Scientific data near [39.29000,-120.59000]

Search area extends approximately 2.2 km east-west and 2.9 km north-south.

Geographic context

Counties, states, countries, continents, or oceans
Placer	county
California	state
United States	country
North America	continent
Land	continent
Map quadrangles, from USGS or Canadian NTS
Cisco Grove	quadrangle 1:24,000 scale
Truckee	quadrangle 1:100,000 scale
Chico	quadrangle 1:250,000 scale
Watershed boundaries (USGS hydrologic units)
North Fork American	hydrologic unit
Lower Sacramento	hydrologic accounting unit
Sacramento	hydrologic subregion
California	hydrologic region
Areas administered by US Federal agencies
Tahoe National Forest	National Forest
National Forest FS	Type of land area
FS	Federal land areas administered by FS

Geology of US states

Digital geologic maps of the US states with consistent lithology, age, GIS database structure, and format

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Unit	State	Lithology
Mesozoic gabbroic rocks, unit 2 (undivided)	CA	Triassic to Cretaceous
Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges)	CA	Permian to Tertiary; most Mesozoic
Paleozoic marine rocks, undivided, unit 4 (Western Sierra Nevada)	CA	Ordovician to Triassic
Tertiary pyroclastic and volcanic mudflow deposits, unit 9 (Cascade Range)	CA	Tertiary (2-24 Ma)
Ultramafic rocks, chiefly Mesozoic, unit 2 (Western Sierra Nevada and Klamath Mountains)	CA	Late Proterozoic(?) to Early Jurassic

Airborne geophysical surveys

Aerial surveys of magnetic anomaly and gamma ray emission; older surveys were analog record which have been digitized, newer surveys collected data in digital form.

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ID	Data type	Description
North Fork American	M-D	North Fork American 860 line km with spacing 1.10 km over parts of CA
Chico	M/R-D	Chico 4869 line km with spacing 4.80 km over parts of CA-NV

Estimates of undiscovered mineral resources

National Mineral Resource Assessment 1998: Estimates of the number of undiscovered mineral resources of gold, silver, copper, lead, and zinc within identified permissive tracts (geographic areas in which mineral deposits may form).

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Tract	Deposit Type	Mineralization age
PC03	Skarn Cu	Mesozoic
PC08	Porphyry Cu	Mesozoic
PC40	Low-sulfide Au-quartz vein	Mesozoic

The continental crust

Seventy-seven major components of the North American continent were delineated at a general scale (1:5,000,000); including the general composition, geological environment, and types of primary metals endowments that can be expected in each domain.

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Domain	Crust type	Region
Shoofly-Olds Ferry	Oceanic arc	Western Cordillera

Asbestos mines, prospects, and occurrences in the US

Location and mineralogical characteristics of former mines, prospects, and occurrences of asbestos in the continental US. No asbestos producing mines are currently active. Data here are drawn from several previously published reports.

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Deposit name	Deposit type	Location
Monumental Hill	occurrence	Placer, CA

Global assessment of undiscovered copper resources

Deposits, prospects, and permissive tracts for porphyry and sediment-hosted copper resources worldwide, with estimates of undiscovered copper resources.

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Tract name	Deposit type	Geology
Cascade Arc	porphyry copper	U.S. part of a continental margin arc that formed during subduction of the Pacific and Juan de Fuca plates beneath western North America
Sierran Arc	porphyry copper	A composite island-continental margin arc that formed during subduction of the Farallon Plate beneath western North America
Western U.S. and Sonoran Desert Jurassic Arc	porphyry copper	U.S. and Mexican parts of a composite island-continental margin arc that formed during subduction of the Farallon Plate beneath western North America