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Browsing Earth and Space Sciences by Title
Now showing items 91-110 of 120
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Tectonics as recorded by thermochronometry, deformed datums, and submarine landscapes in western North America
Since the Mesozoic, the west coast of North America has experienced near continuous right-lateral shear. Over this time, a series of exotic crustal terranes accreted to and translated along the expanding westward edge of ... -
Terrestrial Paleoclimate of the Cenozoic: Insights from and Developments of the Soil Carbonate Clumped Isotope Thermometer
Land temperature at the surface of the Earth is a first-order parameter used to describe climate, but reliable and widespread measurements of this basic parameter through geologic time has eluded geochemists and geologists ... -
Testing the theory of radiation belt electron loss by hiss and electromagnetic ion cyclotron waves
Hiss, chorus and electromagnetic ion cyclotron waves (EMIC wave) are three major wave modes that are widely investigated and included in the radiation belt electron models to explain electron precipitation. The quasi-linear ... -
Testing thermal viscous remanent magnetization (TVRM) as a tool to date geomorphic events
When a rock forms, it acquires a thermal remanent magnetization (TRM) aligned with Earth's magnetic field. If the rock becomes misaligned with the magnetic field (by e.g. rockfall or glacial plucking and deposition), it ... -
The co-evolution of life and the nitrogen cycle on the early Earth
Nitrogen is an essential element for all life as we know it. Its abundance and speciation in the atmosphere and ocean has been dynamic through Earth’s history. The dynamic nature of nitrogen cycling is invariably linked ... -
The Formation and Evolution of Habitable Worlds
The next generation of ground- and space-based telescopes will probe the atmospheres, and possibly the surfaces, of Earth-sized planets in the habitable zone (HZ). However, observing time will be both expensive and limited ... -
The history, hydraulics, and geomorphic impact of outburst floods in the eastern Himalaya
Outburst floods have shaped many landscapes on Earth and represent a significant geologic hazard, but they are relatively infrequent, and we must rely on the sedimentary record to study the most extreme events that have ... -
The influence of meltwater on the thermal structure and flow of the Greenland Ice Sheet
As the climate has warmed over the past decades, the amount of melt on the Greenland Ice Sheet has increased, and areas higher on the ice sheet have begun to melt regularly. This increase in melt has been hypothesized to ... -
The legacy of megafloods in the eastern Himalaya: from erosion to deposition
Glacial lake outburst megafloods are infrequent, high magnitude (discharge ≥10^6 m^3/s) events that are uniquely efficient agents of landscape change, despite being short lived. Much of our understanding of megaflood ... -
The Okanogan lobe and Moses Coulee during the last glaciation
This thesis examines last-glacial chronologies of the Okanogan lobe of the Cordilleran Ice Sheet and explores whether this glacier released floods. The findings include age ranges for ice advance and retreat across the ... -
The Role of Corals on Tsunami Dynamics in an Island Setting: A Case Study of Tutuila Island
On September 29, 2009 at 17:48 UTC, an Mw = 8.1 earthquake in the Tonga Trench generated a tsunami that caused heavy damage across Samoa, American Samoa, and Tonga. One of the worst localities hit was the volcanic island ... -
Thermal regime and sublimation rates of subsurface ice in Antarctica and on Mars under current and past environmental conditions: Insights from modeling and ground data
Subsurface ice is common in regions where mean annual temperatures are below the freezing point of water. Once present, this ice may persist for long periods of time even under unfavorable environmental conditions. Subsurface ... -
Thermal-infrared radiosity and heat-diffusion model for estimating sub-pixel radiant temperatures over the course of a day
(2012-09-13)In temperature/emissivity estimation from remotely measured radiances the general assumption is that scene elements represented by pixels in fact have a single emissivity spectrum and are isothermal. Thus, estimated ... -
Thermodynamic Controls on the Global Ocean Overturning Circulation
This dissertation explores the fundamental relationship between the spatial distribution of air-sea flux and the structure of the ocean's Global Overturning Circulation (GOC). The GOC describes the circulation of ocean ... -
Thermodynamics of Acidophiles: Energetics of microbial growth, response to substrate availability, and interactions with heavy metals
Chemical and physical properties play a crucial role in the type and efficiency of microbial activity that can be supported within an ecosystem. In return, the presence of microbial activity affects the surrounding ... -
Tracing subduction zone processes with magnesium isotopes
Subduction and recycling of oceanic plates change the chemical composition of mantle and affect its physical properties, thereby modulating Earth’s dynamics. Stable Mg isotopes (δ26Mg) can trace this recycling process as ... -
Tsunamis and sea levels of the past millennium in Puget Sound, Washington
Tidal marsh deposits in the Puget Sound area contain evidence for multiple earthquakes and tsunamis over the past 1,000 years. This dissertation focuses on evidence beneath a salt marsh at Lynch Cove, at the head of the ... -
U/Pb ages of Eocene and younger rocks of the eastern flank of the central Cascade Range, Washington, USA.
(2013-04-17)Geological units located on the eastern flanks of the central Cascade Range, the Summit Conglomerate of Natapoc Mountain, Sugarloaf Peak, Basalt Peak, Horse Lake Mountain, Pole Ridge, Wenatchee Dome at the Cannon mine, and ... -
Uncertainty and Resolution in Full-Waveform, Continuous, Geoacoustic Inversion
(2013-11-14)The ocean geoacoustic inverse problem is the estimation of physical properties of the ocean bottom from a set of acoustic receptions in the water column. The problem is considered in the context of equipment and spatial ... -
Understanding Antarctic ice-stream flow using ice-flow models and geophysical observations
Ice streams are the primary pathway by which Antarctic ice is evacuated to the ocean. Because the Antarctic ice sheets lose mass primarily through oceanic melt and calving, ice-stream dynamics exert a primary control on ...