This assemblage is composed of Upper Triassic basinal-marine volcanic and carbonate rocks overlain by Lower Jurassic fine-grained, marine siliciclastic and tuffaceous sedimentary rocks, and by partly nonmarine sandstone, coarse clastic rocks, and volcanic rocks of late Early Jurassic and possibly younger age. This assemblage has stratigraphic similarities to the Luning-Berlin and Pamlico-Lodi assemblages, but shares only part of their late Mesozoic structural history, and is separated from them by the linear trace of the northwesterly trending Pine Nut fault (Oldow, 1984a; Silberling, Jones, and others, 1992). Structurally, the rocks are involved in only a single phase of tight to isoclinal folds with north-northwest striking axial planes, and no major internal thrust faults are known (Oldow, 1984a). The Pine Nut assemblage crops out in southern Washoe, Lyon, Douglas, Carson, and Mineral Counties, and includes rocks originally mapped as the Excelsior Formation, the Peavine sequence, and other metasedimentary and metavolcanic rocks.