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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.

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Porphyry copper deposit density Porphyry copper deposit density

Estimating numbers of undiscovered mineral deposits has been a source of unease among economic geologists yet is a fundamental task in considering future supplies of resources. Estimates can be based on frequencies of deposits per unit of permissive area in control areas around the world in the same way that grade and tonnage frequencies are models of sizes and qualities of undiscovered...
Authors
Donald Singer, Vladimir Berger, W. Menzie, Byron Berger

Statistical guides to estimating the number of undiscovered mineral deposits: an example with porphyry copper deposits Statistical guides to estimating the number of undiscovered mineral deposits: an example with porphyry copper deposits

Estimating numbers of undiscovered mineral deposits is a fundamental part of assessing mineral resources. Some statistical tools can act as guides to low variance, unbiased estimates of the number of deposits. The primary guide is that the estimates must be consistent with the grade and tonnage models. Another statistical guide is the deposit density (i.e., the number of deposits per...
Authors
Donald Singer, W. D. Menzie

Chapter I: Geology of a Middle Tertiary Clay Deposit in thePatagonia Mountains near Harshaw, Santa Cruz County, Southeastern Arizona Chapter I: Geology of a Middle Tertiary Clay Deposit in thePatagonia Mountains near Harshaw, Santa Cruz County, Southeastern Arizona

A middle Tertiary rhyolite tuff on the northeast side of the Patagonia Mountains in Santa Cruz County, southeastern Arizona contains lenses of calcareous low-swelling montmorillonite clay, as much as 10 to 15 m thick. The presence of the tuff has been known for years, but the clay has not been described previously. The clay lenses, which are virtually silt- and sand-free, were probably...
Authors
Brenda Houser

Origin of the Bering Sea salient Origin of the Bering Sea salient

Our investigations in Alaska and Russia show that the curved orogen of the Bering Strait region is a composite feature that formed as a result of multiple superimposed events and cannot be related to latest Cretaceous–early Tertiary east-west shortening. Relations interpreted to record east-west shortening include the Chukchi syntaxis, deformation on Seward and Chukotka Peninsulas, the...
Authors
J.M. Amato, J. Toro, Thomas Moore

Preliminary report on using imaging spectroscopy to map ultramafic rocks, serpentinites, and tremolite-actinolite-bearing rocks in California Preliminary report on using imaging spectroscopy to map ultramafic rocks, serpentinites, and tremolite-actinolite-bearing rocks in California

Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) data were collected in approximately 3- kilometer-wide swaths over selected areas in El Dorado and Plumas Counties that contain serpentinite and ultramafic rocks as part of an experiment to determine if potentially asbestos-bearing rocks could be identified spectrally. M ineral maps created from the AVIRIS data were used...
Authors
Gregg Swayze, Chris Higgins, John Clinkenbeard, Raymond F. Kokaly, Roger Clark, Gregory Meeker, Stephen Sutley
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