Digital Commons Network^™

Lead And Arsenic Contamination In Urban Soils In New York City, Anna Paltseva

Dissertations, Theses, and Capstone Projects

This dissertation examined total and bioaccessible soil lead (Pb) and arsenic (As) concentrations and their accumulation in commonly grown garden vegetables in New York City (NYC) metropolitan area. Direct oral ingestion of contaminated soil and consumption of plants that have accumulated Pb or As from underlying soil are known human exposure pathways in urban garden soils that often contain elevated levels of contaminants. The research had four components: (1) assessment of the variability of bioaccessible Pb in NYC urban soils; (2) field experiments to evaluate Pb stabilization and As mobilization by phosphate and alternative amendments; (3) development of a new …

The Role Of Fluids In Ore Remobilization At The Balmat Zinc Deposit, Ny, Peter D. Matt

Dissertations, Theses, and Capstone Projects

Shear zone-hosted orebodies at the Balmat, NY, zinc deposit were remobilized at the kilometer scale during amphibolite facies regional metamorphism ca. 1180 Ma. Despite there being little evidence for interaction of hydrous fluids and ores during deformation, such translocation distances are considered unlikely without the assistance of fluids. Two independent research methods, SEM-EDS micro-petrography and zinc isotope geochemical analysis, demonstrate that anatectic sulfide and silicate melts were generated during metamorphism. Micro-petrography of the Fowler ore body reveals low melting-temperature micro-inclusions of sulfosalt and sulfide assemblages which occur predominantly in Qtz-Py and Kfs-Py domains that cross-cut peak metamorphic assemblages. These results …

The Water/Energy Nexus: Climate, Consumption And Ecosystem Services, Hildegaard D. Link

Dissertations, Theses, and Capstone Projects

Water and energy are drivers of living systems. This work provides an assessment of the Water Energy Nexus in the United States, comparing the well-watered north-east and the arid west. Electric grid systems are most stressed on hot summer afternoons. Grid stress can lead to cascading failures of electricity, water and wastewater treatment systems. (Zimmerman, 2017) Water for power generation and/or water supply depend on ecosystem services. The ecosystem services and resource trade-offs embedded in provision of a watt of power and an ounce of potable water, however, have yet to be comprehensively enumerated nor have the cost relationships been …

Abrupt Climate Transitions, Christine J. Ramadhin

Dissertations, Theses, and Capstone Projects

The Earth’s climate system displays a long history of nonlinear abrupt transitions which have resulted in significant ecosystem disruption and are recorded in the geologic data. Today significant anthropogenic changes are occurring in many Earth systems that seem to be pushing these toward critical thresholds. Thus, increasing the possibility of a transition to alternative states which can have unfavorable consequences. Therefore, it becomes compelling to forecast when and how these transitions will occur so that decision-makers can devise appropriate strategies to avoid or cope with the effects of a changeover to a new alternative state. However, due to the highly …

Oldowan Tool Behaviors Through Time On The Homa Peninsula, Kenya, Emma M. Finestone

Dissertations, Theses, and Capstone Projects

The adaptive significance of tool use to genus Homo is a central theme in human origins. However, what we know from the early Oldowan sites suggests that persistent technology may have begun as an opportunistic behavior with minimal investment, rather than a habitual and widespread adaptive revolution. This dissertation seeks to investigate investment in Oldowan tool production on the Homa Peninsula, Kenya, considering raw material selection, transport, and lithic production at two newly discovered Oldowan localities: Nyayanga (ca. 2.6 Ma) and Sare River (ca. 1.7 Ma).

The first section of this dissertation outlines a method that enables the comparison of …

Snowmelt Detection On Alpine Glaciers Using Synthetic Aperture Radar Time Series, Corey Scher

Dissertations and Theses

Hindu Kush Himalayan (HKH) glaciers serve as some of the most sensitive indicators of changes in global climate. These glaciers shape the hydrologic dynamics of river systems supplying freshwater to over 2 billion people throughout Asia and regulate the geochemistry of sensitive aquatic alpine ecosystems. As snowmelt onsets sooner, lasts longer, and snowfields retreat due to increases in global temperature, the hydrologic dynamics of catchments draining HKH threaten to change the availability of surface freshwater resources for nearly one fifth of the global population, disturb sensitive aquatic habitat, and precipitate hazards associated with glacier wasting. Informed planning and decision-making around …

Electrical Conductivity And Resistivity Study Of Heterogeneous Sediment In Inwood Hill Park, Manhattan, Ny, Rea A. Khaleda

Dissertations and Theses

The area near the inlet of Spuyten Duyvil Creek in Inwood Hill Park in New York City exhibits complex hydrological processes. The inlet is a tidal flat, which contains brackish water; a mixture of saltwater and freshwater. The area was modified by man, built on a shell bed and contains heterogeneous sediment. One field adjacent to the inlet contains several small sinkholes. Electrical resistivity and ground conductivity techniques were used in order to get an understanding of the hydrological processes of this field. It was hypothesized that the formation of the sinkholes is due to the tidal forcing of the …

Pressure, Temperature, And Stress Conditions Of Southern Alpine Fault (New Zealand) Mylonites, Jake T. Reitman

Dissertations and Theses

The Alpine Fault, New Zealand, provides a unique window into the rheologic history of a seismically-active continental plate boundary. Due to lower exhumation rates along southern portions of the fault relative to the well-studied central Alpine Fault, deformation ages vary along strike by ~15 m.y.. Mylonites collected from two southern creeks near Haast, NZ, display a uniform recrystallized grain size of ~11 𝜇m in mylonitic quartz indicating differential stress values in the south of ~100 MPa, roughly twice the stress values observed in the central Alpine Fault. Constraints from Ti-in-quartz thermobarometry and Raman Spectroscopy of Carbonaceous Material (RSCM) indicate mylonitization …

Carbonatites As A Record Of The Carbon Isotope Composition Of Large Igneous Province Outgassing, Ellen Gales

Dissertations and Theses

Large igneous province (LIP) eruptions have been linked in some cases to major perturbations of Earth’s carbon cycle. However, few observations directly constrain the isotopic composition of carbon released by LIP magmas because carbon isotopes fractionate during degassing, which hampers understanding of the relative roles of mantle versus crustal carbon reservoirs. Carbonatite magmatism associated with LIPs provides a unique window into the isotopic systematics of LIP carbon because the majority of carbon in carbonatites crystalizes rather than degassing. Here, we present new δ¹³C data for the Guli carbonatites in the Siberian Traps. In addition, we compile ~260 published …

Hydroclimate Drivers And Atmospheric Dynamics Of Floods, Nasser Najibi

Dissertations and Theses

Our preliminary survey showed that most of the recent flood-related studies did not formally explain the physical mechanisms of long-duration and large-peak flood events that can evoke substantial damages to properties and infrastructure systems. These studies also fell short of fully assessing the interactions of coupled ocean-atmosphere and land dynamics which are capable of forcing substantial changes to the flood attributes by governing the exceeding surface flow regimes and moisture source-sink relationships at the spatiotemporal scales important for risk management. This dissertation advances the understanding of the variability in flood duration, peak, volume, and timing at the regional to the …