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Full-Text Articles in Physical Sciences and Mathematics
Sulfur And Trace Metal Cycling At Convergent Margins, Jesse B. Walters
Sulfur And Trace Metal Cycling At Convergent Margins, Jesse B. Walters
Electronic Theses and Dissertations
Subduction zones are the site of long-term chemical exchange between Earth’s surface and interior geochemical reservoirs. Subducting slabs are progressively depleted in volatiles and other mobile elements through dehydration and melting reactions. These elements are then introduced to the mantle wedge and volcanic arc. One consequence of this cycle is that volcanic arcs produce the most oxidized magmas on Earth. Sulfur, which exhibits a range in valence states from S2- to S6+, is one of the few elements in the subducting slab capable of oxidizing the arc and mantle wedge. Sulfides in the slab may also act …
Variations In The Southern Hemisphere Westerlies Over The Last 23,000 Years From Lake Records In The Falkland Islands, Meghan M. Spoth
Variations In The Southern Hemisphere Westerlies Over The Last 23,000 Years From Lake Records In The Falkland Islands, Meghan M. Spoth
Electronic Theses and Dissertations
The Southern Hemisphere Westerlies (SHW) are an important driver of climate in the mid-latitudes of the Southern Hemisphere. Abrupt latitudinal migration of this coupled atmospheric-oceanic system is thought to be linked to the onset of the Termination at the end of the last ice age and to subsequent climatic variation through the late-glacial period and Holocene. However, the timing and spatial extent of these shifts, as well as variations in wind intensity, are poorly constrained, hindering our understanding of abrupt climate change in the Southern Hemisphere. In addition, future changes in the position and intensity of the SHW are a …
A Groundwater Flow Model To Aid In Water Resource Management For The Carraipia Basin In The Coastal Semi-Arid Region Of La Guajira State (Colombia), Efren D. Gomez Arevalo
A Groundwater Flow Model To Aid In Water Resource Management For The Carraipia Basin In The Coastal Semi-Arid Region Of La Guajira State (Colombia), Efren D. Gomez Arevalo
Electronic Theses and Dissertations
About 160,000 inhabitants live in the 1,600 square kilometers Carraipia River Basin located in northeastern Colombia and northwestern Venezuela. Historically, water has been supplied to the inhabitants in this arid coastal region by shallow dug wells. Water supplied by these wells is frequently of poor quality due to high concentrations of total dissolved solids (TDS). Recently, due to the increasing demand for water, numerous deep wells have been drilled in the region to supply water to rural and urban areas from deep aquifers. Colombian agencies seek more quantitative information on groundwater resources, driven by increasingly severe water shortages over the …