Andesite and basalt flows (NVTba;0)

Andesite and basalt flows

Generally poorly age constrained. This unit includes rocks originally mapped as the Pyramid sequence in Washoe County, the Mizpah Trachyte in Nye County, the Malpais Basalt, Rabbit Spring Formation, and Mira Basalt in Esmeralda County, and many other poorly dated unnamed basaltic and andesitic rocks around the State. It corresponds to unit Tba on the 1978 State map.

State	Nevada
Name	Andesite and basalt flows
Geologic age	Miocene and Oligocene
Lithologic constituents	Major Igneous > Volcanic > Mafic-volcanic > Andesite (Flow) Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)
References	Crafford, A.E.J., 2007, Geologic Map of Nevada: U.S. Geological Survey Data Series 249, 1 CD-ROM, 46 p., 1 plate; Scale 1:250,000. Extended unit descriptions taken from pamphlet that accompanies geologic data/map. https://pubs.er.usgs.gov/publication/ds249
NGMDB product	NGMDB product page for 81584
Counties	Churchill - Clark - Elko - Esmeralda - Eureka - Humboldt - Lander - Lincoln - Lyon - Mineral - Nye - Pershing - Storey - Washoe

Andesite and basalt flows

Crafford, A.E.J., 2007, Geologic Map of Nevada: U.S. Geological Survey Data Series 249, 1 CD-ROM, 46 p., 1 plate; Scale 1:250,000. Extended unit descriptions taken from pamphlet that accompanies geologic data/map.