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Full-Text Articles in Earth Sciences

Mgrre_Lithstriplog_R. 1 & R. 24_21101000140000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_R. 1 & R. 24_21101000140000, Mgrre Western Michigan University

Legacy Color Lithology Strip Logs

No abstract provided.


Mgrre_Lithstriplog_Schoonmaker, Lillian M 1_21107206400000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Schoonmaker, Lillian M 1_21107206400000, Mgrre Western Michigan University

Legacy Color Lithology Strip Logs

No abstract provided.


Mgrre_Lithstriplog_Jacobs, Mary 1_21111023820000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Jacobs, Mary 1_21111023820000, Mgrre Western Michigan University

Legacy Color Lithology Strip Logs

No abstract provided.


Mgrre_Lithstriplog_H.E. Tope Inc. A-1_21073277750000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_H.E. Tope Inc. A-1_21073277750000, Mgrre Western Michigan University

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No abstract provided.


Mgrre_Lithstriplog_Emery Brothers 1_21069004579000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Emery Brothers 1_21069004579000, Mgrre Western Michigan University

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No abstract provided.


Mgrre_Lithstriplog_Emery, Sadie 1_21057166640000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Emery, Sadie 1_21057166640000, Mgrre Western Michigan University

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No abstract provided.


Mgrre_Lithstriplog_Bridgman Oil And Gas 1_21021003689000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Bridgman Oil And Gas 1_21021003689000, Mgrre Western Michigan University

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No abstract provided.


Mgrre_Lithstriplog_State Grant 1_21107103240000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_State Grant 1_21107103240000, Mgrre Western Michigan University

Legacy Color Lithology Strip Logs

No abstract provided.


Mgrre_Lithstriplog_Fike, Vernell 2_21073272510000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Fike, Vernell 2_21073272510000, Mgrre Western Michigan University

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No abstract provided.


Mgrre_Lithstriplog_Packaging Corp Of America Unit "C" 1-26_21101304270000, Mgrre Western Michigan University May 2022

Mgrre_Lithstriplog_Packaging Corp Of America Unit "C" 1-26_21101304270000, Mgrre Western Michigan University

Legacy Color Lithology Strip Logs

No abstract provided.


Murphy Scale: A Locational Equivalent Intensity Scale For Hazard Events, Yi Victor Wang, Antonia Sebastian May 2022

Murphy Scale: A Locational Equivalent Intensity Scale For Hazard Events, Yi Victor Wang, Antonia Sebastian

Institute for ECHO Articles and Research

Empirical cross-hazard analysis and prediction of disaster vulnerability, resilience, and risk requires a common metric of hazard strengths across hazard types. In this paper, the authors propose an equivalent intensity scale for cross-hazard evaluation of hazard strengths of events for entire durations at locations. The proposed scale is called the Murphy Scale, after Professor Colleen Murphy. A systematic review and typology of hazard strength metrics is presented to facilitate the delineation of the defining dimensions of the proposed scale. An empirical methodology is introduced to derive equivalent intensities of hazard events on a Murphy Scale. Using historical data on …


Trace Metal Speciation And Impacts On Iron Oxide Transformations And Biogeochemical Cycling, Jinshu Yan May 2022

Trace Metal Speciation And Impacts On Iron Oxide Transformations And Biogeochemical Cycling, Jinshu Yan

Arts & Sciences Graduate Student Theses and Dissertations

Trace metals in anoxic aquatic systems are of great importance for iron oxide transformations and biogeochemical cycling. The presence of trace metal can alter iron oxide transformations under anoxic conditions. Trace metals are also essential for microbially-mediated biogeochemical processes occurring in anoxic wetland soils and stream bed sediments, but low availability of these elements may inhibit anaerobic element cycling and transformations. Trace metal speciation is also vital for understanding the environmental control on nutrients and contaminants. Three projects were conducted to explore trace metal speciation and its associated effect on iron oxide transformations and biogeochemical cycling. First, the Fe(II)-promoted conversion …


Subsurface Geophysical Investigations Of Oneida Lake Ny: Insights Into Ice Sheet Processes And Deglaciation At Termination I, Nicholas John Zaremba May 2022

Subsurface Geophysical Investigations Of Oneida Lake Ny: Insights Into Ice Sheet Processes And Deglaciation At Termination I, Nicholas John Zaremba

Dissertations - ALL

Reconstructing the retreat of the Laurentide Ice Sheet (LIS) provides insight into understanding end-Pleistocene climate, a critical set of boundary conditions prior to the onset of Holocene climates that were optimal for human dispersal and societal growth. Constraining ice sheet dynamics, glacier retreat rates, and the timing of still-stands and readvances requires identifying glacial landforms such as moraines, drumlins, and mega-scale glacial lineations (MSGLs). Drumlins and MSGLs indicate ice sheet flow directions and provide the location of paleo-ice streams, which were accelerated and localized pathways for ice discharge. Ice streams control ice sheet mass balance; therefore, identifying the location of …


Stable Carbon And Nitrogen Isotopes Of Shell Bound Organic Matter, Implications For Modern And Ancient Food Web Dynamics, Shibajyoti Das May 2022

Stable Carbon And Nitrogen Isotopes Of Shell Bound Organic Matter, Implications For Modern And Ancient Food Web Dynamics, Shibajyoti Das

Dissertations - ALL

Stable isotopes are an important tool for solving biogeochemical problems and have been increasingly applied in ecosystem studies because of their utility as source-to-sink tracers and for ecological information. Elements like C and N have more than one stable isotope, and their isotopic compositions (δ15N and δ13C) vary in a foreseeable way and are specifically useful in studying global elemental cycles and energy flow through ecosystems. δ15N and δ13C of organic matter (OM) are diagnostic of an organism's diet and have been used as a proxy for trophic level reconstructions. However, because of several analytical constraints, the use of stable …


Low-Temperature Plasticity Of Rock-Forming Minerals, Michael Keith Sly May 2022

Low-Temperature Plasticity Of Rock-Forming Minerals, Michael Keith Sly

Arts & Sciences Graduate Student Theses and Dissertations

The rheology of the Earth’s crust and mantle is in part governed by the physical and mechanical properties of feldspar, quartz, calcite, and olivine. Over the past several decades a significant number of experimental studies have been performed on these minerals. Conventional experiments are generally performed at elevated temperatures because much of the viscoplastic deformation of these minerals is accommodated by high-temperature mechanisms. There is, however, evidence of viscoplastic deformation at lower temperatures (T ≤ 0.3Tm) in the uppermost mantle and throughout the crust. Micromechanical experimental techniques, including nanoindentation and micropillar deformation, can be used to achieve plastic deformation at …


Nutrient Restoration Of A Large, Impounded, Ultra-Oligotrophic Western River To Recover Declining Native Fishes, Ryan S. Hardy, Tyler J. Ross, Kevin N. Mcdonnell, Michael C. Quist, Charlie Holderman, Bryan S. Stevens May 2022

Nutrient Restoration Of A Large, Impounded, Ultra-Oligotrophic Western River To Recover Declining Native Fishes, Ryan S. Hardy, Tyler J. Ross, Kevin N. Mcdonnell, Michael C. Quist, Charlie Holderman, Bryan S. Stevens

United States Geological Survey: Staff Publications

Declines in many fish populations in large, western rivers have been primarily attributed to the anthropogenic reduction of nutrient inputs and subsequent impacts to the food web. The largest known river fertilization program was implemented starting in 2005 on the Kootenai River in northern Idaho to restore resident fisheries. Annual electrofishing surveys were conducted at multiple sites in Idaho and Montana before and during nutrient addition to evaluate assemblage and population-level responses. Although few responses in fish assemblage structure were observed, the addition of liquid ammonium polyphosphate fertilizer (3 μg/L) to the Kootenai River increased fish abundance and biomass over …


An Interdisciplinary Approach To Understanding Volcanoes And Their Processes, Katherine Cosburn May 2022

An Interdisciplinary Approach To Understanding Volcanoes And Their Processes, Katherine Cosburn

Physics & Astronomy ETDs

To better understand volcanoes and their processes is important from both a fundamental science perspective and for hazard monitoring purposes. The complexity and limitations we face in pursuing such a science are numerous and this dissertation explores how an interdisciplinary approach combining physics, computer science, and volcanology can address this complexity in a straightforward and meaningful way. This is achieved through various modelling techniques across three studies: (1) a first-order analytic modelling of stratovolcano topographic shape, (2) the use of a Bayesian joint inversion on gravity and novel cosmic-ray muon measurements for imaging flat-lying subsurface density anomalies, and (3) the …


Structural And Biological Analysis Of Faults In Basalts In Sheepshead Mountains, Oregon As An Earth Analogue To Mars, Allison Bohanon May 2022

Structural And Biological Analysis Of Faults In Basalts In Sheepshead Mountains, Oregon As An Earth Analogue To Mars, Allison Bohanon

Theses and Dissertations

Microbial life on Mars is not visible from orbit or by rover cameras, but the fracture networks and scarp morphologies associated with fractures they could live in are measurable. We conducted a field analogue study of 92 normal fault scarps in the Sheepshead Mountains, Oregon to examine the correlation between scarp morphology and vegetation growth in the Steens Basalt. While vegetation is not expected on Mars, the fracture networks that sustain vegetation offer the same micro-environment that would support and protect endoliths. Structural variables were measured in the field and infrared spectra of fault scarps were measured using a handheld …


Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju May 2022

Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju

Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis …


Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates May 2022

Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates

Theses and Dissertations

Methods of forecasting streamflow using atmospheric ensembles and hydrologic routing have greatly improved over the past decades. These forecasts anticipate the timing and magnitude of streamflow peaks, enabling early warning of floods. Recent advances in atmospheric modeling have enabled production of forecasts months ahead, which are less precise but give a useful sense of trends.

The purpose of this study is to produce and evaluate a seasonal streamflow forecast model using a Muskingum routing hydrologic model coupled with runoff from a land surface model, and atmospheric input from a medium-term atmospheric and precipitation model. To evaluate the skill of the …


Characterization Of Quaternary Stratigraphy In The Mississippi Sound To Evaluate The Influence Of Geologic Heterogeneity On Submarine Groundwater Transport And Discharge, Zachary Peoples May 2022

Characterization Of Quaternary Stratigraphy In The Mississippi Sound To Evaluate The Influence Of Geologic Heterogeneity On Submarine Groundwater Transport And Discharge, Zachary Peoples

Theses and Dissertations

Submarine Groundwater Discharge (SGD) through seafloor sediments is gaining recognition as an important component of coastal water quality. Stratigraphic features creating geologic heterogeneity, such as incised paleochannels, may influence preferential pathways for SGD. The central Mississippi Sound is underlain by paleochannels that were incised into Pleistocene sediments while the area was subaerially exposed during the last glacial maximum and are now buried by transgressive Holocene deposits. In this thesis, newly collected chirp, previously published seismic reflection, and sediment core data are used to characterize the three-dimensional structure of the Holocene-Pleistocene contact. Results indicate that Pleistocene paleochannels cross-cut the study area, …


A New Model For Predicting The Drag And Lift Forces Of Turbulent Newtonian Flow On Arbitrarily Shaped Shells On The Seafloor, Carley R. Walker, James V. Lambers, Julian Simeonov May 2022

A New Model For Predicting The Drag And Lift Forces Of Turbulent Newtonian Flow On Arbitrarily Shaped Shells On The Seafloor, Carley R. Walker, James V. Lambers, Julian Simeonov

Dissertations

Currently, all forecasts of currents, waves, and seafloor evolution are limited by a lack of fundamental knowledge and the parameterization of small-scale processes at the seafloor-ocean interface. Commonly used Euler-Lagrange models for sediment transport require parameterizations of the drag and lift forces acting on the particles. However, current parameterizations for these forces only work for spherical particles. In this dissertation we propose a new method for predicting the drag and lift forces on arbitrarily shaped objects at arbitrary orientations with respect to the direction of flow that will ultimately provide models for predicting the sediment sorting processes that lead to …


Analysis Of Fossil Pollen From A Pleistocene Cypress Forest Preserved On The Northern Gulf Of Mexico Continental Shelf, Kathryn Joyce Garretson May 2022

Analysis Of Fossil Pollen From A Pleistocene Cypress Forest Preserved On The Northern Gulf Of Mexico Continental Shelf, Kathryn Joyce Garretson

Master's Theses

This study presents the findings of fossil pollen analysis performed on terrestrial sediments preserved on the northern Gulf of Mexico continental shelf (site hereafter known as the Underwater Forest or DF). This research aims to establish vegetation composition on a continental shelf glacial refuge and provide a better understanding of vegetation response to sea-level rise. Two cores (15DF1 and 15DF3B) located at different locations within the forest were recovered and analyzed. Pollen results from both cores were similar, with high percentages of Taxodium and Nyssa pollen in the lowermost sections reflecting an assemblage typical of contemporary baldcypress swamps. Pollen assemblages …


Using Geologic Principles And Data To Create A Symphony For Wind Ensemble, Thomas J. Davis May 2022

Using Geologic Principles And Data To Create A Symphony For Wind Ensemble, Thomas J. Davis

2022 Symposium

Geology and geologic processes have featured in many pieces of classical music such as Alan Hovhaness’ symphonic works after Mt. St. Helens and Glacier Peak but these pieces are impressionistic and only take general inspiration from the geology of their subjects. This paper describes the creation of Tectonics (2021) a piece which incorporates and describes many geologic principles and processes, such as mantle convection, through the musical form of cannon, the formation of fold and thrust belts whose cross sections are directly visually recreated in the score, and the physical dynamics of earthquake waves demonstrated through variations of pitch and …


Reconstructing The Ecological Relationships Of Late Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced These Relationships, Ian D. Broxson May 2022

Reconstructing The Ecological Relationships Of Late Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced These Relationships, Ian D. Broxson

2022 Symposium

The Sandwich Bluff Formation of the James Ross Basin of Antarctica has recently yielded a group of five late Cretaceous dinosaurs that lived contemporaneously with each other, a first for Antarctica. These five dinosaurs include fragmentary remains of two differently sized elasmarian ornithopods, a possible megaraptor, a hadrosaur, and a nodosaur. In this study we will construct a model of the ecological relationships of late Cretaceous Antarctica. Additionally, we will look at what specific factors allowed this group of four herbivores and a carnivore to coexist in a restricted locality and what niches were filled by each species. Methods to …


Pre-Eruptive Magma Configurations And Petrogenetic Relationships Of The Rattlesnake Tuff, Oregon–Insights From Spectacularly Banded High-Silica Rhyolite Pumices, Vanessa M. Swenton, Martin J. Streck May 2022

Pre-Eruptive Magma Configurations And Petrogenetic Relationships Of The Rattlesnake Tuff, Oregon–Insights From Spectacularly Banded High-Silica Rhyolite Pumices, Vanessa M. Swenton, Martin J. Streck

Geology Faculty Publications and Presentations

The 7.1Ma Rattlesnake Tuff (RST) of eastern Oregon is a widespread and voluminous (>300 km3) ignimbrite composed of 99% crystal poor (≤1%) high-silica rhyolite (HSR) and


Age And Water-Quality Characteristics Of Groundwater Discharge To The South Loup River, Nebraska, 2019, Christopher M. Hobza, John E. Solder May 2022

Age And Water-Quality Characteristics Of Groundwater Discharge To The South Loup River, Nebraska, 2019, Christopher M. Hobza, John E. Solder

United States Geological Survey: Water Reports and Publications

Streams in the Loup River Basin are sensitive to groundwater withdrawals because of the close hydrologic connection between groundwater and surface water. The U.S. Geological Survey, in cooperation with the Upper Loup and Lower Loup Natural Resources Districts, and the Nebraska Environmental Trust, studied the age and water-quality characteristics of groundwater near the South Loup River to assess the possible effects of a multiyear drought on streamflow.

Groundwater sampled in wells screened in Quaternary-age deposits displayed a wide range of mean ages (27 to 2,100 years), fraction modern, and susceptibility index values. Groundwater with higher concentrations of chloride and higher …


Ontogenetic Niche Shift As A Driver Of Community Structure And Diversity In Non-Avian Dinosaurs, Katlin M. Schroeder May 2022

Ontogenetic Niche Shift As A Driver Of Community Structure And Diversity In Non-Avian Dinosaurs, Katlin M. Schroeder

Biology ETDs

As some of the most charismatic megafauna to ever walk the earth, the physiology, morphology, growth and evolution of non-avian theropods has been studied exhaustively, yet little is understood about their roles in ecosystems as juveniles. For carnivorous megatheropods, which exceed 1,000kg in mass yet hatched from eggs of limited size, the likelihood of utilizing different prey through ontogeny was high, simply by proxy of the immense difference in size between adults and juveniles. We found these ontogenetic niche shifts, evidenced by significantly different dental microwear in Tyrannosaurids, to have excluded dinosaurian mesocarnivores from Mesozoic communities. The few dinosaurian mesocarnivores …


The Current State Of Community Engagement In Urban Soil Pollution Science, Nicole Fernández-Viña, Yujuan Chen, Kirsten Schwarz May 2022

The Current State Of Community Engagement In Urban Soil Pollution Science, Nicole Fernández-Viña, Yujuan Chen, Kirsten Schwarz

Agricultural and Environmental Sciences Faculty Research

Environmental burdens disproportionately impact the health of communities of color and low-income communities. Contemporary and legacy industry and land development may pollute soils with pesticides, petroleum products, and trace metals that can directly and indirectly impact the health of frontline communities. Past efforts to study environmental injustice have often excluded those most impacted, created distrust of researchers and other experts among frontline communities, and resulted in little to no structural change. Prevailing research methods value formal knowledge systems, while often dismissing the knowledge of those most harmed by environmental hazards. Community science has emerged as a process of doing science …


A Method For Phenotyping Roots Of Large Plants, Brian Rinehart, Hanna J. Poffenbarger, Daniel Lau, David H. Mcnear May 2022

A Method For Phenotyping Roots Of Large Plants, Brian Rinehart, Hanna J. Poffenbarger, Daniel Lau, David H. Mcnear

Plant and Soil Sciences Faculty Publications

Linking root traits to plant functions can enable crop improvement for yield and ecosystem functions. However, plant breeding efforts targeting belowground traits are limited by appropriate phenotyping methods for large root systems. While advances have been made allowing for imaging large in situ root systems, many of these methods are inaccessible due to expensive technology requirements. The aim of this work was to develop a plant phenotyping platform and analysis method suitable for assessing root traits of large, intact root systems. With the use of a purpose-built imaging table and automated photo capture system, machine learning-based image segmentation, and off-the-shelf …