Coon Hollow and Weatherby formations.

Marine mudstone and subordinate conglomerate and sandstone of the Coon Hollow Formation south of Lewiston and turbiditic sandstone, mudstone, volcanic conglomerate, and andesite and rhyolite tuff of the Weatherby Formation north of Weiser. (Mesozoic-Paleozoic Rocks of the Blue Mountains Island-Arc Complex).
State Idaho
Name Coon Hollow and Weatherby formations.
Geologic age Cretaceous and Jurassic
Lithologic constituents
Major
Sedimentary > Clastic > Mudstone (Bed)
Minor
Sedimentary > Clastic > Sandstone
Sedimentary > Clastic > Conglomerate (Bed)
Incidental
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic-tuff)Andesite and rhyolite tuff of the Weatherby Formation north of Weiser.
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic-tuff)Andesite and rhyolite tuff of the Weatherby Formation north of Weiser.
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 Adams - Idaho - Lewis - Nez Perce - Washington