Ultramafic rocks and serpentine

Ultramafic rocks are present in very small belts or lenses in a few places across the State. In the Candelaria Hills along the Mineral-Esmeralda County boundary, they crop out in a thrust complex that overlies the Candelaria Formation (TRcl). At Willow Spring, at the southern end of the Toquima Range south of Manhattan, serpentine is exposed again adjacent to the Candelaria Formation and deformed lower Paleozoic rocks (OCtd). A few small outcrops also are present on the east side of the Toquima Range near Belmont adjacent to lower Paleozoic rocks. In the Toiyabe Range in Nye County, scattered outcrops of serpentine form a narrow north-south trending belt adjacent to the Golconda terrane (GC), deformed lower Paleozoic rocks (OCtd, Ctd), and the Siliciclastic overlap assemblage. An early Triassic conodont was recovered near the serpentine near Marysville Canyon (Poole and Wardlaw, 1978), although the Candelaria Formation does not show on the map in this area. All of these exposures of ultramafic rocks are in a similar relative tectonic position above deformed lower Paleozoic rocks and the Siliciclastic overlap assemblage, and below the structurally overlying Golconda terrane. A narrow belt of serpentine and gabbro is exposed at the northern edge of the Golconda terrane in the Hot Springs Range in Humboldt County. In this case, the ultramafic rock is structurally above the Golconda terrane, and beneath the overlying Mesozoic Jungo terrane (JO).
State Nevada
Name Ultramafic rocks and serpentine
Geologic age Triassic or upper Paleozoic
Lithologic constituents
Metamorphic > Metaigneous > Serpentinite
Igneous > Plutonic > Ultramafic
NGMDB product
Counties Esmeralda - Humboldt - Mineral - Nye