Geologic Map of IDAHO 2012 COMPILED BY Reed S. Lewis, Paul K. Link, Loudon R. Stanford, and Sean P. Long Geologic Map of Idaho Compiled by Reed S. Lewis, Paul K. Link, Loudon R. Stanford, and Sean P. Long Idaho Geological Survey Geologic Map 9 Third Floor, Morrill Hall 2012 University of Idaho Front cover photo: Oblique aerial Moscow, Idaho 83843-3014 view of Sand Butte, a maar crater, northeast of Richfield, Lincoln County. Photograph Ronald Greeley. Geologic Map Idaho Compiled by Reed S. Lewis, Paul K. Link, Loudon R. Stanford, and Sean P. Long 2012 INTRODUCTION The Geologic Map of Idaho brings together the ex- Map units from the various sources were condensed tensive mapping and associated research released since to 74 units statewide, and major faults were identified. the previous statewide compilation by Bond (1978). The Compilation was at 1:500,000 scale. R.S. Lewis com- geology is compiled from more than ninety map sources piled the northern and western parts of the state. P.K. (Figure 1). Mapping from the 1980s includes work from Link initially compiled the eastern and southeastern the U.S. Geological Survey Conterminous U.S. Mineral parts and was later assisted by S.P. Long. County geo- Appraisal Program (Worl and others, 1991; Fisher and logic maps were derived from this compilation for the others, 1992). Mapping from the 1990s includes work Digital Atlas of Idaho (Link and Lewis, 2002). Follow- by the U.S. Geological Survey during mineral assess- ments of the Payette and Salmon National forests (Ev- ing the county map project, the statewide compilation ans and Green, 2003; Lund, 2004). In the late 1990s, was updated, scanned, and digitized at the Idaho Geo- the Idaho Geological Survey began completing the logical Survey. A 1:750,000-scale base derived from mapping within 30’ x 60’ quadrangles, mostly at a scale 10-meter digital elevation models was prepared for the of 1:24,000, with funding in part by the U.S. Geologi- new map. All surficial unit contacts were modified by cal Survey Statemap Program (e.g., Lewis and others L.R. Stanford to reflect the detail of the shaded-relief 2001, 2002, 2005, 2008; Kauffman and others, 2005, base map. In addition to the map, representative strati- 2009). Since the late 1990s, about 30 percent of the state graphic columns were constructed for six areas of the has been mapped, and this work is ongoing. Numerous state (Figures 2­‑6). thesis projects during the past three decades have also provided local detail. Idaho Geological Survey Geologic Map 9 Idaho Geological Survey Geologic Map 9 64 65 Index sources of geologic mapping (Figure 1 continued). 37 1. Armstrong and others, 1978 51. Link and Stanford, 1999 2. Benford and others, 2010 52. Long and Link, 2007 3. Blake, 1991 53. Lonn and others, 2008 4. Bond, 1978 (entire state) 54. Lund, 2004 36 43 5. Bond and others, 2011 55. Lund and others, 1993 6. Bonnichsen and Godchaux, 2006 56. Lund and others, 1983 7. Breckenridge and Othberg, 2006b 57. Malde and others, 1963 8. Breckenridge and Othberg, 2006a 58. Manduca and others, 1993 39 40 9. Christiansen, 2001 59. Mansfield, 1929 10. Christiansen and Wahl, 1999 60. Mansfield and Girty, 1927 11. Clemens, 1990 61. McIntyre, 1976 12. Cooley and Pederson, 2010 62. Michalek, 2010 42 41 13. Ekren and others, 1981 63. Miller, 1983 47 14. Evans and Green, 2003 64. Miller and Burmester, 2004 15. Fisher and others, 1992 65. Miller and others, 1999 16. Fitzgerald, 1982 66. O'Neill and Christiansen, 2004 26 38 46 17. Foord and others, 1987 67. Oriel, 1968 95 18. Gray and Oldow, 2005 68. Oriel and Moore, 1985 19. Gualtieri and Simmons, 2007 69. Oriel and Platt, 1980 48 20. Hladky and others, 1992 70. Othberg, 1982 35 21. Howard and others, 1982 71. Othberg, 1984 45 56 99 19 55 99 22. Howard and Shervais, 1973 72. Othberg, 2002 23. Hurlow, 2004 73. Othberg and Stanford, 1992 3 88 24. Janecke and others, 2001 74. Otto and others, 2005 18 53 25. Jenks and others, 1998 75. Phillips and others, 2009 58 10 94 14 44 26. Kauffman and others, 2009 76. Phillips and Welhan, 2011a 24 27. Kauffman and others, 2005 77. Phillips and Welhan, 2011b 54 70 66 28. Keeley and others, 2011 78. Phillips and Welhan, 2011c 8 29. Kiilsgaard and others, 1997 79. Phillips and Welhan, 2011d 54 91 30. Kiilsgaard and others, 2001 80. Phillips and Welhan, 2011e 16 15 97 31. Kiilsgaard and others, 2006 81. Phillips and Welhan, 2011f 90 32. Kuntz, 2003 82. Phillips and Welhan, 2011g 61 49 33. Kuntz and others, 2003 83. Pierce and others, 1983 31 34. Kuntz and others, 2007 84. USGS, 2006 (entire state) 11 9 50 35. Lewis and others, 1990 85. Riesterer and others, 2000 5 36. Lewis and others, 2002 86. Rodgers and others, 2006 29 32 80 75 89 37. Lewis and others, 2008 87. Rodgers and Othberg, 1999 30 92 38. Lewis and others, 2007a 88. Schmidt and others, 1994 73 33 79 39. Lewis and others, 2001 89. Scott, 1982 7 77 81 21 68 40. Lewis and others, 1999 90. Skipp, 1984 6 22 82 41. Lewis and others, 2007b 91. Skipp, 1985 62 76 78 2 34 42. Lewis and others, 2005 92. Skipp and Kuntz, 2009 60 20 71 43. Lewis and Derkey, 1999 93. Steely and others, 2005 98 72 44. Lewis and others, 2009 94. Stewart and others, 2010 1 51 59 45. Lewis and Stanford, 2002a 95. Vallier, 1998 87 46. Lewis and Stanford, 2002c 96. Waag and others, 1993 25 8685 47. Lewis and Stanford, 2002d 97. Wilson and Skipp, 1994 13 67 69 27 48. Lewis and Stanford, 2002b 98. Worl and others, 1991 28 57 52 49. Link and Janecke, 1999 99. Zientek and others, 2005 96 83 50. Link and others, 1995 12 17 89 23 93 63 74 Figure 1. Index map showing sources of geologic mapping. 2 3 Idaho Geological Survey Geologic Map 9 Idaho Geological Survey Geologic Map 9 Quaternary Qg glacial deposits Miocene Tcr Columbia River Basalt Group Northern Idaho Cambrian OCs Lakeview Limestone Gold Creek Quartzite and Rennie Shale Libby Formation Ymiu Bonner Formation Mt. Shields Formation Missoula Group Shepard Formation Ymil Snowslip Formation West-Central Idaho 2 km Ypi Wallace Formation Piegan Group Location of stratigraphic column Western facies of Helena Formation St. Regis Formation Revett Formation Yra Ravalli Group Tcr Columbia River Burke Formation Rock type Miocene 1 Basalt Group Location of stratigraphic column KJcw transition member limestone Cretaceous member h dolomitic Rock type JT_sv siltite KJcw member g Coon Hollow Formation 0 conglomerate quartzite Jurassic member f sandstone T_Pi siltite Hurwal Formation and red tuff of Pittsburg Landing calcareous siltstone T_Psd argillite J TR sv member e Yp gneiss and Martin Bridge Formation mudstone member d Mesoproterozoic schist Triassic volcanic rocks member c Doyle Creek Formation Prichard Formation orthogneiss Belt Supergroup and related rocks Tcr limestone mafic sill Wild Sheep Creek Formation members a intrusive rocks and b basalt flows TR Psd basalt flows gravel Hunsaker Creek Formation terrane Wallowa Seven Devils Group Windy Ridge Formation Permian 3 km Figure 3. Composite stratigraphic column for west-central Idaho. TR Pi Cougar Creek complex Modified from Vallier (1977; 1998). 2 Hauser Lake gneiss and related rocks 1 Ygs Metamorphosed 0 Prichard Formation Yagl Figure 2. Composite stratigraphic column for northern Idaho. Modified Laclede augen gneiss from Lewis and others (2002). Paleoproterozoic Gold Cup Quartzite XAm and Archean Pend Orielle gneiss ~ 2650 Ma basement 4 5 Idaho Geological Survey Geologic Map 9 Idaho Geological Survey Geologic Map 9 A. Lost River and Lemhi Ranges B. Southeastern Beaverhead Mountains (Hawley Creek Plate) (Cabin Plate) Eocene Tcv Challis Volcanic Group Tcv Challis Volcanic Group A. Wood River Valley B. Eastern Pioneer Mountains Dinwoody Formation Phosphoria Formation Phosphoria Formation TsR Permian and PIPs Snaky Canyon Snaky Canyon Formation PIPs PIPs Pennsylvanian 3 km Snaky Canyon Formation Challis Volcanic Group Formation Eocene Tcv Smiley Creek Conglomerate carbonate bank carbonate bank Iron Bog Creek Mississippian Ms 2 Ms Member t l McGowan Creek Formation u McGowan Creek Formation Permian a f 1 t Wood River Formation, s Brockie Lake u Three Forks Formation r Conglomerate Three Forks Formation h Ms PIPs Dollarhide Formation, and t Member Jefferson Formation Jefferson Formation r DSOs e Pennsylvanian Grand Prize Formation e Devonian to 0 n o Laketown Dolomite, i DSOs Argosy Creek Formation CZs Summerhouse Formation Group Sun Valley Ordovician Mississippian P Fish Haven Dolomite, Wilbert Formation Scorpion Mountain Copper Basin Group Kinnikinic Quartzite, and Member Devonian, Summerhouse Formation Lemhi Group Milligen Formation Drummond Mine Yl Silurian, and DSOs Limestone Neoproterozoic and CZs Wilbert Formation Ordovician Trail Creek Formation Little Copper Cambrian Phi Kappa Formation Formation Lawson Creek Formation XAm ~ 2450 Ma basement Tcv (only in northern Lost Wildhorse detachment fault Picabo and Jefferson formations River Range) DSOs Carey Dolomite Roberts Mountains Formation Copper Basin thrust fault Yls 3 km C. Pioneer Core Complex DSOs Swauger Formation Saturday Mountain Formation B Ordovician, Kinnikinic Quartzite OCi Cambrian, and OCs Ella Marble A 2 Neoproterozoic? Clayton Mine Quartzite Cash Creek Quartzite Hyndman shear zone Location of statigraphic columns 1 Mesoproterozoic Ym 695 Ma granite (Zi) B Ym Gunsight Formation A 0 ~2600 Ma orthogneiss C Rock type Wildhorse Mesoproterozoic Paleoproterozoic XAm and Archean dolomitic limestone gneiss complex Location of stratigraphic columns carbonate at Yellow Lake siltstone (Apple Creek Formation?) fossiliferous siltstone sandy limestone or siltite cherty Yl sandstone Rock type limestone or quartzite volcanic sandy limestone Lemhi Group rocks or granite dacite and andesite limestone or marble Big Creek Formation XWm dolomite gneiss conglomerate silty limestone Figure 5.