Geomorphology Commons^™

The Geomorphology And Hydrogeology Of Pre-Restoration West Fork Teanaway River, Wa, Usa, Shana M. Egan

All Master's Theses

The West Fork Teanaway (WFT) River in Kittitas County, WA is an entrenched bedrock river channel with disturbed floodplain geomorphology and degraded riparian ecology. Two stream restoration approaches, “stage 0” valley bottom reset and engineered logjam installation, will be installed at the WFT in summer 2026 by collaborators at the Washington State Department of Fish and Wildlife and Mid-Columbia Fisheries Enhancement Group. The objective of this study was to constrain the pre-restoration geomorphic and hydrologic conditions of the WFT. The WFT has an unconsolidated floodplain aquifer of predominantly coarse-grained fluvial deposits. Monitoring of groundwater and surface water levels began in …

Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis

All Master's Theses

Catastrophic flood events such as landslide tsunamis and jökulhlaups in glaciated areas can transport and strand icebergs, which obstruct the flow of floodwaters and leave a unique and recognizable grounded iceberg wake pattern in the sediment surface. Grounded iceberg wake patterns (GIWs) were identified at the two study areas in Southcentral Alaska; the outwash plain of a 1967 landslide tsunami at the Grewingk Glacier and proglacial lake, and the Matanuska River valley which experienced an unrecorded jökulhlaup in recent geological times. From these sites, 110 GIWs were identified through visual interpretation of lidar imagery and characterized by measuring their geometry, …

Using Simulated Cascadia Fakequakes To Interpret Paleotsunami Patterns, Anthony M. Joyce

All Master's Theses

This study uses GeoClaw to simulate 8 instantaneous rupture test earthquakes and 48 stochastic earthquakes (Fakequakes) along the Cascadia Subduction Zone to better understand tsunami generation and propagation. The primary goal is to evaluate how variations in Fakequake rupture patterns affect tsunami heights at coastal sites in the Pacific Northwest. The study focused on comparing inner and outer coast wave heights and impacts to understand how the Olympic Peninsula provides a barrier of protection to inner coast sites from southern-generated tsunamis, and implications for tsunami hazard at Naval Air Station Whidbey Island (NASWI).

Test earthquakes show increased amounts of slip …

The Use Of Lidar In The Study Of Terrain Ruggedness Of Tsunami Inudation Areas At Grewingk Lake And Taan Fiord, Alaska Usa, Shannon P. Mckinnion

All Master's Theses

ABSTRACT

THE USE OF LIDAR IN THE STUDY OF TERRAIN RUGGEDNESS OF TSUNAMI INUDATION AREAS AT GREWINGK LAKE AND TAAN FIORD, ALASKA USA

by

Shannon Patricia McKinnion

In order to test the hypothesis that lidar technologies can detect possible changes in terrain ruggedness due tsunami inundation within a designated area, digital elevation models (DEM) were generated from lidar data for two sites with known tsunami inundation— Grewingk Lake, Alaska and Taan Fiord, Alaska. Cobbles and boulders in these locations were examined using existing terrain ruggedness tools in ArcHydro— Terrain Ruggedness Index (TRI) and Vector Ruggedness Measurement (VRM). The average values …

A Comparison Of Sediment Accumulation Effectiveness Behind Beaver Dam Analogues, One Rock Dams, And Post-Assisted Log Structures On East Foster Creek, Douglas County, Wa, Griffin Hansen

All Master's Theses

Waterways are valuable resources for communities and habitats, but are subject to degradation in the form of incision. This is a type of streambed erosion where streams narrow and deepen. Sediment control dams were placed on East Foster Creek in Douglas County, WA to control incision following the 2020 Pearl Hill fire. This study examined sediment capture in the ponds behind these dams, which included beaver dam analogues (BDAs), one rock dams (ORDs), and post-assisted log structures (PALS). Sediment capture may be influenced by several factors, including dam type, height, width, distance between dams, vegetation, land use, topography, soil type, …

The Effects Of Environmental Factors On Tsunami Propagation And Inundation: A Comparison Of Earth With Other Planetary Bodies, Austin Halstead

All Master's Theses

Tsunamis are a universal hazard in any environment with oceans or lakes. Having a firm understanding of them is essential because of this. However, the vast number of tsunami studies have been solely on Earth, despite the growing evidence of oceans and lakes being on, or having once existed on, other planets and moons. In this study, I investigated tsunami behavior in non-Earth environments by testing the effects of varying viscosity and gravity. I conducted simulations using GeoClaw, Flow3D®, and VolcFlow on established tsunami benchmarks to identify consistent patterns in tsunami flow patterns and inundation. The results show …

River Response To Removal Of A Small Dam And Replacement With A Roughened Channel, Chandler Sabin

All Master's Theses

Relatively few studies have analyzed how the removal of small dams and re-engineering of the channel affect river channel processes. The low-head Nelson Dam was built in 1920 on the Naches River in central Washington, causing two miles of aggraded sediments. This resulted in upstream flooding and excessive downstream incision that led to ineffective irrigation diversions, and hindered fish spawning. Nelson Dam was removed in 2021 and replaced with a graded, roughened, nature-like channel and a newly engineered diversion that was completed in 2023. The research presented here quantifies the effects of the Nelson Dam removal and channel redesign on …

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 …

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 …

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 …

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, …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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.

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, …

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 …

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 …

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 …