Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Geology (13)
- Paleomagnetism (13)
- Petrology (9)
- Climate change (8)
- Net shore-drift (8)
-
- Stratigraphy (7)
- Hemophilia A (6)
- Mount Baker (6)
- Sortase (6)
- Chuckanut Formation (5)
- Climate Change (5)
- Hydrology (5)
- Mars (5)
- Restoration (5)
- Salish Sea (5)
- Biochemistry (4)
- Blood Coagulation Factor VIII (FVIII) (4)
- Eelgrass (4)
- Geochronology (4)
- Glacier (4)
- North Cascades (4)
- Sediment transport (4)
- Sedimentology (4)
- Spectroscopy (4)
- Structure (4)
- Volcanology (4)
- X-ray Crystallography (4)
- Bayesian network (3)
- Benzoxazine (3)
- Climate (3)
- Publication Year
Articles 1 - 30 of 563
Full-Text Articles in Physical Sciences and Mathematics
Using Olivine-Hosted Melt Inclusions To Better Understand The Transcrustal Architecture Beneath Mount Baker (Koma Kulshan), North Cascades, Washington, Amanda Florea
WWU Graduate School Collection
The Schriebers Meadow cinder cone is located on the southern flank of Mount Baker and produced the Sulphur Creek lava flows and SC tephra deposits ~9.8 ka. Mount Baker, a Cascade volcano, is located ~50 km east of Bellingham, Washington. Previous work on the Sulphur Creek lava flows show that the eruption comprised two primary bulk rock compositions, ranging from basalt at the toe to basaltic andesite closer to the vent. However, little is known about the relative composition and eruption timing of the SC tephra from the same vent. In this thesis, I quantify compositional variations through the explosive …
Life Cycle Assessment Of A Hemp-Based Thermal Insulation Panel, Kara Davis
Life Cycle Assessment Of A Hemp-Based Thermal Insulation Panel, Kara Davis
WWU Graduate School Collection
Buildings have a monumental impact on the environment and the economy and account for about 40% of energy consumption, greenhouse gas emissions, and materials entering the economy. Life cycle assessment (LCA) is a tool for quantitatively evaluating the environmental impacts of a product throughout its life span commonly applied in the building and construction sector. While past efforts have focused on reducing operational energy and carbon, attention has shifted towards embodied energy and carbon as buildings become more energy efficient. This graduate thesis applies the LCA framework and investigates the life cycle environmental impacts of a hemp-based thermal insulation panel …
Biodiversity Of Snow Algae In The North Cascades: Comparing Distinct Microhabitats At Mount Watson., Chloe Beck
Biodiversity Of Snow Algae In The North Cascades: Comparing Distinct Microhabitats At Mount Watson., Chloe Beck
WWU Graduate School Collection
Snow algae, commonly known as pink snow, bloom in high alpine environments globally. Snow algae blooms are on every continent, but the biodiversity within them is under studied. The snow habitat is suitable for algae growth in the spring and summer months when liquid water is available in snowpacks. Diverse terrain in alpine systems can create unique and variable snow habitats as snow melts through the growing season. This study describes the biodiversity of blooms from a site, Mt. Watson, in the North Cascade Mountain Range. The measures of biodiversity assessed include species richness, alpha diversity, beta diversity, and genetic …
An Assessment Of Historical And Future Bluff Recession In Puget Sound, Wa, Callie Little
An Assessment Of Historical And Future Bluff Recession In Puget Sound, Wa, Callie Little
WWU Graduate School Collection
Sea level rise in the coming century is projected to cause substantial changes along the world’s coastlines and adverse effects to communities and environments. Among these changes, questions about the extent, rate, and uncertainty of coastal bluff retreat relative to historical observations and in response to sea level rise are critical to evaluate. Coastal bluffs comprise ~43% of the shoreline across Puget Sound in the Salish Sea and their recession is a growing concern to human safety, property, infrastructure, and diverse ecosystem services for culturally and commercially important fisheries. This project assesses bluff erosion using field observations, structure from motion …
The Biophysical Resilience Capacity Of The Salish Sea’S Tidal Wetlands To Sea Level Rise, Kenna Kuhn
The Biophysical Resilience Capacity Of The Salish Sea’S Tidal Wetlands To Sea Level Rise, Kenna Kuhn
WWU Graduate School Collection
Tidal wetlands offer significant ecosystem services, cultural identity, and economic opportunities, but the impact that projected SLR will have on tidal wetlands in the Salish Sea is not known. In this thesis, I examine the exposure, watershed-scale biophysical resilience capacity, and jurisdictional variation in resilience capacity of the Salish Sea’s tidal wetlands to SLR. I quantify exposure, resilience, and jurisdictional variation using existing spatial data and analysis techniques. I employ a framework for biophysical resilience capacity developed by NOAA and NERRA. This study’s results indicate that there is substantial variation in wetlands area by watershed, from 0 km2 to …
Deglacial And Holocene Environmental Change Recorded In Lake Sediments From The Snowy Mountains, Kosciuszko National Park, Southeastern Australia, Emma J. Mickelson
Deglacial And Holocene Environmental Change Recorded In Lake Sediments From The Snowy Mountains, Kosciuszko National Park, Southeastern Australia, Emma J. Mickelson
WWU Graduate School Collection
The sediment record from Lake Albina, the Snowy Mountains, southeastern Australia suggests significant environmental change mostly reflecting shifts in climate from the LGM through the Holocene. Immediately following deglaciation, approximately 19.4 thousand cal ky BP, Lake Albina experienced cold and/or dry conditions with minimal vegetation in the catchment. Cooler conditions persisted with a slight increase in moisture throughout the Antarctic Cold Reversal (ACR; 14.7-13 cal ky BP) aligning closest with a strengthening of the Atlantic Meridional overturning circulation (AMOC) and a northward shift of the South Westerly Winds (SWW). Between 12.9-9.7 cal ky BP, Lake Albina recorded a climate reversal …
Enhancing The Federal Natural Resource Damage Assessment And Restoration Process Through Bayesian Networks: A Case-Study On The Little Mississinewa River, Indiana, April D. Reed
WWU Graduate School Collection
The Federal Natural Resource Damage Assessment and Restoration (NRDAR) program gives Tribes and certain government agencies the authority to assess injury to natural resources and to pursue and implement compensatory action for any resources lost or injured due to unlawful releases of chemicals into the environment. This study was centered around the development of a Bayesian network (BN) decision support tool tailored to the needs of NRDAR practitioners. The goal was to design a probabilistic BN tool that could lend quantitative insight into natural resource injury. A case study was used to develop and demonstrate the tool’s functionality and propriety …
Revealing Binding And Unbinding Pathways Of Small Molecules And Peptides To Enzymes With Enhanced Sampling Methods, Kayla Ariana Croney
Revealing Binding And Unbinding Pathways Of Small Molecules And Peptides To Enzymes With Enhanced Sampling Methods, Kayla Ariana Croney
WWU Graduate School Collection
In vitro experiments are critical to understanding the biochemistry of molecular systems but it can be a challenge to obtain atomistic resolution. Computational chemistry gives insight to these results with molecular dynamics (MD) simulations using Newton’s equations of motion to analyze the motion of atoms and molecules. However, due to insufficient sampling and long-lived metastable states separated by high energy intermediates, enhanced sampling methods must be applied. Metadynamics (MetaD) enhances the exploration of MD by adding time-dependent bias. Here, we applied MetaD to two enzymes to study their substrate binding/unbinding pathways with their respective substrates. Yeast cytosine deaminase (yCD) deaminates …
Post Polymerization Modification And Preparation Of Dynamic Polymer Networks Via Guanylation Of Aryl Carbodiimides, Conner J. Klingler
Post Polymerization Modification And Preparation Of Dynamic Polymer Networks Via Guanylation Of Aryl Carbodiimides, Conner J. Klingler
WWU Graduate School Collection
Styrenic carbodiimide (CDI) polymers have shown an interesting ability to form reversible polymer networks, known as covalent adaptable networks (CANs), through an uncatalyzed reaction with multifunctional amines. CANs have been a topic of interest in polymer chemistry due to their ability to be reprocessed, which is not found in classic thermoset polymer networks. However, not much is known about the capabilities of the nucleophilic addition of amines to aryl CDI repeat unit structures that goes into making these networks due to the understudied reactions involved. This thesis aims to develop a better understanding of the chemistry involved through various post …
Transition State Kinetics Through Kramers’ Rate For Variationally Enhanced Sampling., David Cummins
Transition State Kinetics Through Kramers’ Rate For Variationally Enhanced Sampling., David Cummins
WWU Graduate School Collection
Molecular Dynamics (MD) simulations use Newtonian mechanics applied at finite time steps to numerically propagate the time-trajectory of a dynamical system. However, many biochemical processes such as catalysis, ion channel gating, substrate binding, and protein folding evolve over time scales which are orders of magnitudes greater than those afforded by MD and the computational power available today. The development of methods that reduce the computational cost of sampling such rare events help to provide a dynamic insight into these processes. This thesis explores the application of a recently developed enhanced sampling method, Variationally Enhanced Sampling (VES), for calculating kinetic rate …
High Resolution Seafloor Structure Of The Gofar Oceanic Transform Fault, Paige Koenig
High Resolution Seafloor Structure Of The Gofar Oceanic Transform Fault, Paige Koenig
WWU Graduate School Collection
The Gofar oceanic transform fault (OTF) accommodates 12.5 cm/year of plate boundary motion through large earthquakes, microseismic swarms, and aseismic slip in distinct regions of the fault along strike. Local and teleseismic observations show that well- coupled segments of the fault tend to fail via M~6 earthquakes roughly every 5 years. These fully-coupled segments are bound by barrier zones, up to ~10 km-wide, that do not generate large-magnitude earthquakes, but instead host microseismic swarms, accompanied by aseismic slip (Shi et al., 2021). Geophysical modeling and observations provide evidence that hydrothermal fluid circulation and fault damage may influence slip behavior segmentation. …
Does Sediment Supply Impact The Threshold For Initial Sediment Motion In Natural, Gravel Bedded Streams?, Emily Loucks
Does Sediment Supply Impact The Threshold For Initial Sediment Motion In Natural, Gravel Bedded Streams?, Emily Loucks
WWU Graduate School Collection
Sediment transport in river channels control channel morphology, streamflow, and benthic ecosystems. Predicting sediment transport rates through a channel is required for sediment management for stream restoration and aquatic habitat assessment. The critical Shields stress (τ*c), is a dimensionless parameter used in sediment transport models that characterizes the river bed surface shear stress required to initiate sediment motion. The τ*c is typically assumed constant in transport models, yet compilations of field data have shown that τ*c can vary wildly, causing sediment transport models to over- or under-predict fluxes by an order of magnitude or more. Understanding …
The Economic And Emissions Reduction Potential Of Air Source Heat Pumps As A Replacement For Natural Gas And Electric Resistance Space Heating In The Contiguous United States, Joshua Schraer
WWU Graduate School Collection
It is widely believed that to reduce CO2 emissions the best strategy is to electrify everything, decarbonize the grid, and improve energy efficiency. This research looks specifically at the use of air source heat pumps (AHP) as a tool to reduce the CO2 emissions of heating energy in the residential sector. The landscape of residential energy use is complicated by a broad range of factors. We compare AHP, natural gas (NG), and electric resistance (ER) heating using data from energy prices, temperature, appliance efficiency, building efficiency and marginal emissions data from 2019 as well as modeled data of …
Paleomagnetic Determination Of Vertical Axis Block Rotation Near The Doty Fault In Southwestern Washington, Charles Linneman
Paleomagnetic Determination Of Vertical Axis Block Rotation Near The Doty Fault In Southwestern Washington, Charles Linneman
WWU Graduate School Collection
In this paper I present the results of paleomagnetically derived vertical axis rotations (VARs) of sites in two different flows of the Columbia River Basalt (CRB) – the 16 Ma Sentinel Bluffs member of the Grande Ronde flow and the 12 Ma Pomona Member of the Packsack Lookout – near the Doty fault in southwestern Washington. In two field seasons, I collected 99 cores from 14 sites, 11 in the Grande Ronde flow and three in the Pomona member flow. Of the 227 specimens that I demagnetized, 212 had well-defined magnetic directions. Positive fold and reversal tests results confirm the …
Impact Of Riverbank Lupine (Lupinus Rivularis) On Grand Fir (Abies Grandis) Ectomycorrhizal Symbioses, Andrew Labay
Impact Of Riverbank Lupine (Lupinus Rivularis) On Grand Fir (Abies Grandis) Ectomycorrhizal Symbioses, Andrew Labay
WWU Graduate School Collection
Lupine (Lupinus rivularis) is used in the revegetation of coarse sediments surrounding the Elwha basin in Washington State due to its ability to improve soil conditions. Previous research illustrated that seeding lupine with conifers increased growth and foliar nitrogen, however, decreased ectomycorrhizal (ECM) root colonization, an important symbiosis for conifers used in restoration. We hypothesized the observed decrease in ECM may be due to lupine increasing soil nitrogen, negating the need for a fungal symbiont. To investigate this, we explored the interaction between lupine and ECM colonization of grand fir (Abies grandis) in both a field …
Glacial Loss And Threatened Fish: The Future Of Mount Rainier’S Cold-Water Bull Trout Habitats, Kathleen C. Ewen
Glacial Loss And Threatened Fish: The Future Of Mount Rainier’S Cold-Water Bull Trout Habitats, Kathleen C. Ewen
WWU Graduate School Collection
Glaciers play a key ecological role in the river systems that they support. Cold-water reaches supplied by glacial ice serve as critical habitats for aquatic organisms that rely on specific thermal ranges to survive. Federally threatened Bull Trout (Salvelinus confluentus) require very cold temperatures, like those found in glacial systems, to complete their life cycles. However, glaciers are retreating due to climate change and are expected to continue diminishing throughout this century. Decreased glacial extent could result in warmer stream temperatures downstream from glaciers and, depending on the magnitude of stream temperature increase, cold-water habitats relied upon by Bull Trout …
Coupling Unoccupied Aerial System Surveys And Elevation Measurements To Predict Native And Nonnative Eelgrass Cover In Padilla Bay, Jacqui Bergner
Coupling Unoccupied Aerial System Surveys And Elevation Measurements To Predict Native And Nonnative Eelgrass Cover In Padilla Bay, Jacqui Bergner
WWU Graduate School Collection
There are two primary species of eelgrass at the Padilla Bay National Estuarine Research Reserve, Zostera marina, a native eelgrass, and Zostera japonica, a nonnative. Unoccupied Aerial Systems (UAS) have been frequently used for eelgrass monitoring and mapping, especially for large populations like those in Padilla Bay. UAS imagery have resolutions of 10 cm or better and are much more cost and time effective than aerial surveys via traditional aircraft that may provide similar image resolutions. In this project, multispectral UAS imagery was coupled with a centimeter level Digital Elevation Model (DEM), created from Real Time Kinematic GNSS …
Learning From Traditional Ecological Knowledge: Paralytic Shellfish Toxins In Butter Clams, Jackelyn Garcia
Learning From Traditional Ecological Knowledge: Paralytic Shellfish Toxins In Butter Clams, Jackelyn Garcia
WWU Graduate School Collection
Anthropogenic forcing of marine ecosystems is disproportionately impacting Indigenous food systems and the health of coastal Indigenous communities. With increasing harmful algal events, there is rising concern for access and health of coastal communities who rely on shellfish for commercial, food, subsistence, and ceremonial harvest. In the U.S West Coast, the dinoflagellate Alexandrium spp. may produce paralytic shellfish toxins, which can cause shellfish to become toxic and is of especial concern. While recent research has led to greater awareness of the risks associated with paralytic shellfish toxins (PSTs), the concern for harmful algae is not new. Coastal Indigenous communities have …
Stereoselective Synthesis Of (+)- And (-)-Cananodine, Haley Holliday
Stereoselective Synthesis Of (+)- And (-)-Cananodine, Haley Holliday
WWU Graduate School Collection
Natural products are an important class of molecules utilized in traditional medicine and inspire drug design in medicinal chemistry. Cananga odorata, a tree commonly known as ylang-ylang, contains natural products known to positively benefit health, and specifically promote liver health. One alkaloid isolated from Cananga odorata, cananodine, possesses cytotoxic properties, specifically against hepatocellular carcinoma (HCC). HCC is the most common type of liver cancer, with one million diagnoses projected by 2025 globally. Cananodine is a member of the guaipyridine alkaloid family, a class of compounds that feature a substituted pyridine bonded to a seven-membered ring. The first enantiomer …
Structural, Mutational, And Kinetic Characterization Of Ura4, An Isocytosine Deaminase, Ashlee Hoffman
Structural, Mutational, And Kinetic Characterization Of Ura4, An Isocytosine Deaminase, Ashlee Hoffman
WWU Graduate School Collection
Cytosine Deaminases (CD) are a class of enzymes found in prokaryotes and fungi that have been studied in the past due to their ability to deaminate the prodrug 5-fluorocytosine (5-FC) producing 5-fluorouracil (5-FU). 5-FU is a common anti-cancer drug that can inhibit DNA synthesis leading to cancer cell death. 5-fluorocytosine can interact with digestive bacteria leading to unwanted side effects for cancer patients. Isocytosine Deaminases (ICD) are enzymes that are of interest in the treatment of cancers using Gene Directed Enzyme Prodrug Therapy (GDEPT). ICDs can deaminate the prodrug 5-fluoroisocytosine (5-FIC) also producing the drug 5-FU. 5-FIC will likely not …
Selectivity And Structure Of Chimeric Loop Swaps In Sh2 Domains, Sarah N. Smith
Selectivity And Structure Of Chimeric Loop Swaps In Sh2 Domains, Sarah N. Smith
WWU Graduate School Collection
SH2 (Src Homology 2) domains are protein domains that bind to phosphorylated tyrosine residues within cell signaling cascades. They have been found to play a role in certain cancers and immunological disorders. Despite their importance in cell signaling and medical relevance, the structural basis of the various selectivity classes of SH2 domains is only partially understood. Previous research found that the EF and BG loops of the domains contribute to forming the peptide binding pocket, and thus impact their selectivity. To further understand the role of these loops in selectivity, we engineered chimeric SH2 domains by swapping the EF and …
Regio- And Diastereoselective Samarium-Mediated Allylic Sulfone Reductions, Cody Schwans
Regio- And Diastereoselective Samarium-Mediated Allylic Sulfone Reductions, Cody Schwans
WWU Graduate School Collection
A series of allylic sulfones were synthesized containing a stereodirecting group and chelating element and subjected to samarium diiodide reductions in the presence of a proton donor. The resulting products could be obtained with high regioselectivity (no less than 95:5) and high diastereoselectivity (>10:1) that correlated with the size of the stereodirecting group. A mechanism is proposed that includes loss of the sulfone and formation of a chelated organosamarium intermediate followed by intramolecular protonation by a samarium-bound proton source. In this way, both the regioselectivity and absolute stereochemistry of the resulting products are explained.
Evaluating Leaf Trait Variation In High Elevation Bristlecone Pine (Pinus Longaeva) Under Increasing Water Stress: Insights From Needle Length, Stomatal Density, And Cambial Growth, Audrey Salerno
WWU Graduate School Collection
Increasing aridification caused by climate change is altering growth patterns in trees. There is revived attention on how foliar traits respond to climate and the relationship of these traits to ring width. Bristlecone pine (Pinus longaeva, DK Bailey), a long-lived conifer found at high elevations in the cool and dry intermountain west of America, is used in paleoclimate reconstructions by measurement of their annually resolvable tree rings. The species also has annually datable needles retained on their branches for an average of 45 years making it the ideal subject for research on foliar trait and growth relationships under …
Connections Between Eruption Style And Magmatic Reservoir Evolution: Insights From Augustine Volcano, Alaska, Usa, Mahinaokalani G. Robbins
Connections Between Eruption Style And Magmatic Reservoir Evolution: Insights From Augustine Volcano, Alaska, Usa, Mahinaokalani G. Robbins
WWU Graduate School Collection
At a single volcano, eruptive behavior can change through time as the plumbing system evolves. Augustine Volcano, a frequently active intermediate stratovolcano in the Alaska-Aleutian arc (USA), is an ideal setting to investigate magma reservoir processes due to its frequent modern and Holocene eruption history. Its most recent 2006 CE eruption included mixed effusive and moderately explosive (VEI 3) events and has been studied in detail. Proximal fall deposits from this eruption were generally mixed fine ash to lapilli with variable thickness, but typically ~5 cm on the island (Wallace et al., 2010). The Pre-contact “Tephra M” was deposited by …
Using Qm/Mm Methods To Explore Sortase Enzyme Intermediates, Kinetics, And Stability, Kyle Whitham
Using Qm/Mm Methods To Explore Sortase Enzyme Intermediates, Kinetics, And Stability, Kyle Whitham
WWU Graduate School Collection
Biochemistry has seen advancements in methods and understanding of the inner workings of proteins, yet biochemists struggle to see real time reaction pathways of protein intermediates. This is where computational chemistry comes in and fills in the holes in knowledge through the use of Quantum Mechanical (QM) models. QM chemistry alone does not give results in a reasonable timescale to predict protein chemistry in a reasonable amount of time. Computational chemistry methods such as Quantum mechanical (QM)/ Molecular Mechanical (MM) (QM/MM), allow us to split the in-silico system into two regions that utilize a fast MM force field region and …
Generations Of Stewards: Re-Indigenizing Youth Leadership, Learning, And Conservation Education, Drew Slaney
Generations Of Stewards: Re-Indigenizing Youth Leadership, Learning, And Conservation Education, Drew Slaney
WWU Graduate School Collection
My thesis is an exploratory case study into epistemologies (or worldviews) supported by organizations and agencies that develop outdoor conservation and education programs for Native youth called Native Youth Stewardship Programs (NYSPs). This subject relies on the content developed by Medin and Bang (2014) who state that an under-representation of Indigenous peoples in Science, Technology, Engineering, and Mathematics (STEM) fields is largely the result of epistemological conflicts between educators and Indigenous students. I hypothesize that there is a considerable epistemological difference between the conservation entities developing programs to engage Native youth. These differences may create significant barriers with youth recruitment, …
Class A Sortases: Structures And Alternative Substrate Binding And Cleavage, Brandon Vogel
Class A Sortases: Structures And Alternative Substrate Binding And Cleavage, Brandon Vogel
WWU Graduate School Collection
Sortases, consisting of classes A-F, are cysteine transpeptidases found in the cell wall of Gram-positive bacteria. They play a crucial role in ligating proteins to the cell wall that are responsible for cell adhesion, immune evasion, host cell invasion, and nutrient acquisition through a transpeptidation reaction. Consequently, they are an attractive therapeutic target. Class A sortases are also utilized in protein engineering applications such as sortase-mediated ligations and sortagging. Despite extensive research in the past two decades, gaps persist in understanding how class A sortases recognize their substrates, primarily due to a lack of structural information on sortases non-covalently bound …
The Race Toward Carbon Neutral Ecotourism: Leveraging Life Cycle Analysis And Natural Climate Solutions For A Community Adventure Event, Ted Tarricone
The Race Toward Carbon Neutral Ecotourism: Leveraging Life Cycle Analysis And Natural Climate Solutions For A Community Adventure Event, Ted Tarricone
WWU Graduate School Collection
Global tourism is an interconnected framework of multiple industries that is influenced by and has impacts on economic, social, and environmental structures. Currently, tourism accounts for roughly 8% of global greenhouse gas emissions, which is expected to grow with industry expansion. To develop a scalable system for ecotourism assessment, emission reduction, and solutions to meet carbon neutrality, a small (n=3894 participants) adventure relay race named Ski to Sea in Bellingham, WA was studied. A life cycle analysis (LCA) conducted on the race showed similar proportional results to other tourism LCAs, where transport made up over 80% of the 325 tonnes …
A Mixed-Methods Study Of Geoscience Identity, Race/Ethnicity, And Gender In Senior Undergraduate Geoscience Majors, Willa Rowan
A Mixed-Methods Study Of Geoscience Identity, Race/Ethnicity, And Gender In Senior Undergraduate Geoscience Majors, Willa Rowan
WWU Graduate School Collection
I conducted a mixed methods study of geoscience identity in undergraduate students to examine the cultural and social aspects of geoscience degree programs. White students are overrepresented in geoscience, and a priority of anti-racism efforts in the field is listening to the experiences of students who are Black, Indigenous, or people of color (BIPOC) to better inform equity and inclusion goals. Structural racism in geoscience pushes BIPOC students out of the field, and it can be better understood by studying socially constructed aspects of learning such as geoscience identity. This study is the first to measure geoscience identity with a …
U-Pb Zircon Geochronology And Structure Of Regional Blueschist Units In The Easton Metamorphic Suite, Northwest Cascades, Wa, Katherine Lang
U-Pb Zircon Geochronology And Structure Of Regional Blueschist Units In The Easton Metamorphic Suite, Northwest Cascades, Wa, Katherine Lang
WWU Graduate School Collection
The Easton metamorphic suite of the Northwest Cascades Thrust System (NWCS) is a well-preserved subduction accretion complex in Washington State. The regional blueschist units of the Easton metamorphic suite include the Mt. Josephine semi-schist, Darrington Phyllite, and Shuksan greenschist/blueschist and all are interpreted to have accreted after the onset of Jurassic subduction beneath North America. This study uses zircon U-Pb geochronology, structure, and field observations to test the regional correlations between units in the Easton metamorphic suite and address models for the timing of subduction accretion along the North American margin in the Late Jurassic – Early Cretaceous. The results …