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Stable Isotopic Evidence for the Rise of Oxygen and Reorganization of the Sulfur Cycle from the ca. 2.3 Ga Duitschland Formation, South Africa
(2006-12-13)
Metasedimentary rocks from the Transvaal Supergroup, South Africa, were used in a stable isotopic study to investigate the evolution of the Earth's early atmosphere and early biogeochemical cycles. Sulfur isotopic evidence ...
Floods, Hurricanes and Climate: Influences on the Potomac River Basin
(2008)
The suggestion from preliminary analysis of data derived from stream gauges in the Potomac River Basin is that tropical storm types generate many of the high magnitude flood events in the Potomac River Basin. The goals ...
DETERMINATION OF SULFUR ISOTOPE COMPOSITION IN SULFATE FROM TWO HIGH ELEVATION SNOWPITS BY MULTI-COLLECTOR THERMAL IONIZATION MASS SPECTROMETRY USING A DOUBLE SPIKE
(2005-05-12)
The variability of stable sulfur isotopes in nature provides a chemical tool for tracing the various sources of sulfur and a useful tool for understanding the sulfur cycle. It is also well established that snow and ice ...
Topographic signatures in the Himalaya: A geospatial survey of the interaction between tectonics and erosion in the Modi Khola valley, central Nepal
(2009)
Spurred by the recognition that lithologic resistivity to erosion influences the steepness of terrain, the purpose of this study is to enhance our understanding of feedbacks between erosion and tectonics in the Himalaya. ...
Gold distribution in the Archean Tanzanian Craton: Evaluating the effects of intracrustal differentiation
(2013)
This study evaluates the vertical distribution of gold in the continental crust. Implementing a recently published method by Pitcairn et al. (2006a) for the chromatographic separation of gold from acid-digested rocks using ...
The tectonics of intraplate regions: Quantifying stress and surface deformation in the central and eastern U.S. and planetary analogs on Mercury and the Moon
(2013)
Occurring ~ 1 year apart, the magnitude 3.4 Germantown, Maryland, (16 July 2010) and magnitude 5.8 Mineral, Virginia, (23 August 2011) earthquakes rocked the U.S. national capital region, drawing renewed attention to the ...
The role of mechanical mixing in the formation of reaction zones in subduction-related melange
(2013)
Traverses across metamorphic reaction zones at contacts between mafic rocks and ultramafic mélange matrix were analyzed in two mélange zones (Catalina Schist, Santa Catalina Island, CA, and Attic-Cycladic ...
Diffusion of Oxygen and Lithium Isotopes at a Contact between the Bushveld Complex and Metasedimentary Rock: Implications for the Timescale of Phepane Dome Diapirism
(2009)
Within the Eastern Lobe of the Bushveld Complex, the Phepane Dome is a circular structure of metasedimentary rock hypothesized to have formed as a wallrock diapir. To constrain the duration of Phepane Dome formation using ...
Forensic Geology in the Urban Environment: An Assessment of Material Transfer Behavior
(2013)
Soils and related anthropogenic materials are encountered as evidence in criminal investigations. The aim of this study was to better our understanding of soil transfer behavior in an urban environment, and to evaluate the ...
A Time-Series Geochemical Study of the ca. 2.5 Ga Batatal Formation in Brazil: Sulfur and Carbon Isotopic Insights into Environmental Conditions before the Great Oxidation Event
(2013)
Neoarchean metasedimentary rocks from the Batatal Formation, Brazil were studied using petrographic, elemental and stable isotopic techniques to provide a better understanding of coupling between the atmosphere-ocean system ...