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Full-Text Articles in Physical Sciences and Mathematics

Using Modflow To Assess Groundwater Storage Enhancement Via A Floodplain Infiltration Basin, Lindsay Henning Jan 2023

Using Modflow To Assess Groundwater Storage Enhancement Via A Floodplain Infiltration Basin, Lindsay Henning

All Master's Theses

Delaying groundwater discharge into rivers until it is critically needed during baseflow conditions provides promise for lowering elevated stream temperatures and improving habitat for aquatic species. Increasing groundwater storage may accomplish this in locations where excess spring runoff can be captured and allowed to infiltrate into the subsurface for later beneficial use, a process known as Managed Aquifer Recharge (MAR). Here, MAR via an infiltration basin is considered at a site along the Teanaway River in central Washington State. The effects of simulated ephemeral ponds of sizes varying from 554 m3 to 2430 m3 (0.449 acre-feet to 1.97 …


Estimating Evapotranspiration And Analyzing Soil Moisture And Heat Flux Parameters At Taneum Creek, Central Washington, Edward Vlasenko Jan 2023

Estimating Evapotranspiration And Analyzing Soil Moisture And Heat Flux Parameters At Taneum Creek, Central Washington, Edward Vlasenko

All Master's Theses

In the past two decades, stream restoration work, primarily in the form of wood emplacement, has been undertaken in the Taneum Creek watershed, resulting in increased channel-floodplain connectivity. One of the goals of stream restoration was to boost dry season groundwater storage in the shallow floodplain aquifer. However, any gains in groundwater due to increased connectivity may be nullified by increased evapotranspiration (ET) losses because of denser floodplain vegetation. Within the floodplain aquifer budget, ET is a major flow of water out of the system and is not well quantified.

In order to quantify ET, a monitoring site was established …


A Conceptual Framework For Managed Aquifer Recharge In The Columbia River Basalts Of The Lower Yakima River Basin, Bethany Kharrazi Jan 2023

A Conceptual Framework For Managed Aquifer Recharge In The Columbia River Basalts Of The Lower Yakima River Basin, Bethany Kharrazi

All Master's Theses

In the Yakima River Basin in south-central Washington, increasing demands for water, overallocation of surface water, and a changing climate are leading to a loss of water storage and increasing water deficits in drought years. A warming climate has reduced snowpack in the Cascade Range, a vital reservoir for the irrigated agricultural industry which supports the basin’s economy. Managed aquifer recharge (MAR) is a sustainable and cost-effective approach for securing water supply by storing water underground for recovery during drought. Diminishing groundwater levels in regional basalt aquifers over the last several decades suggest there is significant storage available for intentional …


Constraining Rock Type Controls On Geophysical Properties: Implications For Earthquake Hazard Assessment Near Ellensburg, Washington, Zachary Stevens Jan 2023

Constraining Rock Type Controls On Geophysical Properties: Implications For Earthquake Hazard Assessment Near Ellensburg, Washington, Zachary Stevens

All Master's Theses

High precision geophysical modeling can constrain the geometry of structures in the upper to middle crust beyond what is possible with surface data alone, which allows for a better understanding of seismic hazards. This modeling requires values of both the magnetic susceptibility and density relevant to rocks at depth; this study presents a combination of field and laboratory measurements of basement units to determine these properties. The basement rock of the Kittitas Valley is made up of a complex series of metamorphic and igneous bodies, so it was important to gather a representative suite of samples of the most volumetrically …


Paleoseismic Investigation Of Rupture On The Dead Coyote Fault In The Kittitas Valley, Washington, Garet Huddleston Jan 2023

Paleoseismic Investigation Of Rupture On The Dead Coyote Fault In The Kittitas Valley, Washington, Garet Huddleston

All Master's Theses

Recently discovered fault scarps along the Dead Coyote Fault (DCF) in the northern Kittitas Valley (KV) of central Washington suggests active faulting in the late Quaternary, but constraints on the timing and potential magnitude of earthquakes along the fault zone are limited. The KV lies at the northwestern edge of the Yakima Fold and Thrust Belt (YFTB), a low-strain region where individual structures are capable of producing M~7 earthquakes.

This investigation uses surficial geologic mapping and topographic analysis of the DCF scarps, ground penetrating radar transects, and paleoseismic trenching to determine the rupture history of the DCF. The trench was …


Hydrologic And Geomorphic Investigations Of Two Engineered Stream Crossings Under Interstate 90 In Washington State, Catherine Mast Jan 2023

Hydrologic And Geomorphic Investigations Of Two Engineered Stream Crossings Under Interstate 90 In Washington State, Catherine Mast

All Master's Theses

The importance of stream restoration in providing a healthy ecosystem is widely recognized. The Washington State Department of Transportation (WSDOT) has implemented environmental changes to facilitate habitat restoration and wildlife passage along the Interstate 90 Highway (I-90) corridor where it passes over the Cascade Mountains. Prior to the I-90 corridor expansion, Price and Noble Creeks passed under the highway though culverts, limiting passage of aquatic species or wildlife below the highway. In 2019 the stream channel crossings were expanded, and the size/shape of these creeks were engineered to mirror what would be seen in a natural environment. Since construction, erosion …


An Evolution Of Gold Of The Swauk Mining District, Liberty Washington, Timothy Miller Jan 2023

An Evolution Of Gold Of The Swauk Mining District, Liberty Washington, Timothy Miller

All Master's Theses

The Swauk Mining District in Central Washington state is a historic mining community with active small scale mining dating back to the 1870’s. Gold has been mined from both lode and placer deposits. The placer deposits of Liberty area are unique due to the variety of gold textures, most notably are the nuggets of tangled masses of dendritic crystals and wire gold.

This research aims to determine the paragenic sequence that led to the formation of the lode and placer gold deposits using a combination of field work and laboratory analyses. Field work consisted of small-scale detailed mapping, recording of …


Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett Jan 2022

Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett

All Master's Theses

Numerous stream restoration projects in the Yakima River Basin in Washington have placed large wood (LW) into tributary channels. One intended effect is to divert water onto floodplains to increase groundwater (GW) recharge and seasonal storage in shallow alluvial aquifers during spring high flows with the intention of releasing GW into streams during the drier summer months. Large wood was emplaced in the Indian Creek tributary of the Teanaway River in Kittitas County, Washington beginning in 2016. Potential changes in the groundwater recharge in the adjacent floodplain before and after the LW installation were investigated through stratigraphic analysis, stream-flow modeling, …


The Effects Of Channel Incision And Land Use On Surface-Water/Groundwater Interactions In The Teanaway River Basin, Washington, Usa, Joseph Petralia Jan 2022

The Effects Of Channel Incision And Land Use On Surface-Water/Groundwater Interactions In The Teanaway River Basin, Washington, Usa, Joseph Petralia

All Master's Theses

The Teanaway River basin, a major tributary to the Yakima River, is host to several restoration projects with the intention of returning the river channel to a more natural state and improving riparian habitat. These projects may also increase aquifer storage and potentially increase summertime streamflows. This study of the Teanaway Valley Family Farm, an 88-hectare parcel on the main-stem Teanaway River that was recently purchased by Washington Department of Fish and Wildlife, provides hydrogeologic data that will inform these restoration projects. Following the purchase of this land, ten wells were installed within and slightly above the floodplain in order …


Geomorphic History And Preservation Of Archaeologically Significant Areas In The Hanford Reach Of The Columbia River, Washington State, Benjamin Deans Jan 2022

Geomorphic History And Preservation Of Archaeologically Significant Areas In The Hanford Reach Of The Columbia River, Washington State, Benjamin Deans

All Master's Theses

Archaeological sites near rivers may be preserved through burial, altered by exposure, or destroyed through erosion. Preserved because of the unusual needs of the Manhattan Project, the Hanford Reach is the only remaining free-flowing reach of the Columbia River and ideal for research into the geomorphic settings of archaeological sites along this river. The 1894 (742,000 cfs [20,900 m3/s]) and 1948 (690,000 cfs [19,000 m3/s]) floods were the largest in the historical record through the reach, but their relationship with geomorphic change and site preservation are less understood. To understand how floods have preserved and destroyed …


Developing And Validating A Standard Operating Procedure For Quantitative Analysis Using Central Washington University's X-Ray Diffractometer, Katherine Lucas Jan 2022

Developing And Validating A Standard Operating Procedure For Quantitative Analysis Using Central Washington University's X-Ray Diffractometer, Katherine Lucas

Undergraduate Honors Theses

X-ray diffraction (XRD) is widely applied in a variety of disciplines to identify crystalline solids in a powdered sample. Recent software advances have made quantitative analysis of samples easier and more accessible, but the quality of the result depends on the sample preparation and data collection procedure. This project focuses on testing methods of sample preparation and XRD data collection and analysis to lay the groundwork for refinement of the existing standard operating procedures at CWU. First, I determined the ball mill grinding time necessary to powder different mineral samples. The addition of hand grinding to ball mill-ground samples produced …


Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. Demott Jan 2021

Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. Demott

All Master's Theses

The Elwha River once provided vital habitat for a variety of salmonid species, but after two dams were emplaced on the river in the early 1900s, habitat diminished, and salmon populations declined. From 2011-2014, the dams were finally removed to restore the Elwha ecosystem. To understand the long-term geomorphic impacts of the Glines Canyon Dam removal on the Elwha River, I quantified changes in four parameters: in-channel large wood, main channel sinuosity, channel braiding, and sedimentation. High-resolution imagery from 2012-2020 was used to map large wood and digitize main and secondary river channels, and field surveys were completed at study …


Tsunami Deposits And Tsunami Modeling Of The 900 Ad Seattle Fault Event In Northern Puget Sound, Andrew A. Raulerson Jan 2021

Tsunami Deposits And Tsunami Modeling Of The 900 Ad Seattle Fault Event In Northern Puget Sound, Andrew A. Raulerson

All Master's Theses

Puget Sound has a history of earthquakes and tsunamis with an ever-expanding knowledge of these events. The focus of this study is the Seattle fault earthquake and resulting tsunami 1100 years ago. This study aimed at refining the extent of tsunami inundation north of the fault using a two-phased approach: a field study at Elger Bay and tsunami modeling. Tsunami deposits dating to this event have been observed in six sites total sites in Puget Sound, and four of them are in northern Puget Sound. At Elger Bay I found one tsunami deposit in cores from the southwest corner of …


Late Holocene Paleoflood Hydrology Of The Snake River In The Lower Hells Canyon, Idaho, Kent C. Allen Jan 2020

Late Holocene Paleoflood Hydrology Of The Snake River In The Lower Hells Canyon, Idaho, Kent C. Allen

All Master's Theses

The Snake River watershed spans a large geographic region from the Rocky Mountains to the inland Pacific Northwest, and a comprehensive paleoflood chronology on the mainstem of the river is key to identifying the frequency and magnitude of large prehistoric floods within the region. We examined and compared four sites of slackwater deposits along a 20-km reach of the Lower Hells Canyon on the Snake River, Idaho. The sites contain evidence of up to 34 paleofloods within the last 1700 years. Stratigraphic breaks, soils, and in-situ plant or archaeological materials demarcate distinct layers that represent discrete paleoflood events. Radiocarbon dates …


Modeling Of Potential Historical Tsunamis From Large Earthquakes In The Izu-Bonin Mariana Subduction Zone, Rachelle Reisinger Jan 2020

Modeling Of Potential Historical Tsunamis From Large Earthquakes In The Izu-Bonin Mariana Subduction Zone, Rachelle Reisinger

All Master's Theses

The Izu-Bonin Mariana (IBM) subduction zone is an over 3000-km long oceanic-oceanic convergence zone with no instrumental record of great subduction-zone earthquakes (Mw > 8.0). Due to the lack of great earthquakes and the oceanic-oceanic subduction style, previous researchers have speculated that the IBM does not produce great earthquakes. The same behavior was also proposed for the northern Japan and Cascadia subduction zones, which has since been proven false. We use the tsunami model GeoClaw (v5.6.0) with adjoint-guided refinement level flagging to simulate IBM earthquakes in three separate segments to produce estimates of wave heights at locations around the Pacific …


Documenting The Earthquake History Of The Thousand Springs Fault In Summer Lake Basin, Oregon, Usa, Elizabeth Curtiss Jan 2020

Documenting The Earthquake History Of The Thousand Springs Fault In Summer Lake Basin, Oregon, Usa, Elizabeth Curtiss

All Master's Theses

Defining seismic hazards in low-strain-rate regions such as the northwestern Basin and Range can be difficult due to the infrequency of earthquakes. Revealing the earthquake records of low-strain-rate regions can refine our understanding of the variability of earthquake sizes and recurrence intervals, however, which can ultimately improve hazard analysis. Four active normal faults form the Summer Lake basin, in the northwestern Basin and Range: The Thousand Springs (TSF), Ana River (ARF), Slide Mountain, and Winter Ridge faults. Other than the TSF, the faults in the Summer Lake basin have documented histories that include surface-rupturing (>M6) earthquakes. Scarps along the …


Sampling The Local Fare: Fishes At The Sam Israel House Pit (45gr76), Soap Lake, Washington, Adam Fruge Jan 2020

Sampling The Local Fare: Fishes At The Sam Israel House Pit (45gr76), Soap Lake, Washington, Adam Fruge

All Master's Theses

The Sam Israel site is a precontact archaeological complex with numerous fish bones at the north end of Soap Lake, Washington. Excavated in 1976, the fish remains recovered from there were never fully analyzed prior to this research. Since this inland Columbia Plateau site had thousands of fish bones, it contained untapped potential for our understanding of ancient local fish procurement. As such, I conducted a detailed analysis of 2,862 fish bone specimens from the Sam Israel House Pit locus to: study a larger sample of fish bones in greater detail than was done before; compare the distribution of fishes …


Modeling Cle Elum Reservoir Shoreline Erosion: Gis Analysis To Support Cultural And Environmental Resource Management, Yakima Basin, Washington, Michael H. Horner Jan 2020

Modeling Cle Elum Reservoir Shoreline Erosion: Gis Analysis To Support Cultural And Environmental Resource Management, Yakima Basin, Washington, Michael H. Horner

All Master's Theses

In the Yakima Basin, managers are expanding reservoirs including Cle Elum Lake to increase the availability of water. The objective of this study was to examine areas prone to further shoreline erosion to inform resource management. This research included the use of airphotos and fieldwork to identify erosional shorelines. Erosion was verified in the field using a video survey as well as indicators such as shoreline slope, sediment size, and nearshore width. Near-term erosional segments were identified by more rapidly receding bluffs while long-term erosional segments included both bedrock cliffs and bluffs. Although most of the shoreline is depositional, near-term …


Recovering Lost Information From Avocational Projectile Point Collections, Mackenzie Hughes Jan 2020

Recovering Lost Information From Avocational Projectile Point Collections, Mackenzie Hughes

All Master's Theses

Human prehistory in North America has sparked the interest of private citizens for decades, sometimes leading to an accumulation of avocational artifact collections that lack site-level provenience. The Wild/Clymer artifacts (n = 1,371) are one such collection where precise site provenience was lost. The analysis aims to recover regional provenience by using morphology, raw material sourcing, and typology to create a data set. The avocational collection data set was analyzed by comparing it to the professionally recorded archaeological data sets from within 100 miles of Frenchglen, Oregon. A paradigmatic classification approach identified 606 typeable points in the avocational collection, in …


Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce Jan 2020

Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce

All Master's Theses

Coastal communities of Puget Sound are susceptible to tsunami inundation from multiple sources. Two sources of potential tsunami hazard that threaten the region are earthquakes on crustal faults in the Puget Lowlands, or earthquakes originating on the Cascadia subduction zone. This study investigated two coastal marshes in Puget Sound, Deer Lagoon and Doe-Kag-Wats, for evidence of a paleotsunami record to combine with tsunami modeling, in order to predict how future events could inundate Puget Sound. A deposit, interpreted as a paleotsunami, is traceable thought the marsh stratigraphy near the modern day tidal inlet of Deer Lagoon, a site that has …


Applying Garnet And Zircon Ree Linkages To Determine Timing Of P-T Conditions And Tectonic Implications For Uhp Eclogites And Hp Granulites, Dulan Uhp Terrane, China, Wesley Weisberg Jan 2020

Applying Garnet And Zircon Ree Linkages To Determine Timing Of P-T Conditions And Tectonic Implications For Uhp Eclogites And Hp Granulites, Dulan Uhp Terrane, China, Wesley Weisberg

All Master's Theses

The Dulan ultrahigh-pressure (UHP) terrane in western China hosts rocks that record continental collision, however; the timing of peak P-T conditions in UHP eclogites and HP granulites, and the tectonic significance of their spatial relationship within the Dulan UHP terrane are not well understood. This study, (1) evaluates rare earth element (REE) equilibrium between garnet and zircon, to assess coeval growth; (2) links timing (from zircon) to the P-T history (from garnet) to constrain the P-T-t path of the Dulan UHP terrane and interpret implications for zircon growth; (3) refines P-T conditions for HP granulite; and (4) evaluates the tectonic …


Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona Jan 2019

Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona

All Master's Theses

Records of past tsunamis help constrain the long-term characteristics of megathrust earthquakes and elucidate the role of sea-level in the preservation of tsunami deposits. Near Queule, south-central Chile (39.3˚S, 73.2˚W), three sand layers interpreted as tsunami deposits are interbedded with dark, organic-rich, silt deposits along a tidal channel landward of a sand spit capped by eolian sand dunes. The uppermost sand layer is attributed to the tsunami from the Mw 9.5 1960 earthquake. The sand layer is widespread, tabular, oxidized, thins landward, and generally occurs at a depth of <20 cm. The spatial distribution of the deposit corresponds closely with the extent of the 1960 tsunami sand on 1961 aerial photographs. We computed numerical simulations of the 1960 tsunami in Queule using the GeoClaw finite-slip hydrodynamic model based on three published earthquake sources. The simulations showed inundation up to 4km inland that overtopped the coastal dunes; agreeing with historical documentation and testimonies of 1960 tsunami survivors. Stratigraphically below the 1960 tsunami deposit are two tabular, landward-thinning sand layers with sharp lower contacts above silty organic-rich layers. Combined radiocarbon ages of seeds, charcoal and wood fragments found at the contacts with the underlying organic layers yielded ages of 5460-5320 and 5990-5910 cal. years BP. These sand layers have similar distribution patterns to the 1960 sand layer, but are finer grained, thinner and less oxidized. Below this sequence of interbedded tsunami sands and silty organic layers there is an abrupt contact underlain by a distinct sequence of four inorganic silt layers alternating with dark brown organic-rich silts, which are older than 6280-6110 cal. years BP. The deepest studied layer is a thick, fine, gray sand. We interpret the gray sand as a submarine environment during the mid-Holocene sea-level high stand, and the alternating inorganic and organic silts as tidal to shallow sub-tidal environments, possibly indicating co-seismic land-level changes. Gradual sea level fall after the deposition of the two paleotsunami sand deposits that changed the geomorphology of the coast and limited the accommodation space necessary to preserve additional overwash sediments could explain the 5000-year hiatus with no evidence of earthquakes or tsunamis. Further research will offer possible explanations for the exception of the 1960 tsunami in breaking this long-term pattern.


Identifying Key Factors Affecting Translational Landslides In Part Of The Yakima Fold And Thrust Belt, Washington State, Joseph Schilter Jan 2019

Identifying Key Factors Affecting Translational Landslides In Part Of The Yakima Fold And Thrust Belt, Washington State, Joseph Schilter

All Master's Theses

Washington has one of the fastest growth rates in the nation, and unfortunately also is among the most landslide-prone states. With increased population density and urban sprawl, the need for landslide hazard assessment grows. On the Columbia Plateau in central Washington, the smooth rigid, inclined surfaces of the Columbia River Basalts (CRBs) with loose sediment layers between them induces landslides of large blocks of bedrock. These hazards remain poorly understood, but their significance was heightened by the 2017 Rattlesnake Hills Landslide that currently threatens a community and an interstate highway south of Yakima, Washington. I propose that the strongest influences …


Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad Jan 2019

Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad

All Master's Theses

The causes and timing of cycles of aggradation and incision in the Hanson Creek drainage in central Washington provide insight into changes in channel morphology and paleoenvironment within the region over the last 8000 years. Stratigraphically and spatially coincident archaeological evidence reveals information related to human occupation during the latter half of the epoch. Using LiDAR imagery and field surveys, recent processes such as degree of modern channel incision, accumulation of valley floor sediment, channel morphology and gradient were evaluated. The spatial distribution of these channel characteristics was assessed in relation to proximal landforms such as colluvial deposits, basalt outcrops, …


Defining Historical Earthquake Rupture Parameters And Proposed Slip Distributions Through Tsunami Modeling In South-Central Chile, Alexander Dolcimascolo Jan 2019

Defining Historical Earthquake Rupture Parameters And Proposed Slip Distributions Through Tsunami Modeling In South-Central Chile, Alexander Dolcimascolo

All Master's Theses

Reliable tsunami early warning forecasts rely on accurate initial modeling conditions and interpretations of subduction zone behavior in a multi-century perspective. GPS and seismologic data were introduced this past century to study rupture dynamics in detail, however limited information is known about ruptures that pre-date the 20th century. I propose a methodology that uses statistics to better understand these pre-20th century ruptures. This methodology applies the historical and geologic tsunami record as a means to select a suite of tsunami simulations from earthquake source solutions. I chose south-central Chile (46°S to 30°S) to test this new methodology; it …


Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle Jan 2018

Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle

All Master's Theses

Low summer river base flow places a strain on natural and economic resources of the Eastern Cascades. A major contributor to stream flow in this region is snow pack which has declined over the past few decades because of a warming climate. In addition, glacial runoff, which contributes significantly to base flow in summer dry periods, will diminish from glacial recession. However, rock glaciers, because their internal ice (i.e., permafrost) is insulated by an outer debris layer, react slowly to climate change, thus acting as sinks for ice and liquid water storage in mountain environments. This study utilized ground penetrating …


Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver Jan 2018

Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver

All Master's Theses

Along the Columbia River, hundreds of miles of transportation infrastructure and over sixty hydroelectric dams have been constructed. This altered a rich cultural landscape with evidence of 10,000 years of continuous occupation. Researchers have attempted to understand the impacts of anthropogenic factors on the Columbia River, focusing on the riverine environment. However, the effect of transportation and hydroelectricity developments to eolian landforms on the floodplains and adjoining slopes have not been studied. Focusing on 2,800 acres near Celilo Falls, this study 1) establishes a baseline condition of eolian landforms from 1805 to 1900; 2) conducts an air photo increment analysis …


Spatial And Temporal Characterization Of The Petrified Springs Fault, Central Walker Lane, Nevada: Documenting Middle Miocene Dextral Slip, Andrew Hoxey Jan 2018

Spatial And Temporal Characterization Of The Petrified Springs Fault, Central Walker Lane, Nevada: Documenting Middle Miocene Dextral Slip, Andrew Hoxey

All Master's Theses

The Central Walker Lane, NV is an active dextral shear zone superimposed on the western boundary of the Basin and Range extensional province. Approximately 25% of dextral shear along the Pacific-North American plate boundary accommodated in the Walker Lane, a NW-striking, intracontinental dextral fault system in eastern California- western Nevada. In the Central Walker Lane, shear is accommodated on five major NW- striking faults, one of which is the Petrified Springs fault, with poorly constrained slip magnitudes, slip rates, and initiation ages. We completed new detailed geologic mapping, combined with structural studies, and 40Ar/39Ar geochronology document offset …


Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach Jan 2018

Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach

All Master's Theses

The nearly continuous volcanic eruption record at Mt. Etna dating back approximately 700 years provides an excellent opportunity to investigate the geochemical evolution of a highly active volcano. Of particular interest is elucidating the cause of a selective enrichment in alkali elements (K, Rb, Cs) and 87Sr/86Sr. This alkali enrichment trend, which began in the 17th century and accelerated after 1971, was accompanied by an increase in the volume, frequency, and explosivity of eruptions. To explain this enrichment, two major arguments are invoked: (1) crustal contributions (e.g., assimilation of the sedimentary basement), and (2) changes in …


Assessing The Use Of Tsunami Simulations As A Tool To Predict Source Magnitudes And Locations Of Paleoearthquakes In Chile, Rebeca Isabel Becerra Jan 2018

Assessing The Use Of Tsunami Simulations As A Tool To Predict Source Magnitudes And Locations Of Paleoearthquakes In Chile, Rebeca Isabel Becerra

All Master's Theses

A long-term goal of paleotsunami studies is the ability to predict paleoearthquake parameters based on tsunami deposits found on land. Chile provides an exemplary location for testing methods of making these predictions because the historical record includes 41 major earthquakes as far back as 1562 AD, and there are many known paleotsunami deposits throughout the region. Using these records as a comparison tool, I evaluated simulated tsunami wave heights and inundation extent with the tsunami model GeoClaw for nine hypothetical tsunamigenic large earthquakes (Mw 8.6, 8.8, and 9.0) in south-central Chile with epicenters at -35.1º, -38.8º, and -42.9º. As …