Skip to main content
U.S. flag

An official website of the United States government

Publications

Results from our Program’s research and minerals information activities are published in USGS publications series as well as in outside journals.  To follow Minerals Information Periodicals, subscribe to the Mineral Periodicals RSS feed.

Filter Total Items: 2505

Models of grades and tonnages of some lode tin deposits Models of grades and tonnages of some lode tin deposits

Descriptive and grade/tonnage models have recently been built for many types of deposits. Such models consist of descriptions of mineralogy, host rocks, ore textures, controls, alteration, geochemical signatures, age, and tectonic settings, together with statistical models of grades, tonnages, and contained metal of deposits of each type. The models are used to identify areas that may...
Authors
W. D. Menzie, B.L. Reed, Donald A. Singer

Geologic map of the Ajo and Lukeville 1° by 2° quadrangle, southwest Arizona Geologic map of the Ajo and Lukeville 1° by 2° quadrangle, southwest Arizona

No abstract available.
Authors
Floyd Gray, R. J. Miller, M. J. Grubensky, R. M. Tosdal, G. B. Haxel, D. W. Peterson, D. J. May, L. T. Silver

The relative contribution of accretion, shear, and extension to Cenozoic tectonic rotation in the Pacific Northwest The relative contribution of accretion, shear, and extension to Cenozoic tectonic rotation in the Pacific Northwest

Large Cenozoic clockwise rotations defined by paleomagnetic data are an established fact in the Pacific Northwest, and many tectonic models have been proposed to explain them, including (1) rotation of accreted oceanic microplates during docking, (2) dextral shear between North America and northward-moving oceanic plates to the west, and (3) microplate rotation in front of an expanding...
Authors
Ray E. Wells, Paul L. Heller

Paleomagnetic results from the Shasta Bally Plutonic Belt in the Klamath Mountains Province, northern California Paleomagnetic results from the Shasta Bally Plutonic Belt in the Klamath Mountains Province, northern California

Available paleomagnetic data show approximately 100° of clockwise rotation for Permian and Triassic strata of the Eastern Klamath terrane. Jurassic strata of this terrane are rotated approximately 60° clockwise, which is comparable to rotations reported for Jurassic plutons that occur elsewhere in the Klamath Mountains province. Paleomagnetic data obtained during the present study from...
Authors
Edward A. Mankinen, William P. Irwin, C. Sherman Gromme

Element concentrations in soils and other surficial materials of Alaska Element concentrations in soils and other surficial materials of Alaska

Mean concentrations of 35 elements, ash yields, and pH have been estimated for samples of sils and other unconsolidated surficial materials from 266 collection locations throughout Alaska. These background values can be applied to studies of environmental geochemistry and health, wildlife management, and soil-forming processes in cold climates and to computation of element abundances on...
Authors
L. P. Gough, R. C. Severson, H.T. Shacklette

Crustal extension along a rooted system of imbricate low-angle faults: Colorado River extensional corridor, California and Arizona Crustal extension along a rooted system of imbricate low-angle faults: Colorado River extensional corridor, California and Arizona

The upper 10 to 15 km of crystalline crust in the 100-km-wide Colorado River extensional corridor of mid-Tertiary age underwent extension along an imbricate system of gently dipping normal faults. Detachment faults cut gently down-section eastward in the direction of tectonic transport from a headwall breakaway, best expressed in the Old Woman Mountains, California. Successively higher...
Authors
Keith A. Howard, B.E. John

Thermal maturity of tectonostratigraphic terranes within the Franciscan Complex, California Thermal maturity of tectonostratigraphic terranes within the Franciscan Complex, California

Indicators of organic metamorphism provide valuable tools for analyzing the thermal history of tectonostratigraphic terranes. Paleotemperature estimates derived from vitrinite reflectance, for example, are more precise than values based upon inorganic mineral assemblages in low‐grade rocks. Isothermal geometries must be interpreted within the context of structural and stratigraphic data...
Authors
M.B. Underwood, M. Clark Blake, D. G. Howell
Was this page helpful?