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Article
Open AccessElevated radium levels in Nubian Aquifer groundwater of Northeastern Africa
The Nubian Sandstone Aquifer System in Northeast Africa and the Middle East is a huge water resource of inestimable value to the population. However, natural radioactivity impairs groundwater quality throughou...
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Article
Open AccessOxidation induced strain and defects in magnetite crystals
Oxidation of magnetite (Fe3O4) has broad implications in geochemistry, environmental science and materials science. Spatially resolving strain fields and defect evolution during oxidation of magnetite provides fu...
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Article
Open AccessReal-time observation of cation exchange kinetics and dynamics at the muscovite-water interface
Ion exchange at charged solid–liquid interfaces is central to a broad range of chemical and transport phenomena. Real-time observations of adsorption/desorption at the molecular-scale elucidate exchange reacti...
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Article
Chlorine isotopic composition of perchlorate in human urine as a means of distinguishing among exposure sources
Perchlorate (ClO4−) is a ubiquitous environmental contaminant with high human exposure potential. Natural perchlorate forms in the atmosphere from where it deposits onto the surface of Earth, whereas synthetic pe...
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Article
Groundwater movement, recharge, and perchlorate occurrence in a faulted alluvial aquifer in California (USA)
Perchlorate from military, industrial, and legacy agricultural sources is present within an alluvial aquifer in the Rialto-Colton groundwater subbasin, 80 km east of Los Angeles, California (USA). The area is ...
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Article
Continental degassing of 4He by surficial discharge of deep groundwater
Helium-4 is produced in the Earth’s crust and degassed to the atmosphere. Measurements of 4He and 81Kr dating in an aquifer in Brazil suggest that most crustal 4He reaches the atmosphere by the discharge of deep ...
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Chapter
Isotopic Tracing of Perchlorate in the Environment
Isotopic measurements can be used for tracing the sources and behavior of environmental contaminants. Perchlorate (ClO 4 − ) has been detected widely in groundwater, soils, fertilizers, plants, milk, and human ur...
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Chapter
Stable Isotopic Composition of Chlorine and Oxygen in Synthetic and Natural Perchlorate
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Article
Nano-SIMS Analysis of Mg, Sr, Ba and U in Natural Calcium Carbonate
Concentrations of minor (Mg and Sr) and trace (Ba and U) elements in four natural calcium carbonate samples were first analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after chemical dissoluti...
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Article
Stable chlorine intramolecular kinetic isotope effects from the abiotic dehydrochlorination of DDT
Intention, Goal, Scope, Background. Identifying different sources and following reaction pathways of chlorinated organic contaminants in the environment can be challenging, especially when only their concentra...
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Article
Synchrotron X-ray Scattering Studies at Mineral-Water Interfaces
Synchrotron X-ray scattering techniques provide a powerful tool for the in situ study of atomic scale processes occurring at solid-liquid interfaces. We have applied these techniques to characterize and study rea...
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Article
The hydrothermal system of Volcan Puracé, Colombia
This paper presents chemical and isotopic data for thermal waters, gases and S deposits from Volcan Puracé (summit elevation ∼4600 m) in SW Colombia. Hot gas discharges from fumaroles in and around the summit ...
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Article
The hydrothermal system of Nevado del Ruiz volcano, Colombia
Hot springs and steam vents on the slopes of Nevado del Ruiz volcano provide evidence regarding the nature of hydrothermal activity within the summit and flanks of the volcano. At elevations below 3000 m, alka...
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Article
The origin of small-scale geochemical and mineralogic variations in a granite intrusion
A post-tectonic unzoned granite intrusion in the Meatiq Dome, a Late Proterozoic metamorphic complex in the Central Eastern Desert of Egypt, shows significant chemical and mineralogic heterogeneity on the scal...
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Article
Origin of low-18O metamorphic rocks from a Late Proterozoic shear zone in the Eastern Desert of Egypt
Anomalously low and variable 18O/16O ratios (whole rock δ 18OSMOW=−1.9 to +6.0) have been measured in several Late Proterozoic metamorphic units associated with a large scale low-angle ductile shear zone at Meati...
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Article
Behavior of Nuclear Waste Elements During Hydrothermal Alteration of Glassy Rhyolite in an Active Geothermal System: Yellowstone National Park, Wyoming
The behavior of a group of nuclear waste elements (U, Th, Sr, Zr, Sb, Cs, Ba, and Sm). during hydrothermal alteration of glassy rhyolite is investigated through geochemaical analyses of whole rocks, glass and ...
