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Geologic units in Storey county, Nevada

Additional scientific data in this geographic area

Tuffaceous sedimentary rocks (Late Eocene to Late Miocene) at surface, covers 19 % of this area

TUFFACEOUS SEDIMENTARY ROCKS-Locally includes minor amounts of tuff

Intrusive rocks of mafic and intermediate composition (Miocene to Quaternary) at surface, covers 15 % of this area

INTRUSIVE ROCKS OF MAFIC AND INTERMEDIATE COMPOSITION

Alluvial deposits (Quaternary) at surface, covers 15 % of this area

ALLUVIAL DEPOSITS-Locally includes beach and sand dune deposits

Basalt flows (Miocene to Quaternary) at surface, covers 12 % of this area

BASALT FLOWS-Locally includes maar deposits

Basalt flows (Late Miocene to Middle Miocene) at surface, covers 10 % of this area

BASALT FLOWS

Lithology: basalt

Andesite and related rocks of intermediate composition (Late Miocene to Middle Miocene) at surface, covers 7 % of this area

ANDESITE AND RELATED ROCKS OF INTERMEDIATE COMPOSITION-Flows and breccias

Intrusive rocks of mafic to intermediate composition (Eocene to Miocene) at surface, covers 5 % of this area

INTRUSIVE ROCKS OF MAFIC TO INTERMEDIATE COMPOSITION

Shale, sandstone, volcanogenic clastic rocks, andesite, rhyolite, and locally thick carbonate units (Late Triassic to Early Cretaceous) at surface, covers 4 % of this area

SHALE, SANDSTONE, VOLCANOGENIC CLASTIC ROCKS, ANDESITE, RHYOLITE, AND LOCALLY THICK CARBONATE UNITS-Undivided sequence locally containing recognizable equivalents of the Luning and Dunlap Formations

Andesite and basalt flows (Early Miocene to Early Pliocene) at surface, covers 4 % of this area

ANDESITE AND BASALT FLOWS-Mostly in about 17 to about 6 m.y. age range. In Humboldt County, locally includes rocks as old as 21 m.y. May include rocks younger than 6 m.y. in places

Lithology: basalt; andesite; shoshonite

Older alluvial deposits (Miocene to Quaternary) at surface, covers 3 % of this area

OLDER ALLUVIAL DEPOSITS

Granitic rocks (Cretaceous) at surface, covers 2 % of this area

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Rhyolitic intrusive rocks (Eocene to Miocene) at surface, covers 0.9 % of this area

RHYOLITIC INTRUSIVE ROCKS

Lithology: granitoid

Welded and nonwelded silicic ash-flow tuffs (Early Oligocene to Early Miocene) at surface, covers 0.7 % of this area

WELDED AND NONWELDED SILICIC ASH-FLOW TUFFS-Locally includes thin units of air-fall tuff and sedimentary rock

Lithology: rhyolite; dacite; trachyte

Rhyolitic flows and shallow intrusive rocks (Miocene to Quaternary) at surface, covers 0.4 % of this area

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Granitic rocks (Paleocene to Late Miocene) at surface, covers 0.4 % of this area

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite