Maps and models of seismic and tsunami risk are constructed from a variety of measurements taken in Indonesia, which have the potential to reduce loss of life and infrastructure. The first study uses the multichannel analysis of surface waves (MASW) method to calculate the time-…
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As major conduits for both water and sediment, rivers are responsible for shaping much of Earth's surface. The river morphology we observe today is result of complex interaction between geology, tectonics, climate, and erosion over time, an evolution that is recorded in sediment…
This dissertation presents results of an integrated approach including geochronology, paleomagnetism, petrography, x-ray diffraction analysis, depositional environment and sequence stratigraphic interpretation of Oligocene-age continental rift sediments. It provides a convincing…
Ocean models have been used to explain the reduction in atmospheric carbon dioxide concentration during the last glacial maximum; however, some models result in an intensification of bottom water reducing conditions. Redox-sensitive metals in sediments are potential constraints …
The effect of denitrification within continental margin sediments and suboxic water columns upon the isotopic composition of dissolved nitrogen was studied with the goal of constraining the present and past global oceanic "fixed" (forms other than N\sb2) nitrogen budgets. Sedime…
Speciation of sulfur and iron was investigated in the solid phase Black Sea sediments and high-temperature hydrothermal vent fluids of the 9°50'N East Pacific Rise and Lau Basin. Other than pyrite, solid phase sulfur in the upper Black Sea sediments existed as inorganic S(0) and…
Lake Matano of Indonesia, the 8th deepest lake on Earth, is an Fe-rich (ferruginous) end-member aquatic ecosystem and is the best known modern analogue for the ecology of Earth's earliest oceans. A culmination of geological, climatic and biological processes has resulted in an F…
Estimating the relative contribution of heavy metals and nutrients loads from diffuse and point sources and various hydrological pathways is a major research challenge in catchment hydrology. Understanding of the transfer, loads and concentration of these loads in basins is usef…
Basin and Petroleum System Modeling (BPSM) is coupled-physics approach that tracks over the course of basin history, the evolution of basin geometry, compaction, pressure, fluid flow, temperature, and chemical transformation of organic matter to quantitatively predict petroleum …
Two distinct studies within the Saltville Valley of southwestern Virginia revealed insights into local Pleistocene geology and paleontology. A variety of analytical techniques were applied to gravel deposits within the paleontological site of SV-5/7 that revealed this unit is ve…
Red siliciclastics and evaporites of Permian Nippewalla Group in mid-continental US were deposited in western equatorial Pangea. Previous studies of these rocks record Permian air temperatures as high as 73 °C, saline lake waters with a pH as low as ~1, and sedimentology that sh…
Soils provide numerous functions to support natural and human life. Soils and their functions develop over long timescales (decennia to millennia) under influence of environmental properties and drivers such as water flow, vegetation type and topography of the landscape. At the …
This project expands on the 4200-year history of Laguna Los Mangos by adding diatom analysis to existing records of pollen, charcoal, elemental composition, and stable light isotope analysis. Diatoms were counted in peroxide-treated samples, and data were analyzed using cluster …
Climate change is influencing the biogeochemical dynamics of lake systems in northern Canada. These changes may affect the loading and cycling of naturally occurring metal(loid)s and the long-term stability of mining-derived contaminants in sub-Arctic lakes. Arsenic (As) concent…
Paleolimnology offers insights into long-term perspective in freshwater ecosystems and is useful to fill gaps in historical limnological data. Using multiple indicators to reconstruct ecological trajectory of lakes may strengthen our comprehension of their ecology over long time…
Throughout the history of human-environmental interactions in Central America, the ancient Maya are one of the most contested regarding the extent to which their land-use strategies degraded their environment. For over 3500 years, the ancient Maya manipulated plant communities b…
Subduction zones host the world’s largest earthquakes, but seismic slip is only one style of deformation along the subduction interface. The deformation processes above and below the seismogenic zone are equally fundamental to understanding how relative motion is accommodated du…
The Giant Foresets Formation in the Taranaki Basin defines the present-day continental margin of the west coast of New Zealand’s North Island. Using regional 2D and 3D seismic datasets calibrated with exploration wells, this thesis presents a new highresolution seismic stratigra…
This project examines the role of plant diversity in the resilience and vulnerability of socioecological systems using an archaeological case study of the ancient Maya of the Mopan River valley, Belize. Archaeologists have documented major sociopolitical transformations in this …