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Geologic Map of Alaska

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Geologic Map of Alaska Geologic Map of Alaska Compiled by Frederic H. Wilson, Chad P. Hults, Charles G. Mull, and Susan M. Karl Pamphlet to accompany Scientific Investigations Map 3340 2015 U.S. Department of the Interior U.S. Geological Survey Front cover. Color shaded relief map of Alaska and surroundings. Sources: 100-meter-resolution natural image of Alaska, http://nationalmap.gov/small_scale/mld/nate100.html; rivers and lakes dataset, http://www.asgdc.state.ak.us/; bathymetry and topography of Russia and Canada, https://www.ngdc.noaa.gov/mgg/global/global.html. Back cover. Previous geologic maps of Alaska: 1906—Brooks, A.H., Abbe, Cleveland, Jr., and Goode, R.U., 1906, The geography and geology of Alaska; a summary of existing knowledge, with a section on climate, and a topographic map and description thereof: U.S. Geological Survey Professional Paper 45, 327 p., 1 sheet. 1939—Smith, P.S., 1939, Areal geology of Alaska: U.S. Geological Survey Professional Paper 192, 100 p., 18 plates. 1957—Dutro, J.T., Jr., and Payne, T.G., 1957, Geologic map of Alaska: U.S. Geological Survey, scale 1:2,500,000. 1980—Beikman, H.M., 1980, Geologic map of Alaska: U.S. Geological Survey Special Map, scale 1:2,500,000, 2 sheets. Geologic Map of Alaska Compiled by Frederic H. Wilson, Chad P. Hults, Charles G. Mull, and Susan M. Karl Pamphlet to accompany Scientific Investigations Map 3340 2015 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Director U.S. Geological Survey, Reston, Virginia: 2015 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov/ or call 1–888–ASK–USGS (1–888–275–8747). For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod/. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Wilson, F.H., Hults, C.P., Mull, C.G., and Karl, S.M., comps., 2015, Geologic map of Alaska: U.S. Geological Survey Scientific Investigations Map 3340, 197 p., 2 sheets, scale 1:584,000, http://dx.doi.org/10.3133/sim3340. ISSN 2329-1311 (print) ISSN 2329-132X (online) ISBN 978-1-4113-4000-8 Contents Introduction ....................................................................................................................................................1 Acknowledgments ........................................................................................................................................3 Description of Map Units .............................................................................................................................5 Unconsolidated Deposits ....................................................................................................................5 Sedimentary Rocks ..............................................................................................................................5 Cenozoic to Mesozoic .................................................................................................................5 Quaternary and Tertiary ....................................................................................................5 Tertiary to Mesozoic ...........................................................................................................6 Cenozoic to Paleozoic ...............................................................................................................16 Tertiary to Devonian .........................................................................................................16 Tertiary to Jurassic .................................................................................................16 Lower Cretaceous to Devonian ............................................................................ 25 Jurassic to Mississippian ............................................................................................... 35 Triassic .............................................................................................................................. 42 Paleozoic to Proterozoic .......................................................................................................... 47 Permian to Devonian ....................................................................................................... 47 Carboniferous .................................................................................................................. 49 Devonian to Neoproterozoic .......................................................................................... 55 Silurian to Cambrian ....................................................................................................... 69 Ordovician to Proterozoic ............................................................................................... 71 Cambrian to Proterozoic ................................................................................................. 73 Proterozoic ..................................................................................................................................74 Volcanic Rocks .................................................................................................................................. 75 Cenozoic to Mesozoic .............................................................................................................. 75 Quaternary to Tertiary ..................................................................................................... 75 Tertiary to Cretaceous ..................................................................................................... 76 Mesozoic .................................................................................................................................... 82 Cretaceous to Jurassic ................................................................................................... 82 Jurassic to Triassic .......................................................................................................... 84 Triassic ............................................................................................................................... 85 Paleozoic .................................................................................................................................... 86 Permian.............................................................................................................................. 86 Carboniferous ................................................................................................................... 87 Devonian............................................................................................................................ 87 Silurian ............................................................................................................................... 88 Ordovician and Cambrian ............................................................................................... 88 Proterozoic ................................................................................................................................. 88 Intrusive Rocks ................................................................................................................................... 89 Cenozoic to Mesozoic .............................................................................................................. 89 Quaternary or Tertiary ..................................................................................................... 89 Tertiary to Cretaceous ..................................................................................................... 89 Mesozoic and Paleozoic .......................................................................................................... 96 Cretaceous to Paleozoic ................................................................................................ 96 Jurassic to Paleozoic .................................................................................................... 100 Triassic to Paleozoic ...................................................................................................... 104 Paleozoic to Proterozoic ........................................................................................................ 106 Metamorphic Rocks ....................................................................................................................... 109 iii Cenozoic to Mesozoic ............................................................................................................ 109 Quaternary or Tertiary ................................................................................................... 109 Tertiary to Mesozoic ...................................................................................................... 109 Mesozoic to Proterozoic .........................................................................................................110 Cretaceous to Paleozoic ................................................................................................110 Triassic to Proterozoic
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