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Browsing by Subject "Geochemistry"
Now showing items 1-18 of 18
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A Reconstruction of Precipitation and Hydrologic Variability on the Peruvian and Bolivian Altiplano During the Late Quaternary
(2012)The Peruvian/Bolivian Altiplano is an important hydrologic system for paleoclimate reconstruction because it is unique in its ability to record climate variability associated with the near-continental scale South American ... -
Biomarkers of Exposure: Arsenic Concentrations in Keratin in Populations Exposed to Arsenic in Drinking Water
(2014)Arsenic (As) exposure via groundwater consumption is a global health problem affecting millions. Monitoring exposure is a key step in understanding and predicating future health outcomes. This thesis explores the relationships ... -
From Layered Intrusions to Mid-Ocean Ridges: The Petrography and Geochemistry of Basaltic Magmas
(2020)The geochemical evolution of basaltic magmas, in a variety of settings, has been the subject of countless studies. In some instances, basaltic magmas evolve to form economic transition and precious metal ore bodies. The ... -
Geochemical and Isotopic Characterization of Coal Combustion Residuals: Implications for Potential Environmental Impacts
(2012)Coal fired power plants are ubiquitous in the United States and most developed countries around the world, providing affordable electricity to consumers. In the US, approximately six hundred power plants generate 136 million ... -
Geochemistry of Dikes and Lavas from Tectonic Windows
(2007-07-18)Tectonic windows are faulted escarpments that expose extensive sections of in situ oceanic crust, providing valuable opportunities to examine upper crustal architecture from a perspective unmatched by other approaches. Recent ... -
Identifying water contamination from fossil fuel development using geochemical and isotopic fingerprints
(2017)Fossil fuels continue to be a major component of the energy economies in North America, accounting for 60% of electricity generation in the U.S. Recent incidences (i.e. spills) and limited regulation of the fossil fuel industry ... -
Late Quaternary Paleoclimatology and Paleoceanography of the Amazon Continental Margin, Brazil
(2012)The tropics are a significant source of heat and moisture export, which drive global circulation patterns, thus it is vital to systematically understand the land, ocean and sedimentological interactions within the tropics. ... -
Radioactivity of Fossil Fuel Waste Products and Associated Environmental Implications
(2018)Extraction of energy resources and energy production can redistribute and concentrate naturally occurring radioactive materials (NORM), particularly from the uranium (238U t1/2=4.5 x 109 yr) and thorium (232Th t1/2=1.4 x ... -
Radium Isotope Geochemistry in Groundwater Systems: The Role of Environmental Factors
(2011)Prior studies of groundwater systems have associated increasing salinity and anoxic conditions with increasing radium (Ra) activities in water due to the decreasing effectiveness of Ra removal processes. However, the components ... -
Radium Isotopes as Tracers of Groundwater-Surface Water Interactions in Inland Environments
(2011)Groundwater has an important role in forging the composition of surface water, supplying nutrients crucial for the development of balanced ecosystems and potentially introducing contaminants into otherwise pristine surface ... -
Recovery of Rare Earth Elements from Coal Combustion Ash: Survey, Extraction, and Speciation
(2018)This research explores the beneficial reuse of coal combustion fly ash as a source of rare earth elements (REE). We characterized fly ashes of varied geological origin, tested several extraction methods and parameters, and ... -
Sulfide and Accessory Mineral Assemblages in the Sulfur-Poor Regions of the Stillwater Complex, Montana, USA
(2014)Layered igneous intrusions such as the Stillwater Complex in Montana contain the most economic concentrations of platinum-group elements (PGE) in the world, yet the processes involved in the enrichment of these PGE remain ... -
The origin of high Cu/S sulfides in the Skaergaard Intrusion, East Greenland
(2017)The Skaergaard Intrusion of East Greenland is unusual in that the trace sulfide assemblage is characterized by unusually high Cu/S ratios, containing abundant chalcopyrite and bornite (Cu5FeS4), the latter otherwise rare ... -
The Water-Energy Nexus for Hydraulic Fracturing
(2019)The water energy nexus represents the intersection of water use, energy production, electricity generation, and waste generation and disposal. The rapid rise of unconventional natural gas and oil production through the combined ... -
Tracing Anthropogenic Metal(loid) Contaminants in the Environment Using Geochemical, Radiogenic, and Radioactive Isotopic Tools
(2023)Coal combustion residuals (CCRs or coal ash), phosphate rocks and fertilizers, and leaded gasoline and lead-based paint represent major anthropogenic sources of metal and metalloid (i.e., metal(loid)) contaminants released ... -
Tracing hydraulic fracturing fluids and formation brines using boron, radium, and strontium isotopes
(2013)Production of oil and gas from unconventional natural gas reservoirs such as impermeable organic-rich shale formations was made possible through the use of horizontal drilling and high volume slick water hydraulic fracturing ... -
Using Large Layered Intrusions as Analogues for Understanding Subduction Zone Hydrothermal Systems
(2022)The genesis of layered intrusions has been the focus of countless studies. Layered intrusions have historically been viewed as natural laboratories to understand the evolution of a single large magma chamber. Many contain ... -
Water Management in Rural East Indonesia
(2019-04-26)This Master Project investigates the water quality of forty-six villages across four islands in remote East Indonesia. The major objective of this thesis is to test if naturally occurring heavy metal contamination affects ...
