Earth Sciences Commons^™

Effects Of Demineralization Protocols On Hydrogen And Oxygen Isotope Ratios In Fossil Bone Collagen, Linda M. Reynard

Boise State University Publications and Presentations

The effect of three commonly used preparation protocols on bone collagen δ2H and δ18O values was investigated, using six generally well-preserved faunal bones (cattle, bison, horse) ranging in age from the Holocene to Late Pleistocene. The treatments tested were ethylene diamine tetraacetic acid demineralization without gelatinization and hydrochloric acid demineralization with and without gelatinization. There are significant shifts in δ18O values among preparation methods. No systematic shifts in bone collagen δ2H values were noted among the three treatments, and most offsets were low (< 2–3 ‰) and smaller than typical measurement uncertainties. A few sample/treatment combinations yielded slightly higher inter-treatment δ2H differences (∼ 5–7 ‰). Lower mass fraction of hydrogen in …

Quantifying The Impacts Of Land Use And Land Cover Change On Urbanizing Agricultural Systems, Carli Beisel

Boise State University Theses and Dissertations

Western water supplies are increasingly stressed by the compounding impacts of population growth, urbanization, and climate change. Rising temperatures in Idaho are shifting precipitation patterns, with more falling as rain rather than snow. This reduces snowpack and the resulting snowmelt, which serves as the predominant water source for agriculture. At the same time, urbanization of agricultural land decreases surface permeability, replaces irrigated fields, and amplifies the impacts of climate change. The Treasure Valley, located in southwestern Idaho, has been rapidly urbanizing; urban land cover has grown by 52% from 1985 to 2021. Understanding how land use and land cover changes …

Soil Carbon Storage And Its Relation To Abiotic And Biotic Factors In The Boise Foothills, Richie William Holder

Boise State University Theses and Dissertations

Terrestrial soil sequesters a significant amount of carbon (C), and changes to this pool can impact atmospheric CO2 concentrations and climate change. Thus, it is crucial to understand the drivers of the size of this pool. Changes in plant community composition in semi-arid ecosystems can impact soil C storage. However, little is known about the impact of plant functional type on the quantity and distribution of soil C on a landscape scale relevant to ecosystem management. I conducted a study in the City of Boise’s Open Space Reserves located north of Boise, Idaho to evaluate how plant functional type affects …

Unraveling Snow And Rain Contributions To Streamflow Through A Methodological Investigation On Cold And Warm Season End-Members, Rachel Grena

Boise State University Theses and Dissertations

Water supply and demand are encountering unique challenges in the western United States as climate change impacts the availability of water resources. Much of the west relies on high mountain snowpack to maintain consistent streamflow throughout the dry, warm season months. Temperatures often rise above freezing in the cold season, diminishing the snowpack size, and altering the timing of snowmelt. As droughts become more frequent, water managers are increasingly concerned about the risk of reduced summer streamflow. To understand changing hydrologic patterns, this study utilizes phase changes in precipitation, specifically the distinction between cold and warm season precipitation, and their …

Leveraging Weekly Snow Cover Time Series For Improved Glacier Monitoring And Modeling, Rainey Aberle, Ellyn M. Enderlin, David R. Rounce, Shad O'Neel, Brandon Tober, Alexandra Friel

Boise State University Publications and Presentations

Seasonal snow and ice melt strongly influence glacier mass balance, yet sparse sub-annual observations limit our understanding of seasonal dynamics. Here we construct and analyze weekly snow cover time series for 200 glaciers across western North America from 2013 to 2023 using an automated image processing pipeline. Snow cover varied widely across the region: snow minima timing varied with latitude — from August from 62 to 64N to October from 48 to 50N—and accumulation area ratios ranged from near-zero to 0.92 (median of 0.52). A comparison of snowlines from observations and the PyGEM glacier mass balance model revealed seasonally evolving …

Rectifying The Tephrostratigraphic Record Of The Pacific Northwest, Casey J. Crawford

Boise State University Theses and Dissertations

The Mid-Miocene Climatic Optimum (~17-14Ma) marks the last time that Earth’s atmospheric CO₂ concentrations were as high as modern levels, correlating to a peak of significant warming during an otherwise cooling trend through the Cenozoic. To understand how modern ecological systems may respond to CO₂ -induced climate change, paleontologists are studying how plant type and diversity changed with the rise and fall of CO₂ concentrations over the ~3Ma interval, and utilize intercalated tephras amenable to radioisotope geochronology to bracket fossiliferous horizons in time. The legacy model for tephrostratigraphy in the Pacific Northwest utilized Fe and Ca concentrations …

Improved Snow Distribution Estimates Using A Rapid-Response Lidar And Photogrammetry System, Naheem Idowu Adebisi

Boise State University Theses and Dissertations

Snow plays a critical role in global hydrology, climate systems, and human activities, particularly in mountainous regions where it is a primary source of freshwater, influences the energy balance, and impacts mobility and commerce. Despite its importance, accurately mapping and predicting snow distribution remains a major challenge due to the complex spatial and temporal variability of snowpack and the lack of an ideal observation system. This dissertation aims to advance our monitoring capability, understanding, and prediction capacity of snow distribution using Light Detection and Ranging (LiDAR) and photogrammetry techniques.

In chapter 2, I discussed the high-resolution LiDAR-derived datasets of multiple …

Effects Of Changing Winter Precipitation Phase On Streamflow Magnitude In Mountainous Regions, Josh Morell

Boise State University Theses and Dissertations

Snowmelt-produced streamflow (Q) is the dominant water source for a large portion of the global population. This is especially true in higher elevation regions in the Western United States. Precipitation is highly variable and seasonal in this region of the world. Generally, most precipitation occurs in winter and comes as snow in higher elevations. However, due to climate change, precipitation and temperature patterns are changing. It has been observed in many areas across the Western United States that the fraction of precipitation falling as snow (S_f) is declining because of a warming climate. In addition, …

Resilience Webtool: Engaging Community Partners To Humanize Data For Use In Local Resilience Planning In Valley County, Idaho, Sabrina Akther

Boise State University Theses and Dissertations

Advancements in technology have made hazard data increasingly available. However, officials in rural communities with limited resources often face challenges in accessing, interpreting, and applying these data to assess vulnerabilities and plan future development. Furthermore, when hazard data is not paired with relevant population and infrastructure, data vulnerability assessments become increasingly difficult. To address this challenge, this project aims to co-create a web tool with decision makers in Valley County, Idaho following a user-centered design approach, consolidating hazards, social vulnerability, and infrastructure data to help local officials with risk management, decision-making, and resilience planning. The project started with listening sessions, …

Tracking Natural Hazards: Bridging Rain-Triggered Lahar Research And Protective Action Decision Making In Wildland Fire Management, Ashley Bosa

Boise State University Theses and Dissertations

Understanding natural hazards is crucial for mitigating risks, protecting lives and property, and building resilience in communities. By enabling communities to prepare, respond effectively, and take protective action against disasters, the devastating impacts of natural hazards can be significantly reduced. However, transitioning from research to tangible community impact involves a multi-step process that bridges the gap between scientific knowledge and practical application. In this dissertation, I present two seismo-acoustic analyses of multiple rain-triggered lahar events at Volcán de Fuego in Guatemala, a granulometry study that attempts drone imagery analysis for lahar deposits, and a case-study review of the roles of …

Where And How Are Undergraduate Students Developing Dispositions Needed For The Geoscience Workforce?, Kaelyn Lagerwall

Boise State University Theses and Dissertations

Dispositions, such as the desire to learn, work ethic, initiative, and organization, are defined as internal attributes, attitudes, or values that stimulate action. Rather than being intrinsic traits, dispositions can be learned and are considered a dynamic and evolving arrangement of interconnected components. Dispositions are highly desired and valuable to the workforce, playing a critical role in gaining and maintaining employment; they are frequently mentioned in job advertisements for bachelor-level geoscientists. Therefore, it is important to understand where and how geoscience students are developing these dispositions as part of their degree programs. We surveyed faculty in geoscience departments at two …

From Classroom To Career: Preparing Future Geoscientists For Workforce Success, Gregory Shafer

Boise State University Theses and Dissertations

The wide range of career opportunities for geoscience students, combined with a changing workforce, makes it more challenging for undergraduate programs to adequately prepare students for their careers. Therefore, it is important for geoscience programs to have a comprehensive view of the workforce needs and what barriers students may encounter when transitioning to the workforce. This dissertation identifies key skills and competencies essential for bachelor-level geoscientists, as well as potential barriers for recent graduates entering the workforce. The study analyzed entry-level geoscience job advertisements using a case-insensitive code matching function in MATLAB and conducted interviews with geoscience employers to identify …

Palynostratigraphy And Bayesian Age Stratigraphic Model Of New Ca-Id-Tims Zircon Ages From The Walloon Coal Measures, Surat Basin, Australia, K. Sobczak, J. Cooling, T. Crossingham, H. G. Holl, M. Reilly, J. Esterle, J. L. Crowley, C. Hannaford, M. T. Mohr, Z. Hamerli, S. Hurter

Geosciences Faculty Publications and Presentations

The Surat Basin hosts significant coal and coal seam gas resources. New high-precision CA-TIMS U/Pb zircon ages from tuffs and Bayesian age stratigraphic models are combined with palynology from fine-grained sedimentary rocks and zircon trace elements to provide further chronostratigraphic and biostratigraphic constrains on the Walloon Coal Measures in the eastern margin of the Surat Basin and infer the palaeoenvironment and tectonic setting. The tuff ages range from 165.88 ± 0.11 Ma to 158.84 ± 0.05 Ma, with those from the stratigraphically lower Taroom Coal Measures ranging from 165.88 ± 0.11 to 163.05 ± 0.08 Ma and Juandah Coal Measures …

Radiogenic Isotope And Ionic Concentration Ratios Reveal Hydrologic Mixing, Subsurface Residence Time, And Cross-Basin Transfer In A Snow-Fed Mountain Karst Watershed, Nathaniel Ashmead

Boise State University Theses and Dissertations

Snow-fed karst aquifers support various complex ecosystems and provide a vital water source to communities worldwide. Due to their nature and distribution, these watersheds may be particularly vulnerable to the effects of climate change. Water resource managers can mitigate uncertainty from climate impacts with accurate predictions of future water availability provided by hydrologic models. While many such models exist, their effectiveness at predicting streamflow in snow-fed karst watersheds is limited by a lack of insight into the significance of cross-basin groundwater transfers. This study used radiogenic isotope and ionic concentration ratios as natural tracers to detect cross-basin transfer between two …

Using Raman Spectroscopy To Validate Metamorphic P-T Paths From Western New Hampshire, Alexis Thomas

Boise State University Theses and Dissertations

Constructing and interpreting pressure-temperature (P-T) paths in metamorphic rocks is crucial to understanding tectonic processes occurring at mid- to deep-crustal levels. Conventional methods for obtaining P-T paths rely on mineral chemistry, such as chemical zoning in garnets, which assumes growth at chemical equilibrium. However, studies show that garnet growth can occur with disequilibrium nucleation, which can result in a biased or potentially incorrect P-T path. An alternative, physics-based approach using Raman spectroscopy can also be used to determine P-T paths. This method involves using elastic thermobarometry of quartz inclusions within garnet. In this study, I tested the hypothesis that P-T …

Pre-Plinian Perplexity: Identifying And Constraining An Anomalous Pdc During The Initial Stages Of The May 18, 1980 Mt. St. Helens Eruption, Justin Crevier

Geosciences Undergraduate Theses

The Mount St. Helens (MSH) 18 May 1980 eruption was a formative event for a generation of volcanologists. With so much data available from detailed studies of the Blast and Plinian phases, MSH could aptly be called one of volcanology's greatest teachers—and the volcano may yet have more to teach us. The transition period, which occurred between the end of the Blast phase (0830) and the beginning of the Plinian phase (0920) on the morning of May 18, 1980, has not yet benefited from the same degree of comprehensive review as either of those phases. The conditions which caused the …

A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris Mccaslin, T. Dylan Mikesell, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Accurate knowledge of snow mechanical properties, including Young's modulus, shear modulus, Poisson's ratio, and density, is critical to many areas of snow science and to snow-related engineering problems. To facilitate the assessment of these properties, an innovative non-contacting laser ultrasound system (LUS) has been developed. This system acquires ultrasound waveform data at frequencies ranging from tens to hundreds of kHz in a controlled cold-lab environment. Two different LUS devices were compared in this study to determine which recorded more robust ultrasound in granular ice mix samples. We validated the ultrasound observations with poro-elastic traveltime modeling based on physical and empirical …

Climate And Channel Morphology Control Stream Drying Across Scales, Mac Beers

Boise State University Theses and Dissertations

Over half of the global stream network is estimated to dry for at least one day of the year. Streams that dry at some point in space and time are considered intermittent. Intermittent streams exhibit one of three hydrologic states: flowing, non-flowing pools, and dry. The distribution and extent of completely dry channel and non-flowing pools is important for water quality and ecology, however, we are currently unable to accurately predict when, where, and how streams dry at small scales. Few studies have investigated the stream characteristics that influence local scale controls of drying, and more work is needed to …

Improved Hydrologic Modeling And Geophysical Imaging Of Critical Zones: Incorporating Structural And Temporal Constraints, Hang Chen

Boise State University Theses and Dissertations

The Earth's critical zone (CZ) is a life-sustaining layer extending from the canopy of the tree to the bottom of the active groundwater circulation, providing valuable resources to terrestrial life, including nutrients, minerals, and fresh water. There are many challenges in studying various processes within and the function of the CZ. This dissertation addresses two common challenges in studying the CZ hydrology and watershed function, which are critical for a predictive understanding of the water dynamics in mountainous terrain and for an informed management of future water resources under rapid climate change. These challenges include (1) accurate quantification of hydrological …

Triggers Of Rapid Change In Glacier Dynamics, Jukes Liu

Boise State University Theses and Dissertations

The loss of land ice has become the greatest contributor to global mean sea level rise since 2006 (Oppenheimer et al., 2019). Glaciers have contributed ∼20% to global sea level rise over the last ∼2 decades (Oppenheimer et al., 2019; Hugonnet et al., 2021), while the ice sheets have contributed 33% (Oppenheimer et al., 2019). For the outlet glaciers and ice streams that drain the Greenland and Antarctic ice sheets, changes to their dynamics (flow speed, thickness, and length) dominate their present and future mass loss (King et al., 2020; Diener et al., 2021). One of the main limitations in …

Investigating The Distribution Of Soil Inorganic Carbon, And The Role Of Dust Deposition In Dryland Soils, Zahra Ghahremani

Boise State University Theses and Dissertations

The importance of dust deposition in the biogeochemical cycling of nutrients, sediment redistribution, and soil formation is well-known. Anthropogenic activities such as changing land use and agricultural practices can influence dust flux deposition rates, dust organic matter content, and the chemical composition of dust. This study examines the influence of agricultural activities on aeolian deposition in a the xeric intermontane westerns USA. We investigate seasonal and spatial variations in dust deposition rates, dust organic matter, dust inorganic matter, and dust geochemistry from passive dust traps. The Reynolds Creek Experimental Watershed (RCEW; Owyhee Mountains, Idaho) and the Northwest Irrigation and Soils …

Agricultural Irrigation Water Quality In The Lower Boise River Basin: A Quantitative Assessment Of Canal Ecosystem Metabolism And Escherichia Coli Spatiotemporal Variability, Reed Chasmar

Boise State University Theses and Dissertations

Irrigation canals are pervasive in agricultural landscapes. Despite their vast spatial extent and significant volumetric impact on the hydrologic cycle, the role of irrigation canals as intermittent channels within a river network, as well as their various functions (e.g., supporting aquatic ecosystems, transporting microbial communities, altering the carbon cycle), are not well understood. Microbial water quality and aquatic ecosystem metabolism represent two mechanisms to assess stream channels that can provide new insights into the complex dynamics and spatiotemporal patterns that exist in irrigation canals, which has relevance for both human health and for the field of stream ecology. The goal …

On The Use Of Elastic Waves To Study Snow Microstructure And Mechanical Properties: A Look From The Lenses Of Laser Ultrasound And Time-Lapse Seismic, J. Christopher Mccaslin

Boise State University Theses and Dissertations

Accurate knowledge of the mechanical and microstructural properties of snow is essential to improve snow science and engineering applications. In this dissertation, I investigated the use of ultrasound to quantify certain snow properties with a non-contacting laser ultrasound system (LUS), then I applied the knowledge gained from a small controlled lab-based method to a larger field-based active-source seismic method.

I first evaluated two different LUS devices to determine which one produced more accurate ultrasound observations in analog snow (i.e. shaved ice). The PSV-400 Scanning Vibrometer was found to provide higher quality ultrasound observations compared to the VibroFlex Fiber Vibrometer. Using …

A Cold Laboratory Hyperspectral Imaging System To Map Grain Size And Ice Layer Distributions In Firn Cores, Ian E. Mcdowell, Kaitlin M. Keegan, S. Mckenzie Skiles, Christopher P. Donahue, Erich C. Osterberg, Robert L. Hawley, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

The Greenland and Antarctic ice sheets are covered in a layer of porous firn. Knowledge of firn structure improves our understanding of ice sheet mass balance, supra- and englacial hydrology, and ice core paleoclimate records. While macroscale firn properties, such as firn density, are relatively easy to measure in the field or lab, more intensive measurements of microstructural properties are necessary to reduce uncertainty in remote sensing observations of mass balance, model meltwater infiltration, and constrain ice age – gas age differences in ice cores. Additionally, as the duration and extent of surface melting increases, refreezing meltwater will greatly alter …

Paleozoic Evolution Of The Yukon-Tanana Terrane Of The North American Cordillera, Nw British Columbia, R. Soucy La Roche, A. Zagorevski, N. L. Joyce, J. L. Crowley

Geosciences Faculty Publications and Presentations

The origins and primary relationships between tectono-stratigraphic units are fundamental to the terrane concept in accretionary orogens, but they are challenging to assess in metamorphic terranes. In NW British Columbia, three tectonically bounded metamorphic suites of the Yukon-Tanana terrane formed in distinct tectonic settings, based on high-spatial-resolution geochronology and immobile trace-element geochemistry. The Florence Range suite comprises late Neoproterozoic or younger to pre–latest Devonian metasedimentary rocks derived from continental crust, 360 ± 4 Ma calc-alkaline intermediate orthogneiss, and 357 ± 4 Ma amphibolite with oceanic-island basalt composition, consistent with rifting of a continental margin. The detrital signature is dominated by …

Influence Of Subsurface Critical Zone Structure On Hydrological Partitioning In Mountainous Headwater Catchments, Hang Chen, Qifei Niu, James P. Mcnamara, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Headwater catchments play a vital role in regional water supply and ecohydrology, and a quantitative understanding of the hydrological partitioning in these catchments is critically needed, particularly under a changing climate. Recent studies have highlighted the importance of subsurface critical zone (CZ) structure in modulating the partitioning of precipitation in mountainous catchments; however, few existing studies have explicitly taken into account the 3D subsurface CZ structure. In this study, we designed realistic synthetic catchment models based on seismic velocity-estimated 3D subsurface CZ structures. Integrated hydrologic modeling is then used to study the effects of the shape of the weathered bedrock …

High-Precision U-Pb Geochronology Links Magmatism In The Southwestern Laurentia Large Igneous Province And Midcontinent Rift, M. T. Mohr, M. D. Schmitz, N. L. Swanson-Hysell, K. E. Karlstrom, F. A. Macdonald, M. E. Holland, Y. Zhang, N. S. Anderson

Geosciences Faculty Publications and Presentations

The Southwestern Laurentia large igneous province (SWLLIP) comprises voluminous, widespread ca 1.1 Ga magmatism in the southwestern United States and northern Mexico. The timing and tempo of SWLLIP magmatism and its relationship to other late Mesoproterozoic igneous provinces have been unclear due to difficulties in dating mafic rocks at high precision. New precise U-Pb zircon dates for comagmatic felsic segregations within mafic rocks reveal distinct magmatic episodes at ca. 1098 Ma (represented by massive sills in Death Valley, California, the Grand Canyon, and central Arizona) and ca. 1083 Ma (represented by the Cardenas Basalts in the Grand Canyon and a …

Snow Water Equivalent Retrieval Over Idaho – Part 2: Using L-Band Uavsar Repeat-Pass Interferometry, Zachary Hoppinen, Shadi Oveisgharan, Hans-Peter Marshall, Ross Mower, Kelly Elder, Carrie Vuyovich

Geosciences Faculty Publications and Presentations

This study evaluates using interferometry on low-frequency synthetic aperture radar (SAR) images to monitor snow water equivalent (SWE) over seasonal and synoptic scales. We retrieved SWE changes from nine pairs of SAR images, mean 8 d temporal baseline, captured by an L-band aerial platform, NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), over central Idaho as part of the NASA SnowEx 2020 and 2021 campaigns. The retrieved SWE changes were compared against coincident in situ measurements (SNOTEL and snow pits from the SnowEx field campaign) and to 100 m gridded SnowModel modeled SWE changes. The comparison of in situ to …

Snow Water Equivalent Retrieval Over Idaho – Part 1: Using Sentinel-1 Repeat-Pass Interferometry, Shadi Oveisgharan, Robert Zinke, Zachary Hoppinen, Hans Peter Marshall

Geosciences Faculty Publications and Presentations

Snow water equivalent (SWE) is identified as the key element of the snowpack that impacts rivers' streamflow and water cycle. Both active and passive microwave remote sensing methods have been used to retrieve SWE, but there does not currently exist a SWE product that provides useful estimates in mountainous terrain. Active sensors provide higher-resolution observations, but the suitable radar frequencies and temporal repeat intervals have not been available until recently. Interferometric synthetic aperture radar (InSAR) has been shown to have the potential to estimate SWE change. In this study, we apply this technique to a long time series of 6 …

Geotechnical Characterisation Of Coal Spoil Piles Using High-Resolution Optical And Multispectral Data: A Machine Learning Approach, Sureka Thiruchittampalam, Bikram Pratap Banerjee, Nancy F. Glenn, Simit Raval

Geosciences Faculty Publications and Presentations

Geotechnical characterisation of spoil piles has traditionally relied on the expertise of field specialists, which can be both hazardous and time-consuming. Although unmanned aerial vehicles (UAV) show promise as a remote sensing tool in various applications; accurately segmenting and classifying very high-resolution remote sensing images of heterogeneous terrains, such as mining spoil piles with irregular morphologies, presents significant challenges. The proposed method adopts a robust approach that combines morphology-based segmentation, as well as spectral, textural, structural, and statistical feature extraction techniques to overcome the difficulties associated with spoil pile characterisation. Additionally, it incorporates minimum redundancy maximum relevance (mRMR) based feature …