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Sampling Of Soils With Metallic Residues Collected From Military Small-Arms Ranges, Jay L. Clausen

Doctoral Dissertations

Small-arms, artillery, mortar, and pyrotechnic military training introduces solid metallic residues into the environment. Previous energetic residue research showed conventional judgmental soil sampling and associated sample preparation methodologies are inadequate to address the heterogeneous distribution and still yield representative and reproducible results for the area of interest. Metallic residue deposition at military small-arms ranges occurs in a heterogeneous distributional pattern, similar to solid particulate energetic residue deposition.

One of the primary objectives of an environmental investigation is to estimate the mean contaminant concentration to evaluate human and ecological risk in an exposure unit (i.e., an area where the receptors are …

Metamorphism, Deformation, Geochemistry, And Tectonics Of Exhumed Ultramafic And Mafic Rocks In The Central And North-Central Vermont Appalachians, Ian Wiley Honsberger

Doctoral Dissertations

The Neoproterozoic to Early Paleozoic metamorphic, deformational, geochemical, and tectonic history of the Vermont Appalachians is preserved in ultramafic, mafic, and pelitic rocks exposed west of the Iapetan suture zone in the Green Mountain and Rowe Slices of Vermont. Whole-rock geochemical analyses of polymetamorphosed amphibole-bearing mafic rocks within this zone are consistent with subalkaline basalt/gabbro protoliths that varied regionally with respect to REE concentrations inherited during crystallization. The mafic rocks that are in contact with ultramafics preserve MORB signatures, while the mafic rocks that are not in contact with ultramafics preserve REE signatures that range from MORB and OIB to …

Quantifying Glacier Sensitivity To Late Glacial And Holocene Climate Changes In The Southern Peruvian Andes, Elizabeth Grace Huss

Master's Theses and Capstones

Tropical glaciers are highly sensitive to small-amplitude climate changes, implying that paleoglacier positions are valuable proxies for reconstructing paleoclimate conditions. However, it is still unknown how glaciers in different regions along the Andes responded to changes in specific climate parameters, and in particular, to changes in the dominating influences of temperature and precipitation. To identify the dominant controls on tropical paleoglacier mass balance, a surface energy balance model (SEBM), coupled with an ice dynamics model, was applied to three valleys in the Cordillera Vilcabamba of southern Peru. These valleys contain present-day glaciers and preserve evidence for the areal extents and …

The Relationship Between Volatiles (Co2, H2o, F, S & Cl) And Noble Gases In Reykjanes Peninsula Lavas, Iceland, Lorne Loudin

Master's Theses and Capstones

The presence of volatiles in the local mantle magma source region has been suggested as a contributor to the observed high melt production rates in the volcanic segments of the island of Iceland. However, the source of volatiles beneath this island remains enigmatic. New volatile (CO2, H2O, F, S and Cl) concentration data for 157 olivine-hosted melt inclusions in concert with noble gas data (He and Ne) from the Reykjanes Peninsula, Iceland, allow for the reconstruction of magma degassing and the distribution of volatiles in the mantle beneath Iceland. Water concentrations in olivine-hosted melt inclusions from this study record a …