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2019

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The Role Of Small Reservoirs In Reducing Reactive N Export Via Denitrification, Margaret Phillips, Wil Wollheim Jan 2019

The Role Of Small Reservoirs In Reducing Reactive N Export Via Denitrification, Margaret Phillips, Wil Wollheim

Honors Theses and Capstones

Reactive nitrogen (N), which harms ecosystem health, has been increasing in the biosphere, leading to higher N export to coastal ecosystems. Although man-made reservoirs can be significant sources of greenhouse gases, they can also retain N, thus reducing N export. Because many dams are relics from industrial hydropower, their removal is becoming increasingly common. It is therefore crucial to understand the ecological tradeoffs of man-made reservoirs. While previous studies have examined nutrient budgets and denitrification at inputs and outputs of large reservoirs, small reservoir dynamics remain understudied. In this study, we measured inputs and outputs of NO3 and N …


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 …


Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath Jan 2019

Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Abstract: Phosgene in the atmosphere is produced via the degradation of carbon tetrachloride, methyl chloroform, and a number of chlorine‐containing very short lived substances (VSLS). These VSLS are not regulated by the Montreal Protocol even though they contribute to stratospheric ozone depletion. While observations of VSLS can quantify direct stratospheric source gas injection, observations of phosgene in the upper troposphere/lower stratosphere can be used as a marker of product gas injection of chlorine‐containing VSLS. In this work we report upper troposphere/lower stratosphere measurements of phosgene made by the ACE‐FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) instrument and compare with results …


Formation Of Water-Soluble Organic Matter Through Fungal Degradation Of Lignin, Seyyedhadi Khatami, Ying Deng, Ming Tien, Patrick G. Hatcher Jan 2019

Formation Of Water-Soluble Organic Matter Through Fungal Degradation Of Lignin, Seyyedhadi Khatami, Ying Deng, Ming Tien, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Lignin is a major component of decaying terrestrial vegetation in soils and has been reported to contribute substantially to the formation of soil carbon humus and associated water extracts of soil. To better understand this process of humification, lignin from brown-rot degraded wood is subjected to a white-rot fungus (Phanerochaete chrysosporium)whose enzymes are particularly effective in lignin degradation. This enzymatic attack was monitored by ultrahigh resolution mass spectrometry of water soluble extracts of the fungal cultures. The ensuing molecular level characterizations showed that the P. chrysosporium fungi induced aromatic ring oxidations followed by ring opening as expected. However, …


Bridge Deck Deterioration Assessment By Nondestructive Testing Methods, Thanop Siriwattananuruk Jan 2019

Bridge Deck Deterioration Assessment By Nondestructive Testing Methods, Thanop Siriwattananuruk

Chulalongkorn University Theses and Dissertations (Chula ETD)

In general, the inspection of the damage on concrete bridge deck is usually done by visual inspection and coring test together with simple survey such as chain drag and hammer sounding. These methods may not be able to verify damage condition correctly. However, at present, there are many nondestructive testing methods which is used to investigate the damage on concrete bridge deck together with simple testing methods. For this study, ground penetrating radar, half-cell potential and impact echo test were selected to evaluate damage condition of concrete bridge deck. The results from simple methods can be detect only damage on …


Geological And Mineralogical Characteristics Of Pilok And Takua Pit Thong Tin-Tungsten Deposits, Western Thailand, Karn Phountong Jan 2019

Geological And Mineralogical Characteristics Of Pilok And Takua Pit Thong Tin-Tungsten Deposits, Western Thailand, Karn Phountong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pilok and Takua Pit Thong mine were one of tin-tungsten mines associated with the Western Granitoid Belt. Despite the very poor condition of the outcrop, petrographic and geochemical studies reveal two granitoid units: porphyritic granite and equigranular granite, which show similar petrography characteristics except for tourmaline that appears only in equigranular granite, and their textures. Based on whole-rock geochemistry, porphyritic granite is ferroan to magnesian, alkalic, peraluminous granite whereas equigranular granite is ferroan to magnesian, alkali to alkali-calcic, peraluminous granite. Both granites show S-type affinity. The REE patterns show enrichment in LILE (e.g. K, Rb) and HFSE (e.g. Nb, Ta). …


Petrography And Geochemistry Of Volcanic Rocks In Khao Sam Sip Area, Sa Kaeo Province, Maythira Sriwichai Jan 2019

Petrography And Geochemistry Of Volcanic Rocks In Khao Sam Sip Area, Sa Kaeo Province, Maythira Sriwichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

The volcanic rocks at Khao Sam Sip, Sa Kaeo province is part of the Loei-Phetchabun-Sa Kaeo Volcanic Belt. Based on field observation, petrographic and geochemical studies, the rocks in the study area can be divided into four rock units namely, 1) Basalt-andesite unit, 2) Polymictic andesitic unit, 3) Epiclastic unit, and 4) Clastic unit. Unit 1 is the lowest unit in sequence consisting of olivine-pyroxene-plagioclase basalt, pyroxene basalt, hornblende-plagioclase andesite, and plagioclase andesite. Unit 2 consists of polymictic andesitic breccia and polymictic andesitic sandstone. Unit 3 is epiclastic unit comprising of crystal-lithic sandstone and polymictic conglomerate. Units 4 includes fine-grained …


Geology And Mineralization Characteristics Of Epithermal Gold, Suwan Prospect, Changwat Phitsanulok, Tanad Soisa Jan 2019

Geology And Mineralization Characteristics Of Epithermal Gold, Suwan Prospect, Changwat Phitsanulok, Tanad Soisa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Suwan prospect is located about 6 km northwest of the Chatree gold mine in Phitsanulok province, central Thailand. Gold-silver mineralization occurs as veins and stockworks hosted in volcaniclastic and volcanogenic-sedimentary rocks of Late Permian- Early Triassic age which is classified as a low sulfidation epithermal deposit base on mineralization texture, alteration pattern and sulfide mineral assemblages. From top to bottom, the hosted volcanic succession can be divided into 3 units, namely 1) Felsic volcanic unit (Unit 1), 2) Volcanogenic-sedimentary unit (Unit 2), and 3) Porphyritic andesite unit (Unit 3). Unit 1 consists predominantly of quartz-rich fiamme breccia, lithic-rich fiamme …


Terrain Analysis In Phetchabun Province, Tanapat Pichetsopon Jan 2019

Terrain Analysis In Phetchabun Province, Tanapat Pichetsopon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phetchabun province, lower northern Thailand is vulnerable to geohazards, landslide and flooding with the potential for significant harm to people and property. In addition, Phetchabun province has many lineaments that could be potential source of tectonic activities. In this study, terrain analysis techniques are used through 30 meters resolution Digital Elevation Model (DEM) data in order to determine geomorphic indices related to tectonic activity. The statistic index method (Si) is calculated in relation of six parameters to indicate landslide susceptible area. and the hydromorphometric contrast index (HCI) is used to identify sensitive area to flooding by evaluating five parameters. According …


Color Enhancement Of Tourmaline By Electron Beam Irradiation, Waratchanok Suwanmanee Jan 2019

Color Enhancement Of Tourmaline By Electron Beam Irradiation, Waratchanok Suwanmanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tourmaline is a semi-precious stone that is quite popular in gem market. Red-purple tourmaline, so-called “Rubellite”, is particularly famous. Consequently, pink tourmalines have recently been enhanced by gamma radiation to intensify color as rubellite. In this study, an electron beam technique was applied for experimental treatment. Moreover, gamma ray irradiation was also applied to treat the same sample collection for comparison. Color enhancement was designed for both radiations at three levels of doses, i.e., 400, 800, and 1,200 kilogreys. Pink and green tourmalines from Nigeria were collected for the experiment. Each sample was cut into two tablets for experimental irradiations …


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 …


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 …


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 …


Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot Jan 2019

Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot

Graduate Theses, Dissertations, and Problem Reports

The rugged, densely forested terrain of the West Virginia Appalachian Valley and Ridge Province has made it difficult for field-based studies to agree on the structure of the highly deformed Silurian-Devonian cover strata. In this study, we demonstrate a 3D approach to geologic mapping utilizing the structural information revealed in a “bare-earth” 1-m Lidar DEM of the Smoke Hole Canyon. The completed 3D map was integrated with kinematic forward modeling carried out in MOVETM to provide information on the parameters required to form the major structures observed. Additionally, land surface attributes generated using geomorphometric analysis of the Lidar allowed …


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 …


Automatic Detection And Analysis Of Rip Currents At Haeundae Beach Using X-Band Marine Radar, Chanyeong Oh, Kyungmo Ahn, Se-Hyeon Cheon Jan 2019

Automatic Detection And Analysis Of Rip Currents At Haeundae Beach Using X-Band Marine Radar, Chanyeong Oh, Kyungmo Ahn, Se-Hyeon Cheon

OES Faculty Publications

The observation system has been developed to investigate the rip currents at Haeundae beach using Xband marine radar. X-band radar system can observe shape, size, and velocity of rip currents, which is difficult to obtain through field observation by conventional device. Algorithms which automatically detect locations, shapes, and magnitudes of rip currents were developed using time averaged X-band radar sea clutter images. X-band sea clutter images are transformed through 3D FFT into 2D wave number spectrum and frequency spectrum. Rip current velocities were estimated using differences in wave-number spectra and wave frequency spectra due to Doppler shift. The algorithm was …


Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi Jan 2019

Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi

Graduate Theses, Dissertations, and Problem Reports

The deep subsurface environment has been known to host microbes as early as 1926 and has also been suggested to potentially account for as much as 50% of the Earth`s biomass. Researchers have shown that microbes alter their membrane lipid components in response to physiological stress, producing stress indicative lipid biomarkers. However, little effort has been made to understand the subsurface microbial community of the shale ecosystem which is increasingly being exploited and altered by addition of drilling and hydraulic fluids to meet our growing energy needs. Phospholipid fatty acids (PLFAs) are microbial lipid biomarkers and are found in all …


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 …


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 …


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 …


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 …