5 B - - 13 BEIKMAN-ID 4 5 B - - 17 CODE 6 6 N - -
BEIKMAN.LUT COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED? 1 CODE 6 6 N - - 7 MAP_UNIT_ABBREV. 7 7 C - -
The item 'CODE' contains 184 unique values that represent each map unit contained in the 1980 Geologic Map of Alaska, compiled by H.M. Beikman.
Record CODE MAP_UNIT_ABBREV. 1 101 Qhvf 2 102 Tvf 3 103 TKvf 4 104 uKvf 5 105 Kvf 6 106 vf 7 201 Qhvi 8 202 Qpvi 9 203 Qvi 10 204 QTvi 11 205 Tmvi 12 206 ITvi 13 207 Tvi 14 208 IKvi 15 209 Kvi 16 210 KJvi 17 211 Jvi 18 301 Qhvm 19 302 Qpvm 20 303 Qvm 21 304 QTvm 22 305 ITvm 23 306 Tvm 24 307 TKvm 25 308 KJvm 26 309 Trvm 27 310 JPvm 28 311 MzPzvm 29 312 Pvm 30 313 Dvm 31 314 Cvm 32 315 Pzvm 33 401 Qhv 34 402 Qpv 35 403 Qv 36 404 QTv 37 405 Tpv 38 406 Tmv 39 407 uTv 40 408 Txv 41 409 ITv 42 410 Tv 43 411 TKv 44 412 IKv 45 413 Kv 46 414 KJv 47 415 Dv 48 416 Ov 49 417 Zv 50 501 Tmif 51 502 Toif 52 503 Teif 53 504 Txif 54 505 Tif 55 506 TKif 56 507 TMzif 57 508 uKif 58 509 Kif 59 510 Jif 60 511 Mzif 61 512 MzPzif 62 513 PPif 63 514 uPzif 64 515 if 65 601 mTii 66 602 Tii 67 603 TKii 68 604 uKii 69 605 Kii 70 606 KJii 71 607 Jii 72 608 JTrii 73 609 Mzii 74 610 MzPzii 75 611 Sii 76 612 Pzii 77 701 Tmim 78 702 mTim 79 703 Tim 80 704 TKim 81 705 TMzim 82 706 Kim 83 707 Jim 84 708 Mzim 85 709 Pim 86 710 PPim 87 711 uPzim 88 712 IPzim 89 713 Pzim 90 714 Zim 91 715 im 92 801 Ti 93 802 TKi 94 803 uKi 95 804 Ki 96 805 Mzi 97 806 MzPzi 98 807 PPi 99 808 Oi 100 809 Pzi 101 810 IPzpci 102 811 Pzpci 103 812 i 104 901 Tu 105 902 TKu 106 903 Ku 107 904 Mzu 108 905 JPu 109 906 MzPzu 110 907 PPu 111 908 Ou 112 909 IPzu 113 910 Pzu 114 911 u 115 1001 Q 116 1002 Qh 117 1003 Qp 118 1011 T 119 1012 mT 120 1013 uT 121 1014 IT 122 1015 Tp 123 1016 Tm 124 1017 To 125 1018 Te 126 1100 MzPz 127 1111 K 128 1112 uK 129 1113 IK 130 1121 KJ 131 1122 KJ1 132 1123 KJ2 133 1124 KJ3 134 1131 J 135 1132 uJ 136 1133 mJ 137 1134 IJ 138 1141 JP 139 1142 JM 140 1151 JTr 141 1152 Tr 142 1153 uTr 143 1154 TrP 144 1155 TrD 145 1161 P 146 1162 PPP 147 1163 PP 148 1164 PPM 149 1165 Pz 150 1166 uPz 151 1167 IPz 152 1171 M 153 1172 MD 154 1173 D 155 1174 uD 156 1175 umD 157 1176 DS 158 1181 S 159 1182 O 160 1183 SO 161 1184 C 162 1185 OpC 163 1191 IPzpC 164 1192 Z 165 1193 Z1 166 1194 Z2 167 1211 Tpc 168 1212 uTc 169 1221 Tmc 170 1222 mTc 171 1223 ITc 172 1224 Txc 173 1225 Tc 174 1226 TKc 175 1231 uKc 176 1232 IKc 177 1311 IJm 178 1321 Mzm 179 1322 JPm 180 1331 Pzm 181 1341 PzpCm 182 1411 white 183 1511 Ice 184 1611 water
These are the geologic unit descriptions from Beikman, H.M., 1980, Geologic map of Alaska: U.S. Geological Survey Special Map, scale 1:2,500,000, 2 sheets. The numeric CODE used in the digital coverage precedes the geologic unit label.
STRATIFIED SEDIMENTARY SEQUENCE Mainly marine. Includes some volcanic rocks. In part metamorphosed 1002 Qh HOLOCENE DEPOSITS - Alluvial, glacial, lake, estuarine, swamp, landslide, flood plain, and beach deposits 1001 Q QUATERNARY DEPOSITS - Alluvial, glacial, lake, eolian, beach, and volcanic deposits. Includes the marine Bootlegger Cove Clay 1003 Qp PLEISTOCENE DEPOSITS - Alluvial, glacial, dune sand, loess, and reworked sand and silt deposits 1015 Tp PLIOCENE ROCKS - Sandstone, siltstone, and conglomerate. Includes Tachilni Formation on the Alaska Peninsula and Tugidak Formation on Tugidak and Chirikof Islands 1013 uT UPPER TERTIARY ROCKS - Sandstone, siltstone, shale, mudstone, and conglomerate of Miocene and Pliocene age. Includes upper part of the Sagavanirktok Formation on the Arctic Coastal Plain, and the Yakataga Formation in the Gulf of Alaska area 1016 Tm MIOCENE ROCKS - Sandstone, siltstone, conglomerate, argillite, graywacke, and basaltic rocks. As shown, includes Bear Lake Formation on the Alaska Peninsula, Narrow Cape Formation (Oligocene or Miocene) on Kodiak and Sitkinak Islands, and Chuniksak Formation (Miocene?) on Attu Island 1017 To OLIGOCENE ROCKS - Volcanic conglomerate, sandstone, volcanic breccia, shale, and siltstone. As shown, includes the Meshik Formation and Stepovak Formation of Burk (1965) on the Alaska Peninsula and the Sitkinak Formation on Sitkalidak, Sitkinak, and Chirikof Islands 1018 Te EOCENE ROCKS - Sandstone, siltstone, and shale interbedded with mafic flows and sills of the Andrew Lake Formation on Adak Island 1011 T TERTIARY ROCKS - Sedimentary rocks concealed beneath Quaternary cover on Point Hope and volcanogenic sedimentary rocks and flows, dikes, and sills on the Alaska Peninsula and Umnak Island 1012 mT MIDDLE TERTIARY ROCKS - Siltstone, sandstone, organic shale, and locally, volcanic rocks. Includes Poul Creek, Katalla, and Topsy Formations ranging from Oligocene to Miocene age in Gulf of Alaska area 1014 lT LOWER TERTIARY ROCKS - Interbedded sedimentary, volcanogenic, and volcanic rocks of Paleocene, Eocene, and Oligocene age on the Alaska Peninsula and Aleutian Islands and intensely deformed marine and continental clastic rocks of Paleocene and Eocene age in the Gulf of Alaska area. Includes the Tolstoi and Belkofski Formations of Burk (1965) in the Alaska Peninsula; the Ghost Rocks Formation on Kodiak Island; the Amchitka and Banjo Point Formations on Amchitka Island; Gunners Cove Formation on Rat Island; the Krugloi Formation on Agattu Island; and Kulthieth, Kushtaka, and Tokun Formations and clastic rocks of the Orca Group in the Gulf of Alaska area 1112 uK UPPER CRETACEOUS ROCKS - Shale, sandstone, and conglomerate of the Ninuluk Formation of the Nanushuk Group and the Seabee and Schrader Bluff Formations of the Colville Group in the Arctic Coastal Plain and Foothills; nonmarine and marine clastic rocks, siltstone, and shale of the Chignik and Hoodoo Formations on the Alaska Peninsula; graded beds of sandstone and slate of the Kodiak Formation on Kodiak and Afgonak Islands; sandstone and mudstone of Shumagin Formation on Shumagin and Sanak Islands 1111 K CRETACEOUS ROCKS - Volcanic graywacke, mudstone, and sandstone with some coal-bearing rocks in the Yukon-Koyukuk province; graywacke and shale of the Kuskokwim Group in the Kuskokwim Mountains; and shelf deposits of sandstone, siltstone, shale and limestone of the Kennicott, Moonshine Creek, Schulze, Chititu, and MacColl Ridge Formations in the southern Wrangell Mountains; the Matanuska Formation in the Matanuska Valley; and the Kaguyak Formation on the Alaska Peninsula 1113 lK LOWER CRETACEOUS ROCKS - Graywacke, sandstone, shale, siltstone, and conglomerate of part of the Tiglukpuk Formation of former usage, Okpikruak, Fortress Mountain, Torok, and Kukpowruk Formations in the western Arctic Foothills; the Kongakut Formation, Bathtub Graywacke, and Tuktu and Grandstand Formations in the eastern Brooks Range and Arctic Foothills; unnamed graywacke, argillite, conglomerate, and minor limestone southeast of the mouth of the Kuskokwim River; interlayered submarine and subaerial andesitic fragmental volcanic rocks, flows, tuffs, and volcaniclastic rocks of the Chisana Formation north of the Wrangell Mountains; and unnamed graywacke, argillite, and minor andesite on Etolin Island 1121 KJ CRETACEOUS AND JURASSIC ROCKS - Argillite, shale, graywacke, quartzite, conglomerate, lava, tuff, and agglomerate. Almost barren of fossils and probably includes rocks ranging in age from Early Jurassic to Late Cretaceous. In places moderately to highly metamorphosed (amphibolite facies) 1122 KJ1 CRETACEOUS AND UPPER JURASSIC ROCKS - Graywacke, slate, argillite, minor conglomerate, volcanic detritus, and interbedded mafic volcanic rocks. Includes Valdez and part of Yakutat Groups and Sitka Graywacke. Mildly metamorphosed, locally to greenschist 1123 KJ2 LOWER CRETACEOUS AND UPPER JURASSIC ROCKS - Shallow and deep water clastic deposits (Oxfordian to Barremian) north of the Wrangell Mountains; includes sandstone, arkose, siltstone, and limestone of the Staniukovich Formation (Burk, 1965) and Herendeen Limestone on the Alaska Peninsula; and slate, graywacke and conglomerate of the Seymour Canal Formation on Admiralty and Kupreanof Islands 1124 KJ3 LOWER CRETACEOUS AND UPPER JURASSIC(?) ROCKS- Melange of flysch, greenstone, limestone, chert, granodiorite, glaucophane-bearing greenschist, and layered gabbro and serpentinite. Melange consists of Upper Jurassic(?) and Lower Cretaceous pelitic matrix enclosing blocks several kilometers in dimension of Permian to Lower Jurassic rocks. Includes the Uyak Formation, McHugh Complex, melange within the Yakutat Group, and Waterfall Greenstone and Khaz Formation of the Kelp Bay Group 1132 uJ UPPER JURASSIC ROCKS - Sandstone, siltstone, shale, and conglomerate on the Alaska Peninsula, Cook Inlet area, and southern flank of the Talkeetna Mountains. Includes the Chinitna and Naknek Formations 1133 mJ MIDDLE JURASSIC ROCKS - Argillite, graywacke, and conglomerate southeast of the Kuskokwim River and sandstone, shale, siltstone, and conglomerate on the Alaska Peninsula and Cook Inlet area where it includes the Kialagvik and Shelikof Formations and Tuxedni Group 1134 lJ LOWER JURASSIC ROCKS - Sandstone and argillite interbedded with volcanic flows and pyroclastic rocks of the Talkeetna Formation in the Cook Inlet area and southern Talkeetna Mountains 1131 J JURASSIC ROCKS - Shale, siltstone, and sandstone. Includes the Kingak Shale along the northern front of the Brooks Range, Glenn Shale (which includes rocks of Triassic and Cretaceous age) in the east-central part of the State, the Nizina Mountain Formation and Kotsina Conglomerate along the southern Wrangell Mountains, and unnamed slaty detrital rocks on Gravina and Annette Islands 1151 JTR JURASSIC AND(OR) TRIASSIC ROCKS - Chert and argillite north of the Porcupine River; limestone with minor dolomite, shale, and chert of the Chitistone Limestone, Nizina Limestone, McCarthy Formation, and Lubbe Creek Formation along the southern Wrangell Mountains; and hornfels and phyllite of the Hazelton(?) Group in southeast Alaska 1153 uTR UPPER TRIASSIC ROCKS - Limestone, shale, and chert of the Kamishak Formation in the Cook Inlet area; a shelf facies of limestone, tuff, tuffaceous conglomerate and breccias at the southern tip of the Kenai Peninsula (west of the Border Ranges fault) and equivalent rocks on Shuyak, Afognak, and Kodiak Islands; a deep water flysch and melange facies of chert, pillow basalt and associated graywacke, argillite, and minor ultramafic rocks (east of the Border Ranges fault) on the southern Kenai Peninsula; chert, limestone, sandstone, and greenstone of the Whitestripe Marble and Pinnacle Peak Phyllite (both Triassic?) on Chichagof and Baranof Islands, of the Hyd Group on Admiralty Island and Keku Straits area, and of the Nehenta and Chapin Peak Formations on Gravina Island 1152 TR TRIASSIC ROCKS - Shale, chert, and limestone of the Shublik Formation and quartzitic sandstone of the Karen Creek Sandstone on the north flank of the Brooks Range 1154 TRP TRIASSIC AND PERMIAN ROCKS - Sandstone, siltstone, and shale of the Sadlerochit Group on the north flank of the Brooks Range; mafic volcanic rocks, red beds, limestone, and calcareous argillite in the Chulitna River area; argillite, limestone, siltstone, conglomerate, and abundant gabbroic sills in the east-central Alaska Range where it includes the upper part of the Mankomen Group; and schist, graywacke, slate, conglomerate, phyllite, andesite flows and tuffs on Admiralty Island where it includes the Barlow Cove Formation 1141 JP JURASSIC, TRIASSIC, AND PERMIAN ROCKS - Shale, siltstone, and chert, and graywacke in the Brooks Range. Includes upper part of Nuka Formation and Siksikpuk and Shublik Formations 1100 MzPz MESOZOIC AND PALEOZOIC ROCKS - Sandstone, shale, chert, dolomite and conglomerate, in a discordant rock sequence of unknown provenance that includes rocks of Mississippian, Triassic, Jurassic, and Cretaceous age in the western Brooks Range (includes Nuka Formation); Lower Jurassic, Pennsylvanian, and Permian rocks, in part covered by Tertiary sedimentary rocks and intruded by granitic rocks of Tertiary age in north-central Chugach Mountains: and slate, quartzite, schist and phyllite with interlayered beds of marble, layered gneiss and amphibolite of Ordovician to Jurassic or Cretaceous age along the west flank of the Coast Mountains 1161 P PERMIAN ROCKS - Chert, shale, and siltstone of the Siksikpuk and Echooka Formations in the central Arctic Foothills and volcanic argillite and graywacke with local chert, pillow flows, limestone, and dolomite of the Cannery, Pybus, and Halleck Formations on Admiralty, Kuiu, and Kupreanof Islands 1162 PIP PERMIAN AND PENNSYLVANIAN ROCKS - Basaltic to andesitic lavas and derivative volcaniclastic rocks, tuffs, minor gabbro, and local shallow-water sedimentary rocks metamorphosed to greenschist facies, and locally, amphibolite facies. Includes Skolal Group, Strelna Formation (Permian), and Tetelna Volcanics in the Wrangell and Talkeetna Mountains. Consists of unnamed phyllite, slate, schist, greenschist, amphibolite, gneiss, and migmatite in St. Elias Mountains
1163 IP PENNSYLVANIAN ROCKS - Siltstone, sandstone, and limestone of the Klawak Formation and Ladrones Limestone on Prince of Wales Island 1164 IPM PENNSYLVANIAN AND MISSISSIPPIAN ROCKS - Limestone, conglomerate, shale, dolomite, and chert of the Kekiktuk Conglomerate and Kayak Shale (both of Mississippian age) of the Endicott Group and the Alapah and Wahoo Limestones of the Lisburne Group
1171 M MISSISSIPPIAN ROCKS - Conglomerate, shale, limestone with subordinate chert and dolomite of the Kekiktuk Conglomerate and Kayak Shale of the Endicott Group and the Utukok Formation and Wachsmuth and Alapah Limestones of the Lisburne Group on the northern flank of the Brooks Range. Limestone, dolomite, and inter- bedded chert of the Iyoukeen Formation on Chichagof Island and Peratrovich Formation on Prince of Wales Island 1142 JM JURASSIC TO MISSISSIPPIAN ROCKS - Unnamed slate and quartzite northwest of Porcupine River and Lisburne and Sadlerochit Groups and Kingak Shale at northeast front of Brooks Range 1155 TRD TRIASSIC TO DEVONIAN ROCKS - Radiolarian chert, slate, and argillite 1166 uPz UPPER PALEOZOIC ROCKS - Argillite, chert, shale, limestone, and siltstone. Greenstone, limestone, shale, clastic sedimentary rocks, schist, gneiss, and undifferentiated metamorphic rocks east of Juneau 1165 Pz PALEOZOIC ROCKS - Limestone, marble, dolomite, and chert on Seward Peninsula and St. Lawrence Island; limestone, slate, and conglomerate in central Alaska Range; argillite and graywacke slightly metamorphosed west of Chulitna River; flysch, conglomerate, limestone and pillow basalt southwest of Mount McKinley; marble, in places containing tremolite in Wrangell Mountains where it includes parts of a Devonian section designated the Kaskawulsh Group in the Yukon Territory (Canada); and sedimentary, metasedimentary, and metavolcanic rocks in southeastern Alaska 1172 MD MISSISSIPPIAN AND(OR) DEVONIAN ROCKS - Sandstone, graywacke, quartzite, and conglomerate. Includes the Noatak Sandstone in western Brooks Range and Kekiktuk and Kanayut Conglomerates in eastern Brooks Range 1173 D DEVONIAN ROCKS - PhyIlite, hornfels, graywacke, and sandstone on the Seward Peninsula; pyroclastic rocks and ash flows interbedded with sedimentary rocks metamorphosed to schist and gneiss on north- central flank of Alaska Range; limestone east of Kuskokwim Bay; clastic rocks and limestone of the Kennel Creek Limestone (which may also include Silurian rocks) and Cedar Cove Formation on Chichagof Island; schist, phyllite, marble, and amphibolite of the Retreat Group and Gambler Bay Formation on Admiralty and Kupreanof Islands and equivalent rocks to the north and south; and limestone, shale, graywacke, conglomerate and basaltic rocks of the St. Joseph Island Volcanics (Devonian?), Wadleigh Limestone, and Port Refugio Formation on Prince of Wales Island 1174 uD UPPER DEVONIAN ROCKS - Shale, sandstone, chert, conglomerate, and quartzite in eastern and central Brooks Range and limestone and dolomite in western Brooks Range. Includes Hunt Fork Shale, Kanayut Conglomerate, Kugururok Formation, and Eli Limestone (Middle and Upper Devonian) 1175 umD UPPER AND(OR) MIDDLE DEVONIAN ROCKS - Conglomerate, graywacke, phyllite, shale, sandstone, siltstone, and limestone. Includes Nanook Limestone in Shublik Mountains 1176 DS DEVONIAN AND SILURIAN ROCKS - Limestone, dolomite, marble, and shale of the Katakturuk Dolomite and the Skajit Limestone in Brooks Range and Karheen Formation in Prince of Wales Island 1181 S SILURIAN ROCKS - Graywacke, shale, siltstone, limestone, sandstone, and argillite. Includes siltstone, mudstone, limestone, conglomerate, sandstone, graywacke, minor red beds and volcanic rocks of the Rendu Formation, and Willoughby Limestone in Glacier Bay area; the Point Augusta Formation on Chichagof Island; Bay of Pillars Formation on Admiralty, Kuiu, and Prince of Wales Islands; and Kuiu Limestone and Heceta Limestone on Prince of Wales Island 1182 O ORDOVICIAN ROCKS - Limestone and shale on Seward Peninsula; argillite, chert and limestone of the Hood Bay Formation on Admiralty Island 1183 SO SILURIAN AND ORDOVICIAN ROCKS - Graywacke, conglomerate, shale, siltstone, tuff, lava, and local limestone of the Descon Formation on Prince of Wales Island 1184 C CAMBRIAN ROCKS - Siltstone, sandstone, and phyllite 1185 OpC ORDOVICIAN, CAMBRIAN, AND PRECAMBRIAN ROCKS - Phyllite, sandstone; siltstone, limestone, chert, and quartzite 1167 lPz LOWER PALEOZOIC ROCKS - Includes rocks of Cambrian through Devonian age, in places metamorphosed to greenschist and amphibolite facies. Sedimentary rocks include limestone, dolomite, argillite, chert, and graywacke and metasedimentary rocks include schist, quartzite, slate, greenstone, carbonate rocks, and phyllite. Includes Holitna Group in Kuskokwim Mountains, Tonzona Group along Kuskokwim River, rocks formerly included in Birch Creek Schist in Yukon-Tanana Upland, unmetamorphosed rocks of the Funnel Creek, Adams, Hillard, Road River, McCann Hill and Hillard Formations, and Puppets Formation on Gravina and Annette Islands 1191 lPzpC LOWER PALEOZOIC AND(OR) PRECAMBRIAN ROCKS - Sandstone, limestone, shale, chert, phyllite, argillite, and quartzite of the Neruokpuk Formation in the northeast Brooks Range; quartz-mica schist, mafic greenschist, calcareous schist, chloritic schist, phyllite and quartzite along south flank of Brooks Range and southwest through Kokrine-Hodzana Highlands; schist and quartzite of the Birch Creek Schist of former usage in Yukon-Tanana Highlands; highly metamorphosed clastic rocks including the Keevy Peak Formation in the north flank of Brooks Range; and volcanogenic greenschist with interstratified marble in Prince of Wales, Long and Dall Islands, where it includes the Wales Group and possibly Descon Formation 1192 Z PRECAMBRIAN Z ROCKS - Siltite, phyllite, graywacke, quartz schist, and graphitic schist of slate of the York region on Seward Peninsula; schist, gneiss, and small amounts of amphibolite and marble east of Kuskokwim Bay; quartz wacke, semi-schist, phyllite, and argillite of the Neruokpuk Formation in northeastern Brooks Range; phyllite, slate, and siltstone east of Fort Yukon; and limestone, dolomite, sandstone, shale, and basalt of the Tindir Group north of Tintina fault 1193 Z1 YOUNGER PRECAMBRIAN Z ROCKS - Schistose, argillaceous, dolomitic limestone and tactite on Seward Peninsula 1194 Z2 OLDER PRECAMBRIAN Z ROCKS - Schist, gneiss, and migmatic and metamorphic rocks, including rocks equivalent to slate of the York region, in the Kigluaik and Bendeleben Mountains on the Seward Peninsula
CONTINENTAL DEPOSITS 1211 Tpc PLIOCENE CONTINENTAL DEPOSITS - Pebble to boulder conglomerate, coarse sandstone, siltstone, claystone, and thin lignite beds. Includes Nenana Gravel (Pliocene?) 1212 uTc UPPER TERTIARY CONTINENTAL DEPOSITS - Sandstone, siltstone, claystone, minor conglomerate, and coal beds. Includes upper part of Kenai Group in Cook Inlet area and Nenana Gravel and related unnamed rocks in west-central Alaska Range. Rocks range in age from Oligocene(?) through Pliocene 1221 Tmc MIOCENE CONTINENTAL DEPOSITS - Sandstone, siltstone, shale, claystone, conglomerate, and coal beds. Includes the Sanctuary, Suntrana, Grubstake, and Lignite Creek Formations in central Alaska Range and the Frederika Formation in Wrangell Mountains 1222 mTc MIDDLE TERTIARY CONTINENTAL DEPOSITS - Sandstone, siltstone, claystone and coal beds. Includes the Healy Creek Formation in central Alaska Range, the Gakona Formation in east-central Alaska Range, and the Tsadaka Formation in Matanuska Valley. Rocks range in age from Oligocene through Miocene 1223 lTc LOWER TERTIARY CONTINENTAL DEPOSITS - Claystone, siltstone, sandstone, conglomerate, and coal beds. Includes lower part of Sagavanirktok Formation in the Arctic Coastal Plain and the Chickaloon and Wishbone Formations in the Matanuska Valley. Rocks range in age from Paleocene through Oligocene 1224 Txc PALEOCENE CONTINENTAL DEPOSITS - Conglomerate, sandstone, coaly shale, and shale. Includes Cantwell Formation in central Alaska Range 1225 Tc TERTIARY CONTINENTAL DEPOSITS - Sandstone, coal, conglomerate and shale of the Kootznahoo Formation on Admiralty, Kuiu, Kupreanof, and Zarembo Islands 1226 TKc TERTIARY AND CRETACEOUS CONTINENTAL DEPOSITS - Conglomerate, breccia, sandstone, arkose, mudstone, shale, tuffaceous rocks, and lignite. Includes Arkose Ridge Formation (Cretaceous?) in Matanuska Valley 1231 uKc UPPER CRETACEOUS CONTINENTAL DEPOSITS - Sandstone and conglomerate and interbedded shale, clay, silt, and bentonite of the Niakogon Tongue of the Chandler Formation of the Nanushuk Group and the Prince Creek Formation of the Colville Group on the Arctic Coastal Plain; shale and siltstone in the Yukon-Koyukuk basin; and pebble conglomerate around the margins of the basin 1232 lKc LOWER CRETACEOUS CONTINENTAL DEPOSITS - Shale, claystone, siltstone, sandstone, conglomerate, coaly shale and coal, ironstone, and bentonite. Includes Corwin Formation (Lower and Upper Cretaceous) of Nanushuk Group and Killik Tongue of Chandler Formation of Nanushuk Group on Arctic Coastal Plain
METAMORPHIC ROCKS 1311 lJm LOWER JURASSIC METAMORPHIC ROCKS - Intercalated blueschist, quartz mica schist, greenschist with subordinate amphibolite, marble, and metachert at southern tip of Kenai Peninsula and on Afognak Island 1321 Mzm MESOZOIC METAMORPHIC ROCKS - Small masses of metamorphosed sedimentary, volcanic, and igneous rocks, largely of pre-Cretaceous age, scattered throughout the Aleutian Range batholith. Amphibolite facies schist along north side of Matanuska Valley 1322 JPm JURASSIC, TRIASSIC, AND PERMIAN METAMORPHIC ROCKS - Metasedimentary, metaplutonic,and metavolcanic rocks near Anchorage and along south side of Matanuska Valley 1331 Pzm PALEOZOIC METAMORPHIC ROCKS - Hornfels, schist, amphibolite, minor marble, and undivided metamorphic rocks north of Icy Strait in southeastern Alaska, and gneiss, schist, phyllite, and undifferentiated metasedimentary and metaigneous rocks in the Yukon- Tanana Upland 1341 PzpCm PALEOZOIC AND(OR) PRECAMBRIAN METAMORPHIC ROCKS - Metasedimentary and metaigneous rocks, including schist and gneiss of many different compositions, primarily of the greenschist and amphibolite fades, in the Yukon-Tanana Upland. Formerly included in the Birch Creek Schist
VOLCANIC ROCKS
101 Qhvf HOLOCENE FELSIC VOLCANIC ROCKS - Rhyolite to dacite 201 Qhvi HOLOCENE INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 301 Qhvm HOLOCENE MAFIC VOLCANIC ROCKS - Basalt 401 Qhv HOLOCENE UNDIFFERENTIATED VOLCANIC ROCKS 202 Qpvi PLEISTOCENE INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 302 Qpvm PLEISTOCENE MAFIC VOLCANIC ROCKS - Basalt 402 Qpv PLEISTOCENE UNDIFFERENTIATED VOLCANIC ROCKS 203 Qvi QUATERNARY INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 303 Qvm QUATERNARY MAFIC VOLCANIC ROCKS - Basalt 403 Qv QUATERNARY UNDIFFERENTIATED VOLCANIC ROCKS 204 QTvi QUATERNARY OR TERTIARY INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 304 QTvm QUATERNARY OR TERTIARY MAFIC VOLCANIC ROCKS - Basalt 404 QTv QUATERNARY OR TERTIARY UNDIFFERENTIATED VOLCANIC ROCKS 405 Tpv PLIOCENE UNDIFFERENTIATED VOLCANIC ROCKS 205 Tmvi MIOCENE INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 406 Tmv MIOCENE UNDIFFERENTIATED VOLCANIC ROCKS 407 uTv UPPER TERTIARY UNDIFFERENTIATED VOLCANIC ROCKS 408 Txv PALEOCENE UNDIFFERENTIATED VOLCANIC ROCKS 206 lTvi LOWER TERTIARY INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 305 lTvm LOWER TERTIARY MAFIC VOLCANIC ROCKS - Basalt 409 lTv LOWER TERTIARY UNDIFFERENTIATED ROCKS 102 Tvf TERTIARY FELSIC VOLCANIC ROCKS - Rhyolite to dacite 207 Tvi TERTIARY INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 306 Tvm TERTIARY MAFIC VOLCANIC ROCKS - Basalt 410 Tv TERTIARY UNDIFFERENTIATED VOLCANIC ROCKS 103 TKvf TERTIARY AND(OR) CRETACEOUS FELSIC VOLCANIC ROCKS - Rhyolite to dacite 307 TKvm TERTIARY AND(OR) CRETACEOUS MAFIC VOLCANIC ROCKS - Basalt 411 TKv TERTIARY AND(OR) CRETACEOUS UNDIFFERENTIATED VOLCANIC ROCKS 104 uKvf UPPER CRETACEOUS FELSIC VOLCANIC ROCKS - Rhyolite to dacite 208 lKvi LOWER CRETACEOUS INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 412 lKv LOWER CRETACEOUS UNDIFFERENTIATED VOLCANIC ROCKS 105 Kvf CRETACEOUS FELSIC VOLCANIC ROCKS - Rhyolite to dacite 209 Kvi CRETACEOUS INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 413 Kv CRETACEOUS UNDIFFERENTIATED VOLCANIC ROCKS 210 KJvi CRETACEOUS AND(OR) JURASSIC INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 308 KJvm CRETACEOUS AND(OR) JURASSIC MAFIC VOLCANIC ROCKS - Basalt 414 KJv CRETACEOUS AND(OR) JURASSIC UNDIFFERENTIATED VOLCANIC ROCKS 211 Jvi JURASSIC INTERMEDIATE VOLCANIC ROCKS - Trachyte to andesite 309 TRvm TRIASSIC MAFIC VOLCANIC ROCKS - Basalt 310 JPvm JURASSIC, TRIASSIC, AND PERMIAN MAFIC VOLCANIC ROCKS - Basalt 311 MzPzvm PALEOZOIC AND MESOZOIC MAFIC VOLCANIC ROCKS - Basalt 312 Pvm PERMIAN MAFIC VOLCANIC ROCKS - Basalt 313 Dvm DEVONIAN MAFIC VOLCANIC ROCKS - Basalt 415 Dv DEVONIAN UNDIFFERENTIATED VOLCANIC ROCKS 416 Ov ORDOVICIAN UNDIFFERENTIATED VOLCANIC ROCKS 314 Cvm CAMBRIAN MAFIC VOLCANIC ROCKS - Basalt 315 Pzvm PALEOZOIC MAFIC VOLCANIC ROCKS - Basalt 417 Zv PRECAMBRIAN Z UNDIFFERENTIATED VOLCANIC ROCKS 106 vf FELSIC VOLCANIC ROCKS, AGE UNKNOWN - Rhyolite to dacite
INTRUSIVE ROCKS 501 Tmif MIOCENE FELSIC INTRUSIVE ROCKS - Granite to granodiorite 701 Tmim MIOCENE MAFIC INTRUSIVE ROCKS - Gabbro 502 Toif OLIGOCENE FELSIC INTRUSIVE ROCKS - Granite to granodiorite 601 mTii MIDDLE TERTIARY INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 702 mTim MIDDLE TERTIARY INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 503 Teif EOCENE FELSIC INTRUSIVE ROCKS - Granite to granodiorite 504 Txif PALEOCENE FELSIC INTRUSIVE ROCKS - Granite to granodiorite 505 Tif TERTIARY FELSIC INTRUSIVE ROCKS - Granite to granodiorite 602 Tii TERTIARY INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 703 Tim TERTIARY MAFIC INTRUSIVE ROCKS - Gabbro 801 Ti TERTIARY UNDIFFERENTIATED INTRUSIVE ROCKS 506 TKif TERTIARY AND(OR) CRETACEOUS FELSIC INTRUSIVE ROCKS - Granite to granodiorite 603 TKii TERTIARY AND(OR) CRETACEOUS INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 704 TKim TERTIARY AND(OR) CRETACEOUS MAFIC INTRUSIVE ROCKS - Gabbro 802 TKi TERTIARY AND(OR) CRETACEOUS UNDIFFERENTIATED INTRUSIVE ROCKS 507 TMzif TERTIARY AND(OR) MESOZOIC FELSIC INTRUSIVE ROCKS - Granite to granodiorite 705 TMzim TERTIARY AND(OR) MESOZOIC MAFIC INTRUSIVE ROCKS - Gabbro 508 uKif UPPER CRETACEOUS FELSIC INTRUSIVE ROCKS - Granite to granodiorite 604 uKii UPPER CRETACEOUS INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 803 uKi UPPER CRETACEOUS UNDIFFERENTIATED INTRUSIVE ROCKS 509 Kif CRETACEOUS FELSIC INTRUSIVE ROCKS - Granite to granodiorite 605 Kii CRETACEOUS INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 706 Kim CRETACEOUS MAFIC INTRUSIVE ROCKS - Gabbro 804 Ki CRETACEOUS UNDIFFERENTIATED ROCKS 606 KJii CRETACEOUS AND(OR) JURASSIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 510 Jif JURASSIC FELSIC INTRUSIVE ROCKS - Granite to granodiorite 607 Jii JURASSIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 707 Jim JURASSIC MAFIC INTRUSIVE ROCKS - Gabbro 608 JTRii JURASSIC AND(OR) TRIASSIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 511 Mzif MESOZOIC FELSIC INTRUSIVE ROCKS - Granite to granodiorite 609 Mzii MESOZOIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 708 Mzim MESOZOIC MAFIC INTRUSIVE ROCKS - Gabbro 805 Mzi MESOZOIC UNDIFFERENTIATED INTRUSIVE ROCKS 512 MzPzif MESOZOIC AND PALEOZOIC FELSIC INTRUSIVE ROCKS - Granite to granodiorite 610 MzPzii MESOZOIC AND PALEOZOIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 806 MzPzi MESOZOIC AND PALEOZOIC UNDIFFERENTIATED INTRUSIVE ROCKS 709 Pim PERMIAN MAFIC INTRUSIVE ROCKS - Gabbro 513 IPif PENNSYLVANIAN FELSIC INTRUSIVE ROCKS - Granite to granodiorite 710 IPim PENNSYLVANIAN MAFIC INTRUSIVE ROCKS - Gabbro 807 IPi PENNSYLVANIAN UNDIFFERENTIATED INTRUSIVE ROCKS 514 uPzif UPPER PALEOZOIC FELSIC INTRUSIVE ROCKS - Granite to granodiorite 711 uPzim UPPER PALEOZOIC MAFIC INTRUSIVE ROCKS - Gabbro 611 Sii SILURIAN INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 808 Oi ORDOVICIAN UNDIFFERENTIATED INTRUSIVE ROCKS 712 lPzim LOWER PALEOZOIC MAFIC INTRUSIVE ROCKS - Gabbro 612 Pzii PALEOZOIC INTERMEDIATE INTRUSIVE ROCKS - Syenite to diorite 713 Pzim PALEOZOIC MAFIC INTRUSIVE ROCKS - Gabbro 809 Pzi PALEOZOIC UNDIFFERENTIATED INTRUSIVE ROCKS 810 lPzpCi LOWER PALEOZOIC AND(OR) PRECAMBRIAN UNDIFFERENTIATED INTRUSIVE ROCKS 811 PzpCi PALEOZOIC AND(OR) PRECAMBRIAN UNDIFFERENTIATED INTRUSIVE ROCKS 714 Zim PRECAMBRIAN Z MAFIC INTRUSIVE ROCKS - Gabbro 515 if FELSIC INTRUSIVE ROCKS, AGE UNKNOWN - Granite to granodiorite 715 im MAFIC INTRUSIVE ROCKS, AGE UNKNOWN - Gabbro 812 i UNDIFFERENTIATED INTRUSIVE ROCKS, AGE UNKNOWN
ULTRAMAFIC ROCKS 901 Tu TERTIARY ULTRAMAFIC ROCKS 902 TKu TERTIARY AND(OR) CRETACEOUS ULTRAMAFIC ROCKS 903 Ku CRETACEOUS ULTRAMAFIC ROCKS 904 Mzu MESOZOIC ULTRAMAFIC ROCKS 905 JPu JURASSIC, TRIASSIC, AND PERMIAN ULTRAMAFIC ROCKS 906 MzPzu MESOZOIC AND PALEOZOIC ULTRAMAFIC ROCKS 907 IPu PENNSYLVANIAN ULTRAMAFIC ROCKS 908 Ou ORDOVICIAN ULTRAMAFIC ROCKS 909 lPzu LOWER PALEOZOIC ULTRAMAFIC ROCKS 910 Pzu PALEOZOIC ULTRAMAFIC ROCKS 911 u ULTRAMAFIC ROCKS, AGE UNKNOWN
Although these data have been processed successfully on a computer system at the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the Geological Survey regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. The U.S. Dept. of Interior, nor any of its agencies are liable for misuse of the data, nor for any damage, transmission of viruses or computer contamination caused through transmission of these data sets.