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Uranium-series comminution ages of continental sediments: Case study of a Pleistocene alluvial fan

Description: Obtaining quantitative information about the timescales associated with sediment transport, storage, and deposition in continental settings is important but challenging. The uranium-series comminution age method potentially provides a universal approach for direct dating of Quaternary detrital sediments, and can also provide estimates of the sediment transport and storage timescales. (The word"comminution" means"to reduce to powder," reflecting the start of the comminution a… more
Date: April 30, 2010
Creator: Lee, Victoria E.; DePaolo, Donald J. & Christensen, John N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Isotopic Tracking of Hanford 300 Area Derived Uranium in the Columbia River

Description: Our objectives in this study are to quantify the discharge rate of uranium (U) to the Columbia River from the Hanford Site's 300 Area, and to follow that U down river to constrain its fate. Uranium from the Hanford Site has variable isotopic composition due to nuclear industrial processes carried out at the site. This characteristic makes it possible to use high-precision isotopic measurements of U in environmental samples to identify even trace levels of contaminant U, determine its sources, a… more
Date: October 31, 2010
Creator: Christensen, John N.; Dresel, P. Evan; Conrad, Mark E.; Patton, Gregory W. & DePaolo, Donald J.
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Partner: UNT Libraries Government Documents Department
open access

Pb Isotopes as an Indicator of the Asian Contribution to Particulate Air Pollution in Urban California

Description: During the last two decades, expanding industrial activity in east Asia has led to increased production of airborne pollutants that can be transported to North America. Previous efforts to detect this trans-Pacific pollution have relied upon remote sensing and remote sample locations. We tested whether Pb isotope ratios in airborne particles can be used to directly evaluate the Asian contribution to airborne particles of anthropogenic origin in western North America, using a time series of samp… more
Date: October 25, 2010
Creator: Ewing, Stephanie A.; Christensen, John N.; Brown, Shaun T.; Vancuren, Richard A.; Cliff, Steven S. & DePaolo, Donald J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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