Province Name


Incorporated map units/structures

Rock Type




Age of Deformation

Snake River Plain
NE-SW belt across southern Idaho
Idavada Volcanics, Yellowstone Volcanics, Basalt, Snake River Basalt, and some Quaternary Sedimentary rocks
Volcanic: rhyolite and basalt
17 Ma-Present
Miocene to Holocene
Subsidence, dike intrusion
Up to Holocene
Columbia Plateau
Western edge of Idaho
Columbia River Basalt
Volcanic: rhyolite and basalt
Mainly 16 to 17 Ma, a few later flows
Middle Miocene
Uplift and folding
Late Miocene to Holocene
Idaho-Wyoming Thrust Belt
SE Idaho, cut by Snake River Plain
NW-SE trending thrust faults which cut through mostly Paleozoic & Mesozoic sedimentary rocks
Sedimentary: sandstone, shale, limestone
700-150 Ma
Neoproterozoic, Paleozoic, Triassic, Jurassic
Thrusting and Folding in Cordilleran Orogenic Belt
Late Cretaceous
Northern Thrust Belt
NE Idaho
NW-SE trending thrust faults, which cut through Precambrian Sedimentary rocks
Sedimentary: sandstone, shale, limestone (Belt Supergroup)
1450-1400 Ma
Thrusting and Folding
Late Cretaceous
Basin and Range
SE Idaho, cut by Snake River Plain
NW-SE trending faults (normal faults, extensional forces)
Sedimentary: sandstone, shale, limestone
700-150 Ma
Mostly Neoproterozoic and Paleozoic
Linear Mountain Ranges, broken by normal faults
10 Ma-Holocene (present)
Idaho Batholith
Central & Northern Idaho
Idaho Batholith, Diorite
Intrusive igneous: granodiorite and tonalite
110-60 Ma
Late Cretaceous
Paleocene Uplift & Erosion & Basin and Range Extension
Paleocene (~60-50 Ma) and 10 Ma to present
Challis Volcanics
Central Idaho
Challis Volcanics
Extrusive Igneous: andesite and dacite, also intrusive pink granite
52-45 Ma
Paleogene basin formation and Neogene Basin and Range Extension
40 Ma-Holocene (present)
Accreted Terranes
Eastern edge Central Idaho
Seven Devils Group
Exotic Terranes: Paleozoic limestone on top of oceanic volcanic rock, also Jurassic intrusions
~370-250 Ma, intrusions 150 to 170 Ma intrusions
Paleozoic and Mesozoic
Middle Cretaceous accretion of terranes onto western Idaho and Basin and Range Extension
Mid-Cretaceous (120-100 Ma) and 10 Ma to present