Two studies concerning low molecular weight organic acids in soils were conducted. In the first study, anion exclusion chromatography was used to separate and identify 12 common organic acids, and the accuracy, precision and detection limits of the method were determined. The method was found to be sensitive and accurate...
This thesis investigates the influence of early diagenesis on trace metal and
molybdenum isotope behavior in marine and lacustrine environments. Chapter one is a
synthesis of previous research in all the marine environments investigated, providing an
essential geochemical context for interpreting the observed behavior of Mo in these settings.
Chapter...
Volatile hydrophobic compounds (HOCs) brought into soil and sediment
systems represent a serious threat to the environment. Dissolved
organic carbon (DOC) may exert an important influence over the total
aqueous solubility and mobility of organic pollutants through their
incorporation into micelles or the formation of soluble complexes.
To date, however,...
Determination of the source and fate of natural (higher plant lipids, marine
lipids, etc.) and anthropogenically (e.g., petroleum, coal emissions) derived
hydrocarbons and oxygenated compounds in the environment was accomplished
using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS)
to characterize or identify molecular biomarkers to be utilized as tracers....
Marine microorganisms play a significant role in the cycling of nutrients in the open ocean through production, consumption, and degradation of organic matter (OM). Carbon (C), nitrogen (N), and phosphorus (P) are essential ingredients in every known recipe for life. However, the cycling of each of these elements proceeds at...
This study was initiated to characterize the distribution of Fe-Mn nodules and to elucidate trends of Fe, Mn, and P relative to the intensity of the annual cycles of reduction and oxidation. Nodules were enriched in Fe, Mn, and P relative to the soil matrix making them an integral part...
Understanding continental crust formation and modification is a fundamental and longstanding geologic problem. Influx of mantle-derived basaltic magma and partial melting of the crust are two ways to drive crustal differentiation. This process results in a low density upper crust and denser, more refractory lower crust, creating significant and vastly...
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3. Isotopic (O, Sr, Nd, Pb, Hf) Geochemistry of Age-progressive Rhyolites
from the
