Geologic units in Bingham county, Idaho

Additional scientific data in this geographic area

Basalt (Pleistocene and Pliocene). (Pleistocene and Pliocene) at surface, covers 48 % of this area

Flows and cinder cones of olivine tholeiite basalt in and near Snake River Plain. Largely Pleistocene (<2.6 Ma) but includes flows as old as 3 Ma. Covered with 1-3 m (3-10 ft) of loess. (Quaternary to Eocene Continental Volcanic and Intrusive Rocks).

Alluvial deposits. (Quaternary) at surface, covers 9 % of this area

Deposits in valleys consisting of gravel, sand, and silt. Includes younger terrace deposits. May contain some glacial deposits and colluvium in uplands. (Quaternary Sediments).

Basalt (Quaternary). (Quaternary) at surface, covers 7 % of this area

Flows and cinder cones of olivine tholeiite basalt and minor latite and alkaline basalt less than 15 ka; includes Shoshone, Craters of the Moon, Wapi, Cerro Grande, and Hells Half Acre lava fields. Little or no loess cover. (Quaternary to Eocene Continental Volcanic and Intrusive Rocks).

Fluvial and lake sediment. (Quaternary) at surface, covers 6 % of this area

Largely fine-grained sediment, in part playa deposits of evaporative lakes; includes Snake River Group and Bruneau Formation in central Snake River Plain and glacial lake deposits in Bonners Ferry area of northern Idaho. Also includes travertine and tufa northeast of Bancroft and Lake Thatcher sediments in the Gem Valley south of Grace. (Quaternary Sediments).

Sedimentary rocks associated with Basin and Range extension. (Quaternary, Pliocene, and Miocene) at surface, covers 5 % of this area

Fluvial, fan, and lacustrine deposits and intercalated volcanic rocks of the Basin and Range Province (~16-2 Ma); consolidated to weakly consolidated sandstone, siltstone, arkose, conglomerate, mudstone, tuffaceous sediment, basalt, basaltic tephra, and rhyolite tuff. Includes deposits of Lake Idaho (Idaho Group) in western Snake River Plain and Salt Lake Formation deposited in Basin and Range Province of east-central Idaho. (Quaternary to Eocene Continental Sediments and Sedimentary Rocks).

Sedimentary rocks (Triassic). (Triassic) at surface, covers 5 % of this area

Red mudrock and fine-grained sandstone and marine limestone; includes Dinwoody, Woodside, Thaynes, and Ankareh formations in eastern Idaho thrust belt. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Windblown sand deposits. (Quaternary) at surface, covers 4 % of this area

Fine- and medium-grained sand dunes in southern Idaho; includes Bruneau and St. Anthony dune fields. (Quaternary Sediments).

Rhyolite (Pliocene and Miocene). (Pliocene and Miocene) at surface, covers 3 % of this area

Rhyolite tuffs and flows of Heise volcanic field (6.6-4.5 Ma; includes Blacktail Creek, Walcott, Conant Creek, and Kilgore tuffs), and rhyolite domes and flows of Magic Reservoir area (6.6-3 Ma). (Quaternary to Eocene Continental Volcanic and Intrusive Rocks).

Sedimentary rocks (Cretaceous). (Cretaceous) at surface, covers 3 % of this area

Marine and deltaic sandstone and shale of Cordilleran foreland basin (includes Gannett Group, Frontier, Mowry, Kootenay, and Thermopolis formations) in eastern Idaho thrust belt. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Loess deposits. (Pleistocene) at surface, covers 3 % of this area

Wind-deposited quartzose and calcareous silt in southeastern Idaho. Only shown where thick enough to mask older units; commonly 7-15 m (23-50 ft) thick. (Quaternary Sediments).

Sedimentary rocks (Permian and Pennsylvanian). (Permian and Pennsylvanian) at surface, covers 2 % of this area

Marine phosphorite, shale, and chert of Phosphoria Formation, fine-grained sandstone and mudrock of Wells, Quadrant, Amsden, and Shedhorn formations, and fine-grained sandstone, carbonaceous mudstone, and limestone of the Snaky Canyon Formation and Sun Valley and Oquirrh groups. Located in south-central and eastern Idaho. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Sedimentary rocks (Jurassic). (Jurassic) at surface, covers 1 % of this area

Marginal marine and marine sandstone and limestone; includes Nugget, Twin Creek, Preuss, Morrison, and Stump formations in eastern Idaho thrust belt. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Sedimentary rocks (Mississippian). (Mississippian) at surface, covers 1 % of this area

Marine limestone of Mississippian carbonate banks and turbiditic sandstone, mudstone, and conglomerate of Antler flysch trough; includes Madison and Lodgepole formations and Chesterfield Range Group of southeastern Idaho; McGowan Creek Formation, White Knob Limestone, and overlying carbonate bank of Lost River Range; and Copper Basin Group of Pioneer Mountains. Includes poorly dated Salmon River assemblage east of Stanley, consisting of argillite, siltstone, calcareous sandstone, and limestone. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Challis Volcanic Group. (Eocene) at surface, covers 0.8 % of this area

Dacite, andesite, and rhyolite tuffs and flows and subordinate basalt and latite flows; covers large area in south-central Idaho. Includes Absaroka Volcanic Group near Henrys Lake and scattered volcanic rocks in eastern and northern Idaho. (Eocene Challis Magmatic Complex and Related Sedimentary Rocks).

Sediments and sedimentary rocks (Pleistocene and Pliocene). (Pleistocene and Pliocene) at surface, covers 0.6 % of this area

Older gravel, sand, and silt deposited in fans, streams, and lakes. Includes older terrace gravels and Tuana Gravel northwest of Twin Falls. (Quaternary to Eocene Continental Sediments and Sedimentary Rocks).

Lake Bonneville deposits. (Pleistocene) at surface, covers 0.3 % of this area

Silt, clay, sand, and gravel deposited in and at margins of former Lake Bonneville (33-11 calibrated ka) and sand and gravel deposited in giant flood bars by outburst floods from the lake (17.4 calibrated ka). The 1,575-m (5,170 ft) Lake Bonneville shoreline was used to determine the maximum extent of the lake deposits. Flood deposits follow Bonneville flood path from near Downey and the Portneuf River westward along the Snake River to Lewiston. They include sand and silt deposited in slack-water areas to 740 m (2,430 ft) elevation in the Boise, Weiser, Payette, and Snake river drainages. (Quaternary Sediments).

Alluvial-fan deposits. (Quaternary) at surface, covers 0.3 % of this area

Gravel and subordinate sand and silt deposited at mouths of canyons; largest fans are in Basin and Range Province in east-central and southeastern Idaho. (Quaternary Sediments).

Rhyolite (Pleistocene). (Pleistocene) at surface, covers 0.2 % of this area

Rhyolite tuffs, flows, and domes; includes Yellowstone Group (2.0-0.6 Ma) and isolated domes on Snake River Plain and north of Soda Springs (less than 2.0 Ma). (Quaternary to Eocene Continental Volcanic and Intrusive Rocks).

Sedimentary rocks (Devonian to Ordovician). (Devonian to Ordovician) at surface, covers 0.2 % of this area

Marine dolostone and limestone and sandstone in east-central and southeastern Idaho (Summerhouse, Kinnikinic, and Swan Peak sandstones, Fish Haven, Laketown, Jefferson, Three Forks, and Darby formations) and deep-water carbonaceous mudrocks of Phi Kappa, Trail Creek, and Milligen formations east of Ketchum. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).

Sedimentary rocks (Ordovician and Cambrian). (Ordovician and Cambrian) at surface, covers 0.2 % of this area

Marine limestone, dolomite, and subordinate shale and sandstone of Cambrian carbonate bank of southeast Idaho stratigraphically up to St. Charles Formation and Ordovician Garden City Limestone. Includes Bayhorse succession (Cash Creek Quartzite, Garden Creek Phyllite, Bayhorse Dolomite, Ramshorn Slate, and Clayton Mine Quartzite) of Clayton area and Pioneer Mountains; quartzite of Kamiak Butte north of Moscow; and Cambrian Gold Creek quartzite, Rennie Shale, and Lakeview Limestone east of Bayview. (Paleocene to Neoproterozoic Sedimentary and Igneous Rocks of the Cordilleran System).