Geomorphology Commons^™

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 …

Floodplain Aquifer Storage Capacity In Upper Yakima River Tributaries, Kittitas County, Wa, Emily Polizzi

All Master's Theses

Large wood (LW) restoration projects were recently implemented in the Upper Yakima Basin following the destructive logging practices of the early 20^th Century, which stripped Upper Yakima River tributaries of LW. The removal of natural LW increased incision, isolating channels from floodplain aquifers, and degrading resident and anadromous fish habitat. Returning streams to their natural state through instream LW installations is believed to increase floodplain groundwater storage by decreasing channel incision, increasing floodplain-channel connectivity, and raising the water table elevation. Additional storage in floodplain aquifers can help combat the adverse effects of climate change, namely decreasing snowpack and earlier …

Windblown Snow Bedforms And Their Effects On Snow Water Content Wenatchee Range, Washington, Ryan Hampton

All Master's Theses

ABSTRACT

WINDBLOWN SNOW BEDFORMS AND THEIR

EFFECTS ON SNOW WATER CONTENT

WENATCHEE RANGE, WASHINGTON

by

Ryan C. Hampton

June 2023

Windblown snow bedforms (WBSBF) are formations of distinct sizes, shapes, and patterns, resulting from the interaction of wind and snow particles. Due to the extreme nature of the formation of WBSBF, which occur in remote high elevation mountain environments during severe weather events, it makes it difficult to not only study these dramatic formations in real time but also predict their occurrence with any regularity. The purpose of this research was to 1) establish a method to actively monitor WBSBF …

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 …

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, …

Decadal-Scale Effects Of Large Wood Restoration On Channel Morphology And Groundwater Connectivity, Taneum Creek, Wa, Samuel Fixler

All Master's Theses

The importance of large wood (LW) in creating channel complexity is widely recognized; however, few LW projects have been in place long enough to track meaningful channel changes on a decadal timescale. Taneum Creek, located in central Washington, is one of the earliest LW restoration areas (2008) in the Yakima River Basin and the central Cascade Mountains. The flood in 2011, with an estimated discharge of 69 m³/s (2,400-2,800 cfs), provided further channel change by mobilizing LW and channel sediments. Three reaches with similar channel characteristics and LW additions were compared with a control reach without LW additions …

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 …

Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell Iii, Jason S. Padgett, Tina Dura, Simon E. Engelhart

Geological Sciences Faculty Scholarship

An understanding of the modern relationship between diatom species and elevation is a prerequisite for using fossil diatoms to reconstruct relative sea level (RSL). We described modern diatom distributions from seven transects covering unvegetated subtidal environments to forested uplands from four tidal wetland sites (Smith Creek, Bone River, Niawiakum River, and Naselle River) of Willapa Bay, Washington, USA. We compared our diatom dataset (320 species from 104 samples) to a series of environmental variables (elevation, grain-size, total organic carbon (TOC_SOM), and porewater salinity) using hierarchical clustering and ordination. While no single variable consistently explains variations in diatom assemblages …

Serial Interaction Of Primitive Magmas With Felsic And Mafic Crust Recorded By Gabbroic Dikes From The Antarctic Extension Of The Karoo Large Igneous Province, Jussi S. Heinonen, Arto V. Luttinen, Frank J. Spera, Saku K. Vuori, Wendy A. Bohrson

Geological Sciences Faculty Scholarship

Two subvertical gabbroic dikes with widths of ~ 350 m (East-Muren) and ≥ 500 m (West-Muren) crosscut continental flood basalts in the Antarctic extension of the ~ 180 Ma Karoo large igneous province (LIP) in Vestfjella, western Dronning Maud Land. The dikes exhibit unusual geochemical profiles; most significantly, initial (at 180 Ma) ε_Nd values increase from the dike interiors towards the hornfelsed wallrock basalts (from − 15.3 to − 7.8 in East-Muren and more gradually from − 9.0 to − 5.5 in West-Muren). In this study, we utilize models of partial melting and energy-constrained assimilation‒fractional crystallization in deciphering the …

Rock Glacier Hydrological Significance In A Warming World: A Geoecological Transect In The North Cascades, Washington, Jessica Abadie Coffey

All Master's Theses

Mountain environments are some of the most climate-sensitive areas on the planet. Due to recent warming trends, the 0℃ isotherm is rising in elevation and subsequently melting glaciers, snowpack, and permafrost. However, rock glaciers are a type of permafrost that is climate-resilient; therefore, research on their distribution and water volume equivalence (WVEQ) will be increasingly valuable in a warming world.

The purpose of this research was to determine the hydrological significance of different altitude belts of alpine permafrost in Washington State’s North Cascades. Additionally, this study analyzed how much rock glacier permafrost will be exposed to melting temperatures with climate …

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 …

Plate Boundary Trench Retreat And Dextral Shear Drive Intracontinental Fault-Slip Histories: Neogene Dextral Faulting Across The Gabbs Valley And Gillis Ranges, Central Walker Lane, Nevada, Jeffrey Lee, Andrew K. R. Hoxey, Andrew Calvert, Peter Dubyoski

All Faculty Scholarship for the College of the Sciences

The spatial-temporal evolution of intracontinental faults and the forces that drive their style, orientation, and timing are central to understanding tectonic processes. Intracontinental NW-striking dextral faults in the Gabbs Valley–Gillis Ranges (hereafter referred to as the GVGR), Nevada, define a structural domain known as the eastern Central Walker Lane located east of the western margin of the North American plate. To consider how changes in boundary type along the western margin of the North American plate influenced both the initiation and continued dextral fault slip to the present day in the GVGR, we combine our new detailed geologic mapping, structural …

Changing Mantle Sources And The Effects Of Crustal Passage On The Steens Basalt, Se Oregon: Chemical And Isotopic Constraints, Nicole E. Moore, A. L. Grunder, Wendy A. Bohrson, Richard W. Carlson, I. N. Bindeman

Geological Sciences Faculty Scholarship

Continental flood basalts are more prone to compositional modification from passage through thicker and (or) more felsic crust in comparison to their oceanic counterparts. The Steens Basalt in southeast Oregon (~17 Ma) is among the oldest and most mafic members of the Columbia River Basalt Group and provides a record of the early stages of flood basalt volcanism. We evaluate the balance of mantle sources in time during the onset of Columbia River Basalt Group magmatism and assess the effect of crustal passage using stratigraphically controlled Sr, Nd, Pb, Hf, Os, and O isotopic compositions, as well as whole rock …

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 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 …

The Role Of Cumulate Plagioclase Entrainment In The Steens Basalt, Se Oregon: Insights From The Magma Chamber Simulator, Valerie Strasser

All Master's Theses

The Steens Basalt, located in SE Oregon, is the oldest and most mafic member of the Columbia River Basalt Group (CRBG). Because the Steens Basalt contains large (up to 6 cm) and abundant (up to 40%) plagioclase crystals, it is classified as a Giant Plagioclase basalt (GPB). Understanding the origin of these giant plagioclase yields insight into magmatic processes like recharge, crustal assimilation, cumulate entrainment, and fractional crystallization. Because large and abundant plagioclase are found in other flood basalt provinces worldwide, these results could also enhance understanding of magma evolution and storage conditions for GPB worldwide. The Steens basalt is …

Distribution Of Invasive Plant Species On Debris Cones At Mount Rainier National Park, Shaun Morrison

All Master's Theses

Invasive plant populations within Mount Rainier National Park are a biological and ecological threat to the unique mountain landscape. A better understanding of their distribution and transport within the landscape is needed to improve invasive species monitoring for National Park Service management. This study investigates how invasive plant populations in Stevens Canyon are utilizing the debris cone disturbances and associated geomorphic processes to facilitate movement within the park. Vegetation transects were performed along Stevens Canyon Road (to observe the roadside community composition) and on the debris cone features (to observe species movement from the roadside). These vegetation observations are presented …

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

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

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, …

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

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 …

Abandoned Mine Land Impacts On Tributaries In The Upper Yakima River Watershed, Eastern Cascades, Washington, Scott Kugel

All Master's Theses

Effluent from abandoned mine lands (AMLs) in several drainages in Washington’s Eastern Cascades flows into the Yakima River. Similar sites in Idaho and Colorado are known producers of heavy metals and acid mine drainage. I determined the effects of nine AMLs on water quality in four tributaries to the Yakima River. Archival work was conducted to determine sites that were mined and contained a mill. Each site was characterized by physical features. Water and sediment samples were collected above, at, and below each AML. Samples were analyzed for pH and heavy metal content, and evaluated to determine if the AMLs …

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 (M_w 8.6, 8.8, and 9.0) in south-central Chile with epicenters at -35.1º, -38.8º, and -42.9º. As …

The Origin Of Dark Mats At The Sunrise Ridge Borrow Pit Site (45pi408) Mount Rainier National Park, Washington, Sean Stcherbinine

All Master's Theses

The Sunrise Ridge Borrow Pit Site is a precontact archaeological site located in the upland forest soils of Mount Rainier National Park. Site stratigraphy is complicated, consisting of tephra deposits from mostly known origins that are intercalated with dark sediments of unknown origin, referred to here as dark mats. Precontact occupation has been split previously into two components based on the ambiguous depositional history of the dark mats, notably their unknown parent material, depositional environment, and relationship with adjacent tephra strata. Stratigraphic samples from excavation units, features, and one off-site excavation unit was used to investigate these data gaps. Grain …

Quantifying Sedimentation Patterns Of Small Watersheds In The Central Oregon Coast Range Using Landslide-Dammed Lakes, Logan Wetherell

All Master's Theses

Up to 250 years of sedimentation patterns in headwater streams are preserved with detail in landslide-dammed lakes of the central Oregon Coast Range. I hypothesize that both anthropogenic and natural perturbations should increase linear and mass sediment accumulation rates and be discernible spatially and temporally in the sediment record with use of ¹³⁷Cs, high resolution charcoal stratigraphy, and aerial photography. Klickitat Lake and Wasson Lake are landslide-dammed lakes in small watersheds (<10 >km²) that contain drowned Douglas-fir stumps that are used for accurate dendrochronology and precise timing of the lake formation. An age-depth relationship was developed using …

The Uppermost Mantle Seismic Velocity And Viscosity Structure Of Central West Antarctica, J. P. O'Donnell, K. Selway, A. A. Nyblade, R. A. Brazier, D. A. Wiens, S. Anandakrishnan, R. C. Aster, Audrey D. Huerta, T. Wilson, J. Paul Winberry

All Faculty Scholarship for the College of the Sciences

Accurately monitoring and predicting the evolution of the West Antarctic Ice Sheet via secular changes in the Earth's gravity field requires knowledge of the underlying upper mantle viscosity structure. Published seismic models show the West Antarctic lithosphere to be ∼70–100 km thick and underlain by a low velocity zone extending to at least ∼200 km. Mantle viscosity is dependent on factors including temperature, grain size, the hydrogen content of olivine, the presence of partial melt and applied stress. As seismic wave propagation is particularly sensitive to thermal variations, seismic velocity provides a means of gauging mantle temperature. In 2012, a …

Origin Of Primitive Ocean Island Basalts By Crustal Gabbro Assimilation And Multiple Recharge Of Plume-Derived Melts, Anastassia Y. Borisova, Wendy A. Bohrson, Michel Grégoire

All Faculty Scholarship for the College of the Sciences

Chemical Geodynamics relies on a paradigm that the isotopic composition of ocean island basalt (OIB) represents equilibrium with its primary mantle sources. However, the discovery of huge isotopic heterogeneity within olivine‐hosted melt inclusions in primitive basalts from Kerguelen, Iceland, Hawaii and South Pacific Polynesia islands implies open‐system behavior of OIBs, where during magma residence and transport, basaltic melts are contaminated by surrounding lithosphere. To constrain the processes of crustal assimilation by OIBs, we employed the Magma Chamber Simulator (MCS), an energy‐constrained thermodynamic model of recharge, assimilation and fractional crystallization. For a case study of the 21–19 Ma basaltic series, the …

Unusual Geologic Evidence Of Coeval Seismic Shaking And Tsunamis Shows Variability In Earthquake Size And Recurrence In The Area Of The Giant 1960 Chile Earthquake, M. Cisternas, E. Garrett, R. Wesson, T. Dura, Lisa L. Ely

All Faculty Scholarship for the College of the Sciences

An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca-South American plate boundary. A 500-m long coastal outcrop on Isla Chiloé, midway along the 1960 rupture, provides continuous exposure of soil horizons buried locally by debris-flow diamicts and extensively by tsunami sand sheets. The diamicts flattened plants that yield geologically precise ages to correlate …

Data Potential Of Archaeological Deposits At The Chelan Station Site, Matthew J. Breidenthal

All Master's Theses

The Chelan Station Site (45CH782/783), located along the Rocky Reach of the Columbia River, includes lithic and faunal artifacts buried beneath volcanic tephra from Mt. Mazama (6,830 BP). Artifacts were inadvertently discovered in buried soils within a secondary alluvial terrace during construction of a pipeline to supply water to the Beebe Springs Fish Hatchery. This thesis stems from participation in original field work and includes the author’s own models of early land forms and site formation. The study reviews the construction monitoring and archaeological testing of both sites, and documents the archaeological data potential early occupations of the vicinity. The …