Siltstone, shale, conglomerate, and limestone

Includes detrital deposits of continental origin, and locally derived fluvial and lacustrine clastic rocks, some interbedded with siltstone and freshwater limestone. Outcrops are concentrated in three separate areas of the State. In each place, limited biostratigraphic data indicate these rocks are Cretaceous. The King Lear Formation in the Jackson Mountains in Humboldt County lies unconformably on Triassic and older rocks of the Black Rock-Jackson terrane. The Newark Canyon Formation crops out mostly in Eureka and White Pine Counties but extends into Elko and Nye Counties as well, and rests unconformably on Ordovician to Permian rocks. In places it is difficult to distinguish Upper Devonian, Pennsylvanian, and Permian clastic rocks also derived from the nearby underlying bedrock from the Newark Canyon Formation, and some confusion still exists. The Willow Tank Formation in Clark County lies unconformably on Jurassic rocks and is overlain by what was mapped as the Baseline Sandstone and Overton Fanglomerate (now referred to as the Overton Conglomerate Member of the Baseline Sandstone), all of Cretaceous age.
State Nevada
Name Siltstone, shale, conglomerate, and limestone
Geologic age Cretaceous
Lithologic constituents
Sedimentary > Clastic > Siltstone (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
Sedimentary > Clastic > Mudstone > Shale (Bed)
Sedimentary > Carbonate > Limestone (Bed)
NGMDB product
Counties Clark - Elko - Eureka - Humboldt - Nye - White Pine