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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: 2545

Niobium and tantalum: indispensable twins Niobium and tantalum: indispensable twins

Niobium and tantalum are transition metals almost always paired together in nature. These “twins” are difficult to separate because of their shared physical and chemical properties. In 1801, English chemist Charles Hatchett uncovered an unknown element in a mineral sample of columbite; John Winthrop found the sample in a Massachusetts mine and sent it to the British Museum in London in...
Authors
Klaus Schulz, John Papp

Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot

Siletzia is a basaltic Paleocene and Eocene large igneous province in coastal Oregon, Washington, and southern Vancouver Island that was accreted to North America in the early Eocene. New U-Pb magmatic, detrital zircon, and 40Ar/39Ar ages constrained by detailed field mapping, global nannoplankton zones, and magnetic polarities allow correlation of the volcanics with the 2012 geologic...
Authors
Ray Wells, David Bukry, Richard Friedman, Douglas Pyle, Robert Duncan, Peter J. Haeussler, Joe Wooden

Gemstones in 2013 Gemstones in 2013

No abstract available.
Authors
Donald W. Olson

Lithium in 2013 Lithium in 2013

No abstract available.
Authors
Brian W. Jaskula

Steady incision of Grand Canyon at the million year timeframe: A case for mantle-driven differential uplift Steady incision of Grand Canyon at the million year timeframe: A case for mantle-driven differential uplift

The Grand Canyon region provides an excellent laboratory to examine the interplay between river incision, magmatism, and the geomorphic and tectonic processes that shape landscapes. Here we apply U-series, Ar–Ar, and cosmogenic burial dating of river terraces to examine spatial variations in incision rates along the 445 km length of the Colorado River through Grand Canyon. We also...
Authors
Ryan S. Crow, Karl Karlstrom, Andrew Darling, Laura Crossey, Victor Polyak, Darryl E. Granger, Yemane Asmerom, Brandon Schmandt

Modified expression for bulb-tracer depletion—Effect on argon dating standards Modified expression for bulb-tracer depletion—Effect on argon dating standards

40Ar/39Ar geochronology depends critically on well-calibrated standards, often traceable to first-principles K-Ar age calibrations using bulb-tracer systems. Tracer systems also provide precise standards for noble-gas studies and interlaboratory calibration. The exponential expression long used for calculating isotope tracer concentrations in K-Ar age dating and calibration of 40Ar/39Ar...
Authors
Robert J. Fleck, Andrew T. Calvert

Compilation of gallium resource data for bauxite deposits Compilation of gallium resource data for bauxite deposits

Gallium (Ga) concentrations for bauxite deposits worldwide have been compiled from the literature to provide a basis for research regarding the occurrence and distribution of Ga worldwide, as well as between types of bauxite deposits. In addition, this report is an attempt to bring together reported Ga concentration data into one database to supplement ongoing U.S. Geological Survey...
Authors
Ruth F. Schulte, Nora K. Foley
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