Browsing Earth and Space Sciences by Title
Now showing items 51-70 of 120
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Landscape Response to Oblique Convergence: Insights from Numerical Modeling and from the Marlborough Fault System, New Zealand
Strike-slip and oblique faults are prominent tectonic features that can dramatically influence the landscape at all scales. In this dissertation, I explore the effects of strike-slip and oblique faults on the landscape, ... -
Landslides in Cascadia: Using geochronometry and spatial analysis to understand the timing, triggering and spatial distribution of slope failures in the Pacific Northwest United States
Landslides kill hundreds to thousands of people every year, cause billions of dollars in infrastructure damage, and act as important drivers of landscape evolution. In the Pacific Northwest USA, landslides routinely block ... -
Large woody debris and river morphology in scour pool formation, dam removal, and delta formation
The interactions between large woody debris, fluid flow, and sediment transport are a first-order control on river processes, affecting channel morphology at multiple scales. This thesis investigates how wood geometry and ... -
Magnesium isotope fractionation associated with biotic and abiotic weathering -and- Developing a scalable method for rare earth element extraction from non-traditional feedstocks using engineered Escherichia coli
This dissertation is divided into two sections, with the first discussing magnesium (Mg) isotope behavior during biotic and abiotic rock weathering, and the second describing the application of engineered microbes for the ... -
Mars' Water Cycle Seen Through an Ice Lens
The water cycle of Mars has been intensely studied thanks to data from orbiting spacecraft and landers on the surface. Water is of major interest due to its vital connection to life on Earth. The global cycle is driven by ... -
Measured and modeled albedos of sea-ice surfaces with implications for Snowball Earth
The Snowball Earth episodes were extensive glaciations that occurred during the Neoproterozoic, between 600 and 800 million years ago, during which ice covered much or all of the oceans. These glaciations were a result of ... -
Melt-Triggered Seismic Response in Hydraulically-Active Polar Ice: Observations and Methods
(2014-02-24)Glacier ice responds to environmental forcing through changes in its sliding speed and mass balance. While these changes often occur on daily time scales or longer, they are initiated by brittle deformation events that ... -
Micro-X-ray Fluorescence Mapping Data Analysis and Interpretation
The Planetary instrument for X-ray Lithochemistry (PIXL) is a micro-XRF instrument on NASA’s Perseverance rover. XRF has long been used for analyzing geologic materials, but instrumentation is constantly evolving and ... -
Modeling firn densification through viscosity and microstructures
Knowledge of firn densification is important for several applications, such as for ice-sheet surface elevation changes from repeat satellite altimetry methods used to estimate ice-sheet contribution to sea-level rise. ... -
Modeling global cosmogenic nuclide production rates through first principles
(2013-11-14)The work contained in this thesis is focused on utilizing radiation transport code software as the basis for developing a well validated, first-principles model of global terrestrial cosmogenic nuclide production rates. ... -
Novel studies of McMurdo Dry Valleys ice-cemented permafrost cores document chemical weathering in permafrost and the timing of Plio-Pleistocene glaciations
The McMurdo Dry Valleys (MDV) are a frigid, hyperarid desert of Antarctica with a landscape dominated by ice-rich permafrost. This research focuses on using two ice-rich permafrost cores collected from the MDV to study ... -
Nutrients, Productivity, and Redox Conditions during Greenhouse Extinctions in the Panthalassic Ocean
This study aims to better understand the series of events leading up to and following the Permian-Triassic mass extinction as it took place in the Panthalassic Ocean basin, with a particular focus on the oceanographic ... -
On Star-Planet Interaction: Magnetospheric Dynamics and Atmospheric Evolution
With the explosion of exoplanetary discoveries, the question of planetary habitability is at the forefront, and generates many interesting and complex questions. One of those questions: Are planetary global magnetic fields ... -
On the kinematic and dynamic evolution of a magma mush: from liquidus to solidus
Magmas are dynamic hydrogranular systems where the interactions between the melt and the residing crystals influences the eruptive behavior of volcanoes, the concentration of economic metals, and the stratification of the ... -
On the origin of Umtanum Ridge: kinematics of Neogene slip
(2014-04-30)Constraining the geometry of active faults is an important step in determining accurate estimates of regional seismic hazard. Where subsurface data are lacking, the shape of hanging wall folds can be used to interpret fault ... -
The Paleocene Eocene Thermal Maximum in the Hanna Basin, WY: Constraints from Organic Carbon Isotopes and Palynological Data
(2014-02-24)The P-E boundary, approximately 56 Ma, coincides with a global climatic event, the Paleocene-Eocene Thermal Maximum (PETM). The PETM is believed to have resulted from a 2-8 fold increase in atmospheric pCO2 in less than ... -
The persistence of rapid exhumation in the eastern Himalayan syntaxis
At the eastern margin of the Indian-Eurasian plate collision, margin-normal plate convergence transitions to dextral strike-slip motion, warping tectonic units southward to form the eastern Himalayan syntaxis. Large southeast ... -
The persistence of rapid exhumation in the eastern Himalayan syntaxis
At the eastern margin of the Indian-Eurasian plate collision, margin-normal plate convergence transitions to dextral strike-slip motion, warping tectonic units southward to form the eastern Himalayan syntaxis. Large southeast ... -
Physical Abrasion of Mafic Minerals and Basalt Grains: Application to Martian Aeolian Deposits
Sediment maturity, or the mineralogical and physical characterization of sediment deposits, has been used to locate of sediment source, transport medium and distance, weathering processes, and paleoenvironments on Earth. ... -
Physical Abrasion of Mafic Minerals and Basalt Grains: Application to Martian Aeolian Deposits
Sediment maturity, or the mineralogical and physical characterization of sediment deposits, has been used to locate of sediment source, transport medium and distance, weathering processes, and paleoenvironments on Earth. ...