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

Physical Sciences and Mathematics Commons

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

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama May 2023

Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama

Undergraduate Honors Theses

The Salton Sea is a closed hypersaline lake in Southern California that has been receiving little input over the past few decades, leading to desiccation that is rapidly increasing every year. This large-scale evaporation of the sea has led to increased dissolved solutes, high salinity, and gypsum blooms. Gypsum blooms, the precipitation of gypsum (CaSO42H2O) in the sea, have been a prominent facet of the sea and their distribution is well known. However, much of their chemistry and potential health hazards are still undetermined. Potential health effects from gypsum salt, an atmospheric dust particle present at the sea, have known …


Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman Apr 2022

Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman

Undergraduate Honors Theses

137Cs is a radioactive trace metal (T1/2 = 30 y) that was dispersed globally by nuclear weapons testing in the 1950s-1960s. Prevailing winds and precipitation systems caused some areas far from the test sites to receive significant fallout, which is still easily measured in soils, sediments and even some vegetation in the Eastern United States. Recent work near Chernobyl and Fukushima indicates that trace levels of 137Cs can harm insects, pollination services, and other ecological functions. In areas with low soil potassium, 137Cs is cycled in vegetation; however, soil potassium alone doesn't consistently predict the 137 …


Developing And Validating A Standard Operating Procedure For Quantitative Analysis Using Central Washington University's X-Ray Diffractometer, Katherine Lucas Jan 2022

Developing And Validating A Standard Operating Procedure For Quantitative Analysis Using Central Washington University's X-Ray Diffractometer, Katherine Lucas

Undergraduate Honors Theses

X-ray diffraction (XRD) is widely applied in a variety of disciplines to identify crystalline solids in a powdered sample. Recent software advances have made quantitative analysis of samples easier and more accessible, but the quality of the result depends on the sample preparation and data collection procedure. This project focuses on testing methods of sample preparation and XRD data collection and analysis to lay the groundwork for refinement of the existing standard operating procedures at CWU. First, I determined the ball mill grinding time necessary to powder different mineral samples. The addition of hand grinding to ball mill-ground samples produced …


Three Centuries Of Vegetation Change In The William & Mary College Woods Reconstructed Using Phytoliths, Timothy Terlizzi May 2021

Three Centuries Of Vegetation Change In The William & Mary College Woods Reconstructed Using Phytoliths, Timothy Terlizzi

Undergraduate Honors Theses

The College Woods, west of William & Mary’s campus, consists of ~900 acres of protected southern mixed hardwood forest. The woods surround Lake Matoaka, a former millpond established in ~1700. Despite the rich history of the area, little is known about how the dominant vegetative landcover has shifted over the last 300 years. This study set out to quantify the modern vegetation within the College Woods via the phytolith assemblages within the soil and identify shifts in the assemblages since the creation of Lake Matoaka and whether these changes are distinct from the vegetation that existed in the area before …


A Comparative Study To Calculate Hydraulic Conductivity In Ultisols On An East Tennessee Hillslope, Sydney A. Lawson May 2015

A Comparative Study To Calculate Hydraulic Conductivity In Ultisols On An East Tennessee Hillslope, Sydney A. Lawson

Undergraduate Honors Theses

This study compares four different methods to measure hydraulic conductivity (K) at two sites on the East Tennessee State University Valleybrook Campus. It compares the K values to each other, to the different K values between the two sites, and to United States Department of Agriculture (USDA) K values. Two field methods, Well Bail Test and Auger Hole Test, and two lab methods, Constant Head Permeameter Test and Grain Size Distribution Test (GSD), were performed on the clay rich Ultisol soils on an East Tennessee hillslope in the Valley and Ridge Physiographic Province. One site was located close to a …


Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar Jan 2013

Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar

Undergraduate Honors Theses

The eastern portion of Washington State's Cascade Range is a place not previously examined for rock glaciers, due to proximity to the Pacific Ocean and its associated marine-influenced climate. The objectives of this study were to determine spatial, activity, and genesis patterns, and paleoclimatic implications of Eastern Cascade rock glaciers. Using Google Earth, I found 103 rock glaciers in the study area. Rock glaciers are more common further east of the Cascade crest and more north in latitude, with the largest concentrations occurring east of Lake Chelan (22) and in the Pasayten Wilderness (28) in the North Cascades. None were …