Sedimentary rocks (Eocene).

Fluvial, lacustrine, and air-fall deposits of conglomerate, volcanic sandstone, mudstone, and tuff near Challis, conglomerate north of Sandpoint, and conglomerate and sandstone of the Wasatch Formation in extreme southeastern Idaho. (Eocene Challis Magmatic Complex and Related Sedimentary Rocks).
State Idaho
Name Sedimentary rocks (Eocene).
Geologic age Eocene
Lithologic constituents
Major
Sedimentary > Clastic > Conglomerate (Bed, Tuffaceous)
Sedimentary > Clastic > Mudstone (Bed, Tuffaceous)
Sedimentary > Clastic > Sandstone (Bed, Tuffaceous)Volcanic sandstone.
References

Lewis, Reed S., Link, Paul K., Stanford, Loudon R., and Long, Sean P., Geologic Map of Idaho, 2012, Idaho Geological Survey, Geologic Map 9 (M-9); Scale 1:500,000.

NGMDB product
Counties Bear Lake - Bonner - Custer - Lemhi