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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: 2523

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

Remagnetization of the Coast Range Ophiolite and Lower Part of the Great Valley Sequence in Northern California and Southwest Oregon Remagnetization of the Coast Range Ophiolite and Lower Part of the Great Valley Sequence in Northern California and Southwest Oregon

Overprinted magnetizations have been found at four localities in the Middle Jurassic Coast Range ophiolite and the overlying Upper Jurassic and Lower Cretaceous Great Valley sequence in northern California and at one locality in the partially correlative Lower Cretaceous Days Creek Formation in southwest Oregon. At Del Puerto Canyon, on the east side of the Diablo Range, a pilot study of...
Authors
L.S. Frei, M. Clark Blake

Attenuation of the Coast Range ophiolite by extensional faulting and nature of the Coast Range "thrust," California Attenuation of the Coast Range ophiolite by extensional faulting and nature of the Coast Range "thrust," California

The late Mesozoic Coast Range ophiolite and Great Valley sequence in California were juxtaposed against the Franciscan Complex during a long tectonic history that included imbricate thrust faulting, low‐angle detachment, and high‐angle reverse faulting. Many low‐angle faults previously mapped as thrusts invariably juxtapose younger over older rocks, suggesting a normal sense of offset...
Authors
A. S. Jayko, M. Clark Blake, Tekla Harms

In search of the Abrams post office, Trinity County In search of the Abrams post office, Trinity County

An understanding of earth history depends in part on stratigraphy, a division of geology in which the distinctive features of natural units or formations of layered rocks are studied and described and names are assigned to them. The procedures for describing and naming rock units in a uniform way are incorporated in documents known as stratigraphic codes. The North American Stratigraphic...
Authors
Marvin A. Lanphere, William P. Irwin
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