Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

PDF

2019

Earth Sciences

Institution
Keyword
Publication
Publication Type

Articles 1741 - 1759 of 1759

Full-Text Articles in Entire DC Network

Utilization Of Various Methods And A Landsat Ndvi/Google Earth Engine Product For Classifying Irrigated Land Cover, Andrew Nemecek Jan 2019

Utilization Of Various Methods And A Landsat Ndvi/Google Earth Engine Product For Classifying Irrigated Land Cover, Andrew Nemecek

Graduate Student Theses, Dissertations, & Professional Papers

Methods for classifying irrigated land cover are often complex and not quickly reproducible. Further, moderate resolution time-series datasets have been consistently utilized to produce irrigated land cover products over the past decade, and the body of irrigation classification literature contains no examples of subclassification of irrigated land cover by irrigation method. Creation of geospatial irrigated land cover products with higher resolution datasets could improve reliability, and subclassification of irrigation by method could provide better information for hydrologists and climatologists attempting to model the role of irrigation in the surface-ground water cycle and the water-energy balance. This study summarizes a simple, …


Quantifying The Magnitude And Spatial Variability Of Bedrock Erosion Beneath The Sisters Glacier, Washington, Using Cosmogenic 3he Concentrations, Sarah W. Francis Jan 2019

Quantifying The Magnitude And Spatial Variability Of Bedrock Erosion Beneath The Sisters Glacier, Washington, Using Cosmogenic 3he Concentrations, Sarah W. Francis

WWU Graduate School Collection

Cosmogenic 3He analyses provide a tool to infer spatial variation of cirque-glacial bedrock erosion. 3He accumulates in bedrock exposed at the surface as a result of cosmic ray bombardment; the concentration of cosmogenic 3He increases with exposure time as well as proximity to the surface. The Twin Sisters range, North Cascades, WA is an ideal location to use cosmogenic 3He to infer cirque-glacial erosion depths and rates, due to the dunite bedrock and the detailed record of Holocene glaciation from the nearby Mount Baker. We used field mapping, lidar data and aerial imagery to identify bedrock …


Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman Jan 2019

Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman

WWU Graduate School Collection

The Stillaguamish River in northwest Washington State, USA, provides water resources to local agriculture, industry and First Nations Tribes, and provides crucial habitat for several endangered species of salmonids. The watershed experiences a mild maritime climate and high relief, with rain and snowmelt dominating the streamflow. In anticipation of shifts in snowpack, streamflow, and stream temperature, I use projected global climate scenarios and numerical models to examine future climatic variability on streamflow and stream temperatures in the snow-melt dominated North Fork of the Stillaguamish River. I calibrated the physically based Distributed Hydrology Soil Vegetation Model (DHSVM) and River Basin Model …


Seismic Structure Of Tanaga Island, Alaska, Kevin F. (Kevin Francis) Lally Jan 2019

Seismic Structure Of Tanaga Island, Alaska, Kevin F. (Kevin Francis) Lally

WWU Graduate School Collection

Tanaga Island is located in the Central Aleutian Islands and includes four stratovolcanoes: Sajaka, Tanaga, and East Tanaga in the northwest, and Takawangha in the central part of the island. Of these volcanoes, only Tanaga has a record of historical eruptive activity (in 1914). Over 3,000 earthquakes have been recorded beneath the island and the surrounding offshore region since the six-station seismic network was emplaced in 2003. The origin of these earthquakes is not completely understood, and to arrive at this understanding, more accurate hypocenter locations and power spectra need to be determined. A better analyses including improved locations of …


Increased Hydrologic Variability Near The Paleocene-Eocene Boundary (Piceance Creek Basin, Colorado, U.S.A.)), Anna Lesko Jan 2019

Increased Hydrologic Variability Near The Paleocene-Eocene Boundary (Piceance Creek Basin, Colorado, U.S.A.)), Anna Lesko

WWU Graduate School Collection

The Paleocene Eocene Thermal Maximum (PETM) was a rapid global warming event that occurred approximately 56 million years ago and represents the largest and most abrupt warming event of the Cenozoic Era. The PETM caused mean annual temperatures to increase at least 5°C globally above the already warm, greenhouse climate state of the early Paleogene. The warming and associated perturbation of the carbon cycle had numerous consequences for paleoenvironments and paleobiologic systems. This study investigates the hydrologic response to the PETM within the interior of North America and presents a new d13C bulk organic record. This study generates …


Clinopyroxene Trace Element Chemistry As A Proxy For Magma Compositional Variations In The Izu Bonin Rear Arc Over The Last 15 Million Years, Kimberly N. (Kimberly Nicole) Wurth Jan 2019

Clinopyroxene Trace Element Chemistry As A Proxy For Magma Compositional Variations In The Izu Bonin Rear Arc Over The Last 15 Million Years, Kimberly N. (Kimberly Nicole) Wurth

WWU Graduate School Collection

This study presents major and trace element chemistry of clinopyroxene (CPX) in 0-15 Ma core material recovered from Site U1437 during IODP Expedition 350. Because no fresh glass is present in the core samples older than 4.4 Ma, and hence there is no way to directly determine magma compositions, my study presents the development of a novel method for calculating liquid compositions from CPX grains in volcaniclastic sediments using distribution coefficients and trace elements measured in CPX.

Geochemical data from CPX grains was acquired using a laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS). These data were used to calculate trace element …


Assessing Coastal Vulnerability To Storm Surge And Wave Impacts With Projected Sea Level Rise Within The Salish Sea, Nathan R. Vanarendonk Jan 2019

Assessing Coastal Vulnerability To Storm Surge And Wave Impacts With Projected Sea Level Rise Within The Salish Sea, Nathan R. Vanarendonk

WWU Graduate School Collection

Sea level rise (SLR) in the Salish Sea, a large inland waterway shared between Canada and the United States, is expected to be 0.3 to 1.8 m by the year 2100. Uncertainty in greenhouse gas emissions, global ice sheet loss, and other controls such as vertical land movement all contribute to this range. Valuable property, infrastructure, and critical habitats for shellfish and threatened salmon populations are at risk to coastal changes associated with SLR. Additionally, development in Washington State is expected to accelerate through the end of the 21st century adding extra pressure on protecting ecosystems and people from natural …


Validation Of Predicted Tsunami Inundation For The Inland Coast Of The Salish Sea Associated With Cascadia Subduction Zone Earthquakes, Paige Morkner Jan 2019

Validation Of Predicted Tsunami Inundation For The Inland Coast Of The Salish Sea Associated With Cascadia Subduction Zone Earthquakes, Paige Morkner

WWU Graduate School Collection

The Cascadia subduction zone is understood to produce large, Mw 9.0, earthquakes every 300-1000 years. As a result of large ruptures along the fault, Washington, Oregon and Northern California, are susceptible large tsunamis along the coast. Hazard modeling and mapping along the Cascadia subduction zone has concluded that large tsunamis are able to travel through the Strait of Juan de Fuca and inundate coastal regions of the Salish Sea and Puget Sound. However, to improve modeling efforts, field validation of models is required. Tsunamis can move material from the near shore and beach and deposit in low-laying coastal marshes and …


Paleomagnetic Results From Upper Triassic And Middle Jurassic Strata Of East-Central New Mexico, And Implication For North American Apwp, Masoud Mirzaei Souzani Jan 2019

Paleomagnetic Results From Upper Triassic And Middle Jurassic Strata Of East-Central New Mexico, And Implication For North American Apwp, Masoud Mirzaei Souzani

WWU Graduate School Collection

Two contradictory apparent polar wander paths (APWPs) of North America (NA) for most of Jurassic time have been the subject of many studies since the 1990s, and are important to rectify if in order to constrain the tectonic evolution of the continent. Among various efforts to resolve this persistent issue, additional results from well-dated kimberlite volcanics have been used to support a higher-latitude APWP (Kent et al., 2015), and the controversy was blamed on inclination error (IE) in paleomagnetic results of sedimentary units, most of which are from the U.S. South Western interior. Those paleomagnetic poles define the other, lower-latitude …


Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, Cody Duckworth Jan 2019

Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, Cody Duckworth

WWU Graduate School Collection

Upper-plate faulting in the Olympic Peninsula of Washington State reflects the interaction of crustal blocks within the Cascadia forearc as well as contributions from various earthquake cycle processes along the Cascadia subduction zone (CSZ). These processes include interseismic coupling, megathrust earthquakes, and aseismic slow slip events. In this study I utilize high resolution airborne lidar, field mapping of deformed surficial deposits and landforms, optically stimulated luminescence (OSL) dating and radiocarbon dating to reconstruct fault slip rates since Late Pleistocene deglaciation on the Sadie Creek fault (SCF), located north of the Olympic Mountains. This mapping reveals the SCF as a ~14 …


Photometric Investigations Of Weathering Rinds And Coatings With Implications For Mars, Kathleen Hoza Jan 2019

Photometric Investigations Of Weathering Rinds And Coatings With Implications For Mars, Kathleen Hoza

WWU Graduate School Collection

Reflectance spectroscopy is a major technique for characterizing the composition of planetary surfaces, and has led to many key findings in planetary geology. In laboratory measurements, reflectance spectrometers typically acquire data using a standard, fixed viewing geometry. Measurements from spacecraft, however, may be acquired at a wide range of viewing geometries, depending on the orientation of the instrument relative to the target surface and the Sun. For many materials, the impact of viewing geometry on reflectance is minor; however, some materials’ spectral signatures can be influenced by these photometric effects. In particular, spectra of weathering rinds and rock coatings are …


Beneath The Gypsum Dunes: Cenozoic History Of Wind And Water From A Core Drilled At White Sands, New Mexico, Jackson Bentley Jakeway Jan 2019

Beneath The Gypsum Dunes: Cenozoic History Of Wind And Water From A Core Drilled At White Sands, New Mexico, Jackson Bentley Jakeway

Graduate Theses, Dissertations, and Problem Reports

White Sands, New Mexico is the largest gypsum dune field on planet Earth, the result of reworking of gypsum deposits. The dunes have been well studied, but the Cenozoic history preceding the formation of the dune field has been poorly studied. A core drilled to a depth of 192 ft (58.5 m) beneath the modern dune field contains deposits from saline lakes, sandflats, perennial freshwater lakes, perennial brackish to saline lakes, and saline mudflats.

The core is composed of bottom-growth bedded gypsum, gypsum sandstone and siltstone, mixed siliciclastic-gypsum sandstones and siltstones, laminated siliciclastic mudstones, gypsum mudstones, and carbonate mudstones. Bottom-growth …


Petrophysical And Geomechanical Characterization Of The Marcellus Shale In The Appalachian Basin, Yixuan Zhu Jan 2019

Petrophysical And Geomechanical Characterization Of The Marcellus Shale In The Appalachian Basin, Yixuan Zhu

Graduate Theses, Dissertations, and Problem Reports

In recent years, more and more attention is paid to shale gas and hydrocarbon liquids exploration and exploitation in unconventional reservoirs. With the development of horizontal drilling and hydraulic fracturing, production from unconventional reservoirs has been greatly increased. However, not all wells, regions and basins harbor highly successful shale gas and liquids producers. In order to improve the production efficiency and reduce the cost of projects, detailed analysis needs to be undertaken to characterize the reservoir. As opposed to conventional reservoirs, extraction of gas in the unconventional reservoir is dependent not only on the reservoir quality, but also on completion …


A Machine-Aided Seismic Signal Analysis Workflow For Subsurface Faults And Facies Visualization And Interpretation, South Central Anadarko Basin, Oklahoma, Wade Martin Jan 2019

A Machine-Aided Seismic Signal Analysis Workflow For Subsurface Faults And Facies Visualization And Interpretation, South Central Anadarko Basin, Oklahoma, Wade Martin

Graduate Theses, Dissertations, and Problem Reports

Seismic attribute analysis enhances the understanding of subsurface geology and has continually gained traction in the oil and gas industry since the 1970’s. Many seismic attributes are available for petroleum geoscientists. This research intends to provide insight to an analytical attribute workflow for rock property estimation in the Anadarko basin of Oklahoma that is prolific in oil and gas exploration, with a particular focus on seismic texture. 3-D volumes processed for seismic texture facies and structure enhance geophysical investigation and interpretation of amplitude data. This study will contribute valuable insight to reservoir studies and the potential for texture attribute well …


Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson Jan 2019

Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson

Graduate Theses, Dissertations, and Problem Reports

The Arctic Alaska–Chukotka microplate is a large Mesozoic–Cenozoic composite terrane that resides at the northern limit of the North American Cordillera. Although its Mesozoic origins are assuredly linked to the opening of the Amerasian Basin of the Arctic Ocean, its Paleozoic origins can be linked to at least three separate paleocontinents, including northern Laurentia, Baltica, and Siberia. Across the Arctic Alaska portion of the microplate, an internal, mid-Paleozoic suture zone presumably separates rocks of the North Slope subterrane (Laurentian affinity) from a collection of smaller subterranes in the southern Brooks Range and Seward Peninsula (Baltic affinity).

The mountains of the …


Death-Defying Morphologies: Mass Extinction And Disparity In The Order Harpetida, James Desmond Beech Jan 2019

Death-Defying Morphologies: Mass Extinction And Disparity In The Order Harpetida, James Desmond Beech

Graduate Theses, Dissertations, and Problem Reports

The trilobite order Harpetida has long been easily recognized but poorly understood. This study seeks to better understand the phylogenetic relationships within Harpetida, with a view towards using this group to explore the relationship between extinction intensity and disparity. The harpetid response to the Late Ordovician mass extinction is of particular interest. A discrete morphological character matrix was created from the formal descriptions of harpetids in the published trilobite literature, and refined using first-hand observations of harpetid fossils. The final matrix consists of 76 discrete characters, including 69 cephalic characters, three thoracic characters, and four pygidial characters. This matrix is …


Correlation Between Mehlich-3 And Ammonium Acetate Extractable Potassium In Kansas Soils, B. Rutter, D. A. Ruiz Diaz Jan 2019

Correlation Between Mehlich-3 And Ammonium Acetate Extractable Potassium In Kansas Soils, B. Rutter, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

The K-State Research and Extension Soil Testing Laboratory has been using Mehlich-3 soil test procedures for phosphorus (P) extraction, and ammonium acetate extraction for potassium (K). Previous research in other states has shown a strong correlation between these two tests for K, but data correlating the two in Kansas soils have been limited. A study was performed on soils from across the state to investigate the relationship between these two methods. A strong positive correlation was observed (r = 0.99) across the wide range of soil types, pH, and fertility conditions represented in the sample set. Linear regression suggests a …


Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes Jan 2019

Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes

Graduate Theses, Dissertations, and Problem Reports

Eurypterids were a group of aquatic chelicerates that lived throughout most of the Paleozoic. While swimming eurypterids are generally considered to be active predators, the benthic stylonurine eurypterids appear to have had a mode of life similar to modern horseshoe crabs with the exception of two clades, the Stylonuroidea and the Mycteropoidea, both of which independently evolved modifications for sweep-feeding on their anterior appendages. Among extant suspension feeders, it has been shown that there is a linear correlation between the average spacing of feeding structures and prey sizes. This relationship was extrapolated to the sweep-feeding stylonuroid and mycteropoid eurypterids in …


Sediment Provenance Study Of The Lower Hamilton Group: An Analysis Of The Organic-Rich Facies And Its Depositional History, Luke Patrick Fritz Jan 2019

Sediment Provenance Study Of The Lower Hamilton Group: An Analysis Of The Organic-Rich Facies And Its Depositional History, Luke Patrick Fritz

Graduate Theses, Dissertations, and Problem Reports

Currently, insufficient geological models exist to explain the variability and distribution of TOC in the Marcellus Shale, within the Hamilton Group. TOC is one of the several limiting factors for natural gas production within the Marcellus Shale basin. One possible explanation for the low TOC regions is that detrital dilution was variable across the basin, with different sediment sources contributing detritus to low TOC areas, compared to surrounding regions with higher TOC. This hypothesis is tested by analyzing the source composition of inorganic detritus, using elemental and mineralogical proxies, with two cores in the Hamilton Group. The Armstrong #1 core …