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Mineral Resources > Online Spatial Data > Geology > by state > Idaho Geology

Geologic units in Bear Lake county, Idaho

[Additional scientific data in this geographic area]

Siltstone, shale, and limestone; Early Triassic marine to non-marine epicontinental deposits; southeastern Idaho (Early Triassic) at surface, covers 6 % of this area

Lower Triassic shallow-marine to non-marine sediments; limestone and chert above shaley sandstone, siltstone, and limestone of eastern Idaho.

Lithology: siltstone; shale; limetstone; chert; dolostone (dolomite)

Gravel, sand, and silt; Quaternary; alluvium (Quaternary) at surface, covers 20 % of this area

Quaternary alluvium; may contain some glacial deposits and colluvium in uplands

Lithology: alluvium; alluvial terrace; floodplain; alluvial fan; colluvium

Dolostone, shale, and chert; Silurian marine inner continental-shelf deposits (Late and Middle Silurian) at surface, covers 1 % of this area

Upper and Middle Silurian fossiliferous dolomite; clay, silt and sand near base.

Lithology: dolostone (dolomite); shale; chert

Chert, shale, phosphorite, and carbonates; Permian restricted marine epicontinental-basin deposits; southeastern Idaho (Permian) at surface, covers 0.3 % of this area

Permian phosphatic sandstone, mudstone and chert of east-central Idaho.

Lithology: chert; shale; phosphorite; dolostone (dolomite); arenite; limestone

Arenite, carbonate, conglomerate, and shale; Late Proterozoic rifted continental margin; southeastern Idaho (Late Proterozoic) at surface, covers 7 % of this area

Uppermost Younger Precambrian massive quartzite with carbonate beds of central and southeastern Idaho; overlies (Z1s).

Lithology: arenite; carbonate; conglomerate; shale

Quaternary alluvium and colluvium (Quaternary) at surface, covers < 0.1 % of this area

Lithology: alluvium; colluvium

Triassic and Jurassic sedimentary rocks in Salt Lake City-Coalville-Randolph region (Early Jurassic) at surface, covers < 0.1 % of this area

Lithology: sandstone

Salt Lake Formation (Phanerozoic | Cenozoic | Tertiary | Miocene Pliocene) at surface, covers < 0.1 % of this area

SALT LAKE FORMATION--White, gray, and green limy tuff, siltstone, sandstone, and conglomerate.

Lithology: fine-grained mixed clastic; medium-grained mixed clastic; mixed clastic/carbonate; mixed clastic/volcanic

Siltstone, evaporites, and redbeds; Late Jurassic Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Late Jurassic) at surface, covers 13 % of this area

Upper Jurassic shallow-marine to non-marine sediments; glauconitic and variegated sandstone, siltstone and oolitic limestone of eastern Idaho.

Lithology: siltstone; shale; sandstone; limestone; evaporite

Alluvium and Colluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers < 0.1 % of this area

ALLUVIUM AND COLLUVIUM--Clay, silt, sand, and gravel in flood plains, fans, terraces, and slopes.

Lithology: alluvium; colluvium

Clastic debris; Quaternary colluvium, fanglomerate, talus, and glacial deposits; upland-valley margins (Quaternary) at surface, covers 2 % of this area

Quaternary colluvium, fanglomerate, and talus plus some glacial debris in upland valleys.

Lithology: alluvium; glacial drift; colluvium

Coralline Limestone, sandstone, siltstone, shale, chert, and phosphorite; Mississippianshallow marine inner continental-shelf deposits; east-central Idaho, central Idaho (Mississippian ) at surface, covers 2 % of this area

Mississippian shallow-water coralline limestone interval of southern Idaho.

Lithology: limestone; sandstone; siltstone; shale; chert; phosphorite

Stump Formation, Preuss Sandstone or Redbeds, and Twin Creek Limestone (Phanerozoic | Mesozoic | Jurassic-Middle Jurassic-Late) at surface, covers < 0.1 % of this area

STUMP FORMATION, PREUSS SANDSTONE or REDBEDS, and TWIN CREEK LIMESTONE. STUMP FORMATION--Glauconitic siltstone, sandstone, and limestone. PREUSS SANDSTONE OR REDBEDS--Purple, maroon, and reddish-gray sandy siltstone and claystone; contains salt and gypsum in thick beds in some subsurface sections. TWIN CREEK LIMESTONE--Greenish-gray shaly limestone and limy siltstone. Includes Gypsum Spring Member.

Lithology: fine-grained mixed clastic; limestone; sandstone; evaporite

Wasatch Formation (TB) (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

WASATCH FORMATION Diamictite and sandstone--Diamictite grades laterally into other members of the formation.

Lithology: clastic; medium-grained mixed clastic; fine-grained mixed clastic

Tuffaceous shale, sandstone, conglomerate, and lignite; Eocene to Pliocene alluvial and lacustrine deposits; central and southern Idaho (Tertiary) at surface, covers 7 % of this area

Tertiary continental sediments; predominantly Upper Tertiary in age; subdivisions are:(Tpd, Tmd, and Ted).

Lithology: shale; sandstone; conglomerate; tuff; siltstone; lignite; bentonite; claystone; limestone

Siltstone, shale, sandstone, and limestone; Jurassic Cordilleran retroarc-foreland-basin deposits (subunits are Jl and Ju); southeastern Idaho (Jurassic) at surface, covers 0.1 % of this area

Jurassic shallow-marine to non-marine sediments of eastern Idaho; subdivisions are (Jl and Ju).

Lithology: siltstone; shale; sandstone; limestone

Limestone, arenite, shale, dolostone, and siltstone; Upper Proterozoic to Cambrian marine continental-shelf deposits; southeastern Idaho (Cambrian) at surface, covers 6 % of this area

Cambrian marine dolomite, limestone, claystone, and quartzite; grades into Precambrian.

Lithology: limestone; arenite; shale; dolostone (dolomite); siltstone

Tertiary (1) sedimentary rocks in Logan-Huntsville Allochthon (Late Cretaceous to Early Eocene) at surface, covers < 0.1 % of this area

Lithology: conglomerate; medium-grained mixed clastic

Glacial debris; Late Pleistocene till, outwash, and alluvium of valley glaciers; high mountain valleys (Late Pleistocene ) at surface, covers 0.7 % of this area

Pleistocene upland valley deposits; commonly derived from alpine glaciation.

Lithology: till; outwash; alluvium

Jurassic (1) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Middle to Late Jurassic) at surface, covers < 0.1 % of this area

Lithology: limestone; sandstone; fine-grained mixed clastic; evaporite

Dolostone, limestone, arenite, chert, and conglomerate; Ordovician marine continental-shelf deposits; southeastern Idaho (Ordovician) at surface, covers 9 % of this area

Ordovician marine dolomite, quartzite, and limestone; subdivisions are (Ou and Ol).

Lithology: dolostone (dolomite); limestone; arenite; chert; conglomerate

Open Water (Holocene) at surface, covers 6 % of this area

Lakes and streams

Lithology: water

Limestone and sandstone; Early Jurassic Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Early Jurassic) at surface, covers 4 % of this area

Lower Jurassic shallow-marine to non-marine sediments; shaley, sandy limestone overlaying red, crossbedded sandstone of eastern Idaho.

Lithology: limestone; sandstone

Sandstone, conglomerate, siltstone, tuff, claystone, limestone, and diatomite; Pliocene tuffaceous alluvial and lacustrine deposits; Snake River Plain and vicinity, southeastern Idaho (Pliocene ) at surface, covers 11 % of this area

Pliocene stream and lake deposits; may be due to volcanic and block-faulting events.

Lithology: sandstone; conglomerate; siltstone; tuff; claystone; shale; limestone

Limestone, sandstone, dolostone, and chert; Permian to Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho; (Early Permian to Early Pennsylvanian) at surface, covers 3 % of this area

Lower Permian to Lower Pennsylvanian chert, limestone, and sandstone of southern Idaho; subdivisions are (Ps, and PNs).

Lithology: limestone; sandstone; dolostone (dolomite); chert; siltstone; shale

Sandstone, siltstone, shale, limestone, and coal ; Early Cretaceous Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Early Cretaceous) at surface, covers 0.9 % of this area

Lower Cretaceous shale, siltstone, red-bed sandstone and fresh-water limestone.

Lithology: sandstone; siltstone; shale; limestone; coal

Dolostone, limestone, sandstone, shale, and conglomerate; Devonian marine continental-shelf deposits; east-central and southeastern Idaho (Devonian) at surface, covers 0.6 % of this area

Devonian bedded dolomite and limestone interval of eastern and southern Idaho.

Lithology: dolostone (dolomite); limestone; sandstone; shale; conglomerate

Sandstone, limestone, and shale; Upper Triassic marine to non-marine epicontinental deposits; southeastern Idaho (Late Triassic) at surface, covers 1 % of this area

Upper Triassic shallow-marine to non-marine sediments; oxidized shale, siltstone, limestone, and conglomeratic sandstone of eastern Idaho.

Lithology: shale; siltstone; limestone; sandstone; chert