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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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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...