Earth Sciences Commons^™

Alpine Shrub Tundra Water Storage And Runoff Dynamics In The Mackenzie Mountains, Sahtú Territory, Nt, Geoffrey Kershaw

Theses and Dissertations (Comprehensive)

Alpine regions receive large volumes of precipitation and are important to local and regional water balances, particularly during baseflow periods of winter cold and summer drought when the larger basin area is frozen and/or water limited. Alpine headwaters in western Canada are expected to warm and receive more precipitation during the coming decades, with implications for groundwater recharge and streamflow generation within these systems and the regional river networks to which they contribute. Throughout the North, thawing peat plateaus and other ice-rich permafrost features are resulting in an increased extent of thermokarst and wetland land cover. This transition places infrastructure …

Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok

Theses and Dissertations (Comprehensive)

As park visitation increased to Point Pelee National Park up until its peak in 1963, the installation of infrastructure for the purpose of supporting the recreational interest grew with it. At Northwest Beach, large parking lots were built into the coastal landscape and by the 1970s large areas of sand dunes continued to be heavily impacted by the installation of visitor associated infrastructure. The infrastructure resulted in the stabilization of sand on the beach side of the parking lot, resulting in an artificially stabilized and heavily vegetated dune. Over the last few decades, the park slowly reduced the size and …

Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel

Biological Sciences Faculty Publications

Establishment and survival of plant species in systems with dominant environmental drivers (i.e. factors that exert disproportionate control over species establishment and survival) is often thought to be dominated by one master variable. In forested wetlands such as mangroves, hydrology is typically considered the dominant limiting driver. At the same time, light is a major driver of plant community dynamics, with some of the best understood plant life-history tradeoffs related to fast growth under high-light conditions versus survival under low-light conditions. Yet light is given relatively limited consideration in mangrove research compared to other drivers. Understanding the relative importance of …

Microplastics In Mangrove Sediments At Maeklong River Mouth, Samut Songkhram Province, Pattraporn Chaisanguansuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics are omnipresent in our environment. Living organisms were affected by microplastic pollution. This study was investigated microplastic in mangrove environments because there are accumulated various substances from land and sea. Moreover, mangrove is an important ecosystem that is a habitat for marine life and benthic organism. Our study area is the Maeklong River mouth, Samut Songkhram Province, Thailand. Surface sediments from 3 stations were collected from the Maeklong River area and 2 core sediments were collected from the Maeklong River mouth and the Queen Sirikit Park. Sediment samples were analyzed by Loss on ignition (LOI) and grain size distribution. …

Remote Sensing And Luminescence Dating Of Archaeological Sites In Buriram Province, Northeastern Thailand, Sutthikan Khamsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aims to apply remote sensing and luminescence dating to study archaeological sites in Buriram Province, Northeastern Thailand. There are three main objectives including 1) to model the ancient path from the mountain passes along the Dângrêk mountain to ancient community on Angkor Highland or Northeast Thailand, 2) to directly date slag from the ancient iron smelting site at Ban Sai To 7, and 3) determine the terminal age of Ban Sai To 7 site using technical ceramics. Firstly, the results of the GIS-based least cost path (LCP) route, using topographic factors, show that Ta Muen, Sai Ta Ku, …

Sea Surface Temperatures And Vertical Wind Shear As Precursors To Tropical Cyclone Activity In The Caribbean And An Expanding Main Developing Region, Keneshia Hibbert

Dissertations and Theses

Sea surface temperatures and vertical wind shear are essential to tropical cyclone formation. TCs need warm SSTs and low shear for genesis. Increasing SSTs and VWS changes influence storm development. This work analyzes SST and VWS trends for the Caribbean, surrounding region, and the Atlantic hurricane main developing region from 1982 to 2020. Storm intensity increases significantly during this period. Annual and seasonal trends show regional SSTs in the MDR are warming annually (0.0219°C yr^-1) and per season (0.0280°C yr^-1). Simultaneously, VWS decreases during the late rainfall season at 0.0556m/s yr^-1 in the MDR and …

Evaluation Of Snow And Streamflow In The National Water Model With Analysis Using Machine Learning, Engela Sthapit

Dissertations and Theses

Snow has great influence on land-atmosphere interactions and snowmelt from the mountains is a vital water source for downstream communities dependent on snow fed lakes, rivers and streams. This study explored the snow and streamflow prediction capabilities of process-based numerical prediction and data-driven machine learning models.

The overall goal of this study was to understand the deficiencies in the NOAA’s National Water Model (NWM) to represent snow, subsequently streamflow, and recognize the areas where it could be improved for future model developments. The goal was also to evaluate if the recent advancements in machine learning techniques is useful for predicting …

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …

Analysis Of Sunscreens And Antibiotics In Groundwater During The Covid-19 Pandemic In The Riviera Maya, Mexico, Jackie Cooney

Graduate Research Theses & Dissertations

Sunscreens and antibiotics are contaminants of emerging concern in groundwater, especially in areas with high tourism. The Riviera Maya in Quintana Roo, Mexico, is an international travel destination with a popular aquatic tourism industry. The region experienced a significant decrease in tourist visits during the COVID-19 pandemic, setting up a natural experiment to characterize the baseline contamination of groundwater in the absence of tourists. Additionally, municipalities installed new sewage disposal systems to combat the poor water quality due to inadequate septic systems and wastewater treatment plants. Water samples were collected during the pandemic from March 2020 to July 2021 from …

Transport Of Polyethylene Microplastic Spheres In A Sandy Aquifer, Alyssa Marie Graveline

Graduate Research Theses & Dissertations

Microplastic particles are currently listed as a Contaminant of Emerging Concern (CEC) since they are in much of Earth’s water systems and recent studies indicate plastic particles can sorb toxic contaminants. Microplastics (MP) are defined as plastic particles under 5 mm in length. Currently, there is a paucity of data on the transport of MP in the subsurface. This study investigated the transport, filtration, retardation, and influence of 5-100ߎm plastic polyethylene spheres in a shallow sandy aquifer over a distance of 1m by utilizing two forced hydraulic gradient tracer studies. Slug tests were used to estimate hydraulic conductivity prior and …

Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig

Graduate Research Theses & Dissertations

Prairie restoration is important for reversing the loss of biodiversity and repairing ecosystem functions humanity is dependent on diverse ecosystems. This study looks at the impact of the beginning phases of prairie restoration on groundwater geochemistry and microbial communities the relationship between them. This research project studied the geochemistry and microbial communities in five wells before, during, and after the beginning phases of the first year of a prairie restoration on the Northern Illinois University campus. Water samples were collected bimonthly for a year and analyzed on an Ion Chromatograph. Microbial samples were collected monthly and underwent DNA extraction, amplification, …

Comparison Of Topsoil Moisture In E3sm Model Simulations And In-Situ Observations Over Illinois, Jacinda Lee Mayer

Graduate Research Theses & Dissertations

Soil moisture stimulates land-atmosphere interactions by modifying energy and water fluxes in the boundary layer and it plays an important role in climate change studies. The objective of this research is to quantify the spatial and temporal variations of the Illinois Climate Network’s (ICN) observed topsoil moisture, as well as evaluate how accurately the new climate model, E3SM, is simulating soil moisture compared to the observed data during 2003-2014. Observed topsoil moisture averaged over growing season during the 12-year period indicates a general dry-north and wet-south pattern in Illinois, and northeast and southwest become drier with the progression of the …

Climate Change Impacts On Baseflow Contributions In A Semi-Arid, Snowmelt-Dominated Basin Within The Upper Colorado River Basin, Kaelyn Quinlan

Graduate Research Theses & Dissertations

The Upper Colorado River Basin (UCRB) is a significant water resource in the southwestern United States, providing water to Colorado, New Mexico, Utah, and Wyoming. (Reclamation, 2012). Communities and industries within these states are dependent on the Colorado River’s water availability and accessibility. Growing population and development demands, in conjunction with climate change, can have drastic consequences for the ecosystems and municipalities dependent on these reservoirs. It is critical that as watersheds within this region are strained under increased demands and decreased inputs, water use practices use informed decision-making to manage the budget and quality of its water resources.

I …

Exploring The Morphometrics Of The Diatom Fragilariopsis Kerguelensis As A Proxy For Paleo-Sea Surface Temperature In The Late Pleistocene-Holocene Southern Ocean, Joseph Anthony Ruggiero

Graduate Research Theses & Dissertations

The Southern Ocean has played a large role in moderating global climate since its inception in the Oligocene. With the onset of anthropogenic global warming, it is now more necessary than ever that we understand the world’s climate during periods of rapidly fluctuating temperature in the past. Climatic forecasts are informed by paleoenvironmental conditions of the past during these turbulent periods, which we can examine using proxy data. This thesis assesses a potential proxy for Sea Surface Temperature (SST) through morphometric analysis of the Southern Ocean diatom Fragilariopsis kerguelensis in the Amundsen Sea, West Antarctica. This proxy is based off …

Development Of Regional Landslide Susceptibility Models: A First Step Towards Model Transferability, Gina M. Belair

Graduate Student Theses, Dissertations, & Professional Papers

Landslides are a globally pervasive problem with the potential to cause significant fatalities and economic losses. Although landslides are widespread, many at-risk regions may not have the high-quality data or resources used in most landslide susceptibility analyses. This study aims to develop regional susceptibility relationships that are versatile and use publicly available data and open-sourced software. Logistic Regression and Frequency Ratio susceptibility relationships were developed in 23 regions in Washington, Utah, North Carolina, and Kentucky, with a region referring to a unique area and data combination. Regions were diverse in their geology, morphology, climate, and nature and quality of their …

1-D Crustal Seismic Velocity Models For West-Central And Western Montana, Courtenay Duzet

Graduate Student Theses, Dissertations, & Professional Papers

In seismically active areas with infrequent, large-magnitude earthquakes, high-quality seismic data are critical for determining high-resolution, accurate seismic velocity models. Here, we present a new local-scale seismic velocity model for the crust in west-central Montana as well as a new regional-scale seismic velocity model for the crust and upper mantle across broader western Montana. The new models are constrained by phase arrivals from several passive seismic networks, including the University of Montana Seismic Network (UMSN), the Montana Regional Seismic Network (MRSN), the Advanced National Seismic System (ANSS), temporary deployments by the United States Geological Survey (USGS), and the USArray Transportable …

Future Climate Streamflow Estimation In The Donnelly River Catchment, Justin Hughes, Bill Wang

Natural resources commissioned reports

The Donnelly River is located in the south-west of Western Australia. An irrigation development has been proposed in the catchment that would extract water from the Donnelly River and store this in an off stream reservoir for irrigation use. Given the known issues related to non-stationarity and hydrological prediction, the Department of Primary Industries and Regional Development (DPIRD) contracted CSIRO to review the hydrological model that was used to estimate future climate streamflow in the Donnelly River. This model was owned and operated by the Department of Water and Environmental Regulation (DWER). The CSIRO review of the model, which also …

Interaction With Augmented Reality Sandbox Does Not Produce Greater Gains In Topographic Map Skills For Undergraduate Students, Celeste Kenworthy

Honors Program: Senior Projects (Public)

The augmented reality (AR) sandbox allows students to interact with topographic maps in a 3D space. Being able to understand topographic maps is important to geologists and they are taught in many introductory geology courses. Recent research has focused on whether the AR sandbox can improve students’ topographic map skills. Previous studies have found that students who interact with the AR sandbox do not score significantly better on topographic map assessments (TMAs) than their peers. One proposed reason for this is the limited time students have to interact with the AR sandbox. This study sought to address this by creating …

การจำลองการรั่วไหลของน้ำมันบริเวณอ่าวไทยตอนบน, กิตติยา แย้มภิรมย์ศรี

Chulalongkorn University Theses and Dissertations (Chula ETD)

สถิติการเกิดน้ำมันรั่วไหลในประเทศไทยตั้งแต่อดีตถึงปัจจุบันของกรมเจ้าท่า พบว่าเกิดน้ำมันที่รั่วไหลในทะเลอ่าวไทยตอนบนหลายครั้ง โดยมีสาเหตุมาจากเรือขนส่งสินค้า เรือขนถ่ายน้ำมัน เกิดอุบัติเหตุกลางทะเล อันเป็นผลมาจากความชำรุดของอุปกรณ์เดินเรือ หรือสภาพภูมิอากาศที่ไม่ดีต่อการเดินเรือ ยังส่งผลกระทบต่อชีวิต ทรัพย์สิน และสิ่งแวดล้อมอย่างมาก เพราะบริเวณอ่าวไทยตอนบนมีพื้นที่ชุมชนชายฝั่งทะเล และแหล่งเพาะพันธุ์สัตว์น้ำ การศึกษาในครั้งนี้มีวัตถุประสงค์เพื่อศึกษาการจำลองการรั่วไหลของน้ำมันบริเวณอ่าวไทยตอนบน โดยใช้แบบจำลองทางคณิตศาสตร์ในการคาดการณ์การเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเล ประกอบด้วยแบบจำลอง 3 ชนิด คือแบบจำลอง SWAN ใช้ในการจำลองคลื่นที่เกิดจากลม, แบบจำลอง Delft3D ใช้ในการจำลองกระแสน้ำเนื่องจากอิทธิพลของน้ำขึ้นน้ำลงและคลื่นลม และแบบจำลอง GNOME ใช้ในการจำลองการรั่วไหลของน้ำมันในทะเลบริเวณอ่าวไทยตอนบน ผลของแบบจำลองแบ่งออกเป็น 2 ส่วน คือ การจำลองคลื่นและกระแสน้ำ และการจำลองการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลอ่าวไทยตอนบน ความสูงคลื่นนัยสำคัญเป็นผลที่ได้การจำลองคลื่นด้วยแบบจำลอง SWAN มีการปรับเทียบและสอบทานข้อมูลจากแบบจำลองกับข้อมูลตรวจวัดจากทุ่นสมุทรศาสตร์ของสำนักงานพัฒนาเทคโนโลยีอวกาศและภูมิศาสตร์สารสนเทศ ในปี พ.ศ.2540 – 2545 ที่สถานีสถานีหัวหิน, สถานีเพชรบุรี และสถานีเกาะสีชัง กระแสน้ำเนื่องจากน้ำขึ้นน้ำลงและกระแสน้ำสุทธิที่เป็นผลรวมของน้ำขึ้นน้ำลงและคลื่นลมจากแบบจำลอง Delft3D ถูกปรับเทียบและสอบทานโดยใช้ระดับน้ำจากแบบจำลองกับข้อมูลระดับน้ำทำนายของกรมอุทกศาสตร์ กองทัพเรือ ในปี พ.ศ. 2549 – 2559 ที่สถานีหัวหิน, สถานีสันดอนเจ้าพระยา, สถานีเกาะสีชัง และสถานีอ่าวสัตหีบ จากการศึกษาคลื่นและกระแสน้ำพบว่ากระแสน้ำที่เป็นอิทธิพลหลักบริเวณอ่าวไทยตอนบนคือกระแสน้ำเนื่องจากอิทธิพลของน้ำขึ้นน้ำลง จึงใช้กระแสน้ำเนื่องจากน้ำขึ้นน้ำลงในการศึกษาการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลต่อไป การศึกษาการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลอ่าวไทย ทำการปรับเทียบและสอบทานแบบจำลอง GNOME ด้วยข้อมูลภาพถ่ายดาวเทียมของสำนักงานพัฒนาเทคโนโลยีอวกาศและภูมิสารสนเทศ (GISTDA) ในช่วงเกิดเหตุการณ์น้ำมันรั่วบริเวณปากแม่น้ำเจ้าพระยา วันที่ 3 ธันวาคม พ.ศ.2562 พบว่าการเคลื่อนที่ของคราบน้ำมันมีทิศทางสอดคล้องกับทิศทางของลม ในการศึกษานี้ประยุกต์ใช้แบบจำลองโดยการวิเคราะห์การเคลื่อนที่ของคราบน้ำมันในช่วงน้ำเกิดและน้ำตายรายเดือน ทำให้สามารถประมาณช่วงเวลาและตำแหน่งที่น้ำมันเคลื่อนที่กระทบชายฝั่งทะเล และสรุปได้ว่าการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลมีการเปลี่ยนแปลงตามปัจจัยของชนิดน้ำมัน, คุณสมบัติการแพร่กระจายของน้ำมัน, ข้อมูลลม และข้อมูลกระแสน้ำในทะเล

ปัจจัยคัดสรรที่มีความสัมพันธ์กับพฤติกรรมการป้องกันการติดเชื้อไวรัสโคโรนา 2019 ของอาสาสมัครฉุกเฉินการแพทย์ ประเทศไทย, จารุวรรณ พฤทธยานันต์

Chulalongkorn University Theses and Dissertations (Chula ETD)

การวิจัยครั้งนี้เพื่อศึกษาความสัมพันธ์และอำนาจทำนายระหว่างความรู้ ทัศนคติ การรับรู้โอกาสเสี่ยงของการเกิดโรค การรับรู้ความรุนแรงของโรค การรับรู้ประโยชน์ของการปฏิบัติเพื่อป้องกันโรค การรับรู้อุปสรรคของการปฏิบัติเพื่อป้องกันโรค พฤติกรรมเกี่ยวกับการจัดการความรู้ แรงสนับสนุนทางสังคม การเปิดรับข่าวสาร และพฤติกรรมกับการป้องกันการติดเชื้อไวรัสโคโรนา 2019 ของอาสาสมัครฉุกเฉินการแพทย์ ประเทศไทย การวิจัยแบบบรรยายเชิงความสัมพันธ์ กลุ่มตัวอย่าง คือ อาสาสมัครฉุกเฉินการแพทย์ ในประเทศไทย จำนวน 165 คน คัดเลือกกลุ่มตัวอย่างด้วยวิธีการสุ่มแบบหลายขั้นตอน เครื่องมือวิจัย คือ แบบสอบถามออนไลน์ 8 ส่วน สถิติที่ใช้ในการวิเคราะห์ข้อมูล ได้แก่ สถิติเชิงพรรณนา ค่าสัมประสิทธิ์สหสัมพันธ์ของสเปียร์แมน และสถิติถดถอยพหุคูณแบบขั้นตอน ผลการวิจัย 1) ปัจจัยด้านทัศนคติ การรับรู้โอกาสเสี่ยงของการเกิดโรค การรับรู้ความรุนแรงของโรค การรับรู้ประโยชน์ของการปฏิบัติเพื่อป้องกันโรค การรับรู้อุปสรรคของการปฏิบัติเพื่อป้องกันโรค พฤติกรรมเกี่ยวกับการจัดการความรู้ แรงสนับสนุนทางสังคม และการเปิดรับข่าวสาร มีความสัมพันธ์ทางบวกกับพฤติกรรมกับการป้องกันการติดเชื้อไวรัสโคโรนา 2019 อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 2) ปัจจัยที่ร่วมกันทำนายพฤติกรรมกับการป้องกันการติดเชื้อไวรัสโคโรนา 2019 ของอาสาสมัครฉุกเฉินการแพทย์ อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 ได้แก่ แรงสนับสนุนทางสังคม การรับรู้ประโยชน์ของการปฏิบัติเพื่อป้องกันโรค และการเปิดรับข่าวสาร โดยสามารถร่วมกันทำนายได้ร้อยละ 66.7

Investigation Of Mass Wasting In The Vicinity Of Khao Kho, Central Thailand Using Time – Series Insar Technique, Nuttavit Kumvijairat

Chulalongkorn University Theses and Dissertations (Chula ETD)

The application of time-series InSAR has been employed for investigation of mass wasting in the Khao Kho and Phetchabun mountain range. The objective of this study is to Investigation of mass wasting by SAR data between 2015 to 2018 and classification of mass wasting by displacement rate millimeter/year. This study using active remote sensing data, which is Synthetic Aperture Radar (SAR) satellite imagery from Sentinel-1A and Sentinel-1B satellites. Result from PSInSAR analysis yielded a total of 7,354 PS points for ascending orbit, and 8,984 PS point for descending orbit. The average ground displacement rate result from ascending orbit is 65.19 …

Geomorphological Change Of The Upper Yom River In Phrae Province, Kakkhanang Na Nan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Yom River is the main tributary of the Chao Phraya River; the upper Yom River flows through Phrae Province. This research selected the upper Yom River because of meander processing in an active basin, which rapidly migrates and changes landforms all the time, The object of this research is to study geomorphological change, thickness and behavior of the upper Yom River in Phrae Province. By assessing aerial photographs and satellite images from 1954 to 2019, the researchers were able to interpret the geological changes that occurred over the past 65 years. The study identified several geomorphological changes from channel migration …

Typology And Formation Of Pothole Along The Mekong River And Erosional Remnant In Sandstone Of Khorat Group, Ubon Ratchathani Province, Northeastern Thailand, Sirawat Udomsak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phachan Samphanbok Geopark showcases fascinating erosional features, such as a multitude of potholes in the Mekong River. Additionally, it is home to the largest pedestal rock in Thailand, located in Ubon Ratchathani province in the northeastern part of the country, near the border between Thailand and Laos PDR. The formation of potholes is attributed to the erosive force of swirling sediment within fractures caused by vortex currents. In this research study on pothole evolution, the potholes in the Mekong River were categorized into two main groups: structural control potholes and non-structural control potholes. These types were further divided into five …

Performance Of Black Soldier Fly Frass Fertiliser On Maize (Zea Mays L.) Growth, Yield, Nutritional Quality, And Economic Returns, C. M. Tanga, D. Beesigamukama, M. Kassie, P. J. Egonyu, Changeh J. Ghemoh, Kiatoko Nkoba, S. Subramanian, A. O. Anyega, S. Ekesi

All Peer-Reviewed Publications

Although the black soldier fly frass fertiliser (BSFFF) is globally recognised as a promising and potential high-quality organic fertiliser, there is inadequate information on its impact on the growth performance and nutritional status of maize. Furthermore, no information exist on their combination with mineral fertiliser (NPK) as well as economic impact on maize production. This study evaluated the comparative impact of BSFFF, NPK and commercial organic fertiliser (Evergrow®) on growth, nitrogen use efficiency, yield, nutritional quality, and profitability of maize under greenhouse conditions. The treatments included: (1) sole application of BSFFF, conventional compost of brewers’ spent grain (BSG), Evergrow, and …

The Derivation Of Geologic Ecosystem Services From Geodiversity In The Black Hills Region Of South Dakota And Wyoming, James Campbell Cooke

Dissertations and Theses

The ecosystem services approach seeks to recognize the benefits that people obtain from ecosystems, in order to highlight society’s dependence on natural systems. Ecosystem services fall into four categories: provisioning, regulating, cultural, and supporting services. Most of the ecosystem services research literature is focused on services that arise from biotic components of ecosystems. Ecosystems are dynamic complexes of biotic communities and their physical, non-living environment, interacting as a functional unit. The emphasis on biotic ecosystem services leaves understudied and undervalued the role of the abiotic, physical environment, especially in providing geologic ecosystem services. Geologic ecosystem services have been the focus …

Late Quaternary Glacier Fluctuations At Picayune Lake, Northern California, Aidan Patrick Cowan

Cal Poly Humboldt theses and projects

The Klamath Mountains are a 233-km-long (north to south) mountain range located in northern California that shows extensive geomorphic evidence of Pleistocene glaciation. Within the Klamath’s there are many highland lakes, which record evidence of glacial deposition, one of which is Picayune Lake. Lake sediment data collected from Picayune Lake offers insights into the glaciation, and broader depositional history of the Picayune Lake Valley, as well as the climate history of the Klamath Mountains region. I measured magnetic susceptibility, loss on ignition, and grain size in sediment cores and used radiocarbon dating to determine a chronology of glacier fluctuations in …

Geomorphic Evaluation Of The Goose Lake Fault And Fluvial Terraces At The Yager Creek–Van Duzen River Confluence, Northern Coastal California, Samuel E. Bold

Cal Poly Humboldt theses and projects

Upper-plate deformation in the southern Cascadia subduction zone is dynamic and complex, situated in the transition between northward translation to westward convergence. Rock uplift and incision rates characteristic of this dynamic region are preserved in suites of fluvial and marine terraces. Fluvial terraces at the Yager Creek–Van Duzen River confluence record fluvial incision rates, and are crosscut by the understudied Goose Lake fault, an upper plate structure. In this work, I use high resolution lidar imagery to map terrace surfaces, and use optically stimulated luminescence, radiocarbon, and Beryllium-10 geochronology to bracket terrace ages and calculate incision and slip rates. With …

Boron Isotopes In Boninites Document Rapid Changes In Slab Inputs During Subduction Initiation, Hong-Yan Li, Xiang Li, Jeffrey G. Ryan, Chao Zhang, Yi-Gang Xu

School of Geosciences Faculty and Staff Publications

How subduction-related magmatism starts at convergent plate margins is still poorly understood. Here we show that boron isotope variations in early-formed boninites from the Izu-Bonin arc, combined with radiogenic isotopes and elemental ratios document rapid (~0.5 to 1 Myr) changes in the sources and makeup of slab inputs as subduction begins. Heterogeneous hornblende-granulite facies melts from ocean crust gabbros ± basalts fluxed early melting to generate low silica boninites. Hydrous fluids from slab sediments and basalts later fluxed the low silica boninites mantle source to produce high silica boninites. Our results suggest that initially the uppermost parts of the slab …

The Legacy Of Hurricanes, Historic Land Cover, And Municipal Ordinances On Urban Tree Canopy In Florida (United States), Allyson B. Salisbury, Andrew K. Koeser, Richard J. Hauer, Deborah R. Hilbert, Amr H. Abd-Elrahman, Michael G. Andreu, Katie Britt, Shawn Landry, Mary G. Lusk, Jason W. Miesbauer, Hunter Thorn

School of Geosciences Faculty and Staff Publications

Urban Tree Canopy (UTC) greatly enhances the livability of cities by reducing urban heat buildup, mitigating stormwater runoff, and filtering airborne particulates, among other ecological services. These benefits, combined with the relative ease of measuring tree cover from aerial imagery, have led many cities to adopt management strategies based on UTC goals. In this study, we conducted canopy analyses for 300 cities in Florida to assess the impacts of development practices, urban forest ordinances, and hurricanes on tree cover. Within the cities sampled, UTC ranged from 5.9 to 68.7% with a median canopy coverage of 32.3% Our results indicate that …

Classification Of Seismic Activity At The Lazufre Volcanic System, Based On 2011 To 2012 Data, Heather Mcfarlin, Glenn Thompson, Stephen R. Mcnutt, Jochen Braunmiller, Michael E. West

School of Geosciences Faculty and Staff Publications

The Lazufre Volcanic System (LVS), on the border of northern Chile and Argentina, is an active complex of two volcanoes, Lastarria to the north and Cordón del Azufre to the south. The LVS is not regularly monitored with any scientific equipment despite being recognized as a top ten volcanic hazard in Argentina by the Observatorio Argentino de Vigilancia Volcánica of the Servicio Geológico y Minero Argentino. The system has shown unusual inflation signatures observed in InSAR but the level of seismic activity and its spatial and temporal distribution were unknown due to the lack of a permanent local seismic network. …