Earth Sciences Commons^™

Geochemical Dynamics And Nitrous Oxide Release From The Hyporheic Zone Of Streams, Annika Marie Quick

Boise State University Theses and Dissertations

The hyporheic zones of streams and rivers, consisting of the sediments beneath and immediately adjacent to the stream channel, are an important site of geochemical processing. Due to the difficulty of measuring these geochemical processes in the hyporheic zone in situ with meaningful spatial and temporal resolution, we conducted multiple column and large-scale flume experiments to model 1D and 2D hyporheic flow paths and observed important geochemical reactions, including the production and consumption of nitrous oxide (N₂O). N₂O is a significant greenhouse gas, but the controls on its emissions from streams are poorly constrained. We describe …

Energizing North Dakota's Future, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Energy & Environmental Research Center’s 2018 goals for North Dakota’s natural resources and energy production. Goals include resource sustainability, eliminating pipeline leaks, and education. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Stratigraphic Reconstruction Of A Late Pleistocene Bald Cypress Forest Discovered On The Northern Gulf Of Mexico Continental Shelf, Suyapa Michell Gonzalez Rodriguez

LSU Master's Theses

A previously buried bald cypress forest (Taxodium distichum) was discovered on the continental shelf, offshore of Orange Beach, Alabama, USA, in ~20 m water depth. The forest was exhumed by Hurricane Ivan in 2004, and is now exposed as stumps in life position in a trough located in the northern Gulf of Mexico continental shelf seafloor. We are investigating the local stratigraphy, paleo-landscape, and mode of forest preservation of this unique site. In August 2015 and July 2016, submersible vibracores (18 in total) were collected. Core analysis included: bulk density and imaging via Geotek multi sensor core logger, …

Understanding The Late Mesoproterozoic Earth System From The Oldest Strata In Grand Canyon: C-Isotope Stratigraphy And Facies Analysis Of The 1254 Ma Bass Formation, Grand Canyon Supergroup, Az., Usa, Erin C. Lathrop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rocks provide insight into ancient times before complex animals existed. The oldest sedimentary rocks in Grand Canyon (the Bass Formation) allow us to glimpse into what things might have been like over a billion years ago. These rocks record the time known as the Mesoproterozoic Era (1.6 to 1.0 billion years ago), otherwise known as the ‘boring billion’. These rocks are thought to be the right age to indicate the end of an oddly stable world when continents were quiet and life was calm, yet they predate younger rocks that record extreme events. The Bass Formation, some of the only …

Spatial And Temporal Trends In Diet For Pinfish (Lagodon Rhomboides) From Turtle Grass (Thalassia Testudinum) Beds With Contrasting Environmental Regimes In The Lower Laguna Madre, Texas, Maximiliano Barbosa

Theses and Dissertations

Seagrass meadows in far South Texas are dominated by turtle grass (Thalassia testudinum), and juvenile pinfish (Lagodon rhomboides) are abundant grazers of seagrass epifauna. As they grow, pinfish exhibit an ontogenetic dietary shift and begin consuming increasing amounts of plant material. In this study, contrasting environmental regimes in two seagrass meadows were examined to identify how they might affect pinfish diets, diet shifts, and growth across the growing season. The eastern site was sheltered from prevailing southeasterly winds by a barrier island, while the western site was shallower and subjected to higher wind energy and turbidity. …

Structural Synthesis And Spatial Distribution Of A 335 Ma Igneous Suite From The Eastern Blue Ridge, Alabama Appalachians, Avery Rosenbalm

Honors Theses

The Appalachian range was formed by three orogenies, the most recent being the Alleghanian beginning at ~330 Ma. A small pluton outcropping along Highway 280 near Alexander City, AL, called the 280 granodiorite, has been dated at ~335 Ma and intrudes the Devonian Elkahatchee Quartz Diorite (EQD). While little work has been done on the intrusion, it is significant because of its age: all deformation of the intrusion should be related to the Alleghanian orogeny, while most other bodies in the region exhibit significant overprinting due to previous successive orogenies. The pluton was mapped constraining the geographic extent, which is …

Characteristics Of The Mantle Flow System Beneath The Indochina Peninsula Revealed By Teleseismic Shear Wave Splitting Analysis, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanh Phon Le, Jinyao Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Numerous geoscientific investigations have been conducted on the southeastern Tibetan Plateau and adjacent areas for understanding crustal and mantle deformation associated with the indentation of the Indian Plate into Eurasia. A number of key issues, such as the causes of a sudden change of fast polarization orientations from N-S to almost E-W at approximately 26°N revealed by shear wave splitting (SWS) studies, and the geodynamic implications of the transition still remain enigmatic, partially due to the lack of sufficient SWS measurements on the Indochina Peninsula. Here we employ the SWS technique to systematically illuminate upper mantle anisotropy beneath the Indochina …

Fossil Moles From The Gray Fossil Site, Tn: Implications For Diversification And Evolution Of North American Talpidae, Danielle Oberg

Electronic Theses and Dissertations

The Gray Fossil Site (GFS) is one of the richest Cenozoic terrestrial localities in the eastern United States. This study describes the first talpid specimens recovered from the GFS. Using measurements and comparisons of dental and humerus morphology, I identify 4 talpids (Parascalops nov. sp., Quyania cf. Q. europaea, Mioscalops (= Scalopoides) sp., and an unidentified stem desman) occurring at the GFS. Humeral morphology has been used to diagnose talpid species and study relationships. A geometric morphometric analysis showed that humerus shape is highly reflective of locomotor ecology in extant talpids and allows ecological inferences for fossil …

Postcranial Morphology And The Locomotor Adaptations Of Extant And Extinct Crocodylomorphs And Lepidosaurs, Laura Rooney

Electronic Theses and Dissertations

I have collected a series of linear measurements of the postcranial skeletons of 43 extant crocodylian and lepidosaur taxa to determine if those engaging in similar locomotor behavior display similar morphology despite phylogenetic differences. Stepwise discriminant function analyses reveal reptile locomotor mode can be accurately predicted (over 80% correct) based on morphology. Semi-aquatic taxa are distinguished by a longer ischium relative to pubis length, a longer scapula relative to humerus length, and a broader acetabulum than terrestrial and arboreal taxa. Arboreal taxa display a more elongate, gracile humerus and a smaller acetabulum. This morphometric data can potentially be used to …

Fm Radio Signal Propagation Evaluation And Creating Statistical Models For Signal Strength Prediction In Differing Topographic Environments, Timothy Land

Electronic Theses and Dissertations

Radio wave signal strength and associated propagation models are rarely analyzed across individual geographic provinces. This study evaluates the effectiveness of the Radio Mobile model to predict radio wave signal strength in the Blue Ridge and Valley and Ridge physiographic provinces. A spectrum analyzer was used on 19 FM transmitters to determine model accuracy. Statistical analysis determined the significance between different terrain factors and signal strength. Field signal strength was found to be related to test site elevation, transmitter azimuth, elevation angle, transmitter elevation, path loss, and distance. Using 76 signal strength receiver sites, Ordinary Least Square regression models predicted …

Geostatistical Analysis Of Potential Sinkhole Risk: Examining Spatial And Temporal Climate Relationships In Tennessee And Florida, Kimberly Blazzard

Electronic Theses and Dissertations

Sinkholes are a significant hazard for the southeastern United States. Although differences in climate are known to affect karst environments differently, quantitative analyses correlating sinkhole formation with climate variables is lacking. A temporal linear regression for Florida sinkholes and two modeled regressions for Tennessee sinkholes were produced: a general linearized logistic regression and a MaxEnt derived species distribution model. Temporal results showed highly significant correlations with precipitation, teleconnection patterns, temperature, and CO₂, while spatial results showed highly significant correlations with precipitation, wind speed, solar radiation, and maximum temperature. Regression results indicated that some sinkhole formation variability could be …

Analysis Of The Upper Cotton Valley Group In The Northeastern Mississippi Interior Salt Basin, Theresa A. Woehnker

Master's Theses

The Mississippi Interior Salt Basin (MISB) is a major negative structural feature in the interior onshore northeastern Gulf of Mexico. The Cotton Valley Group is an Upper Jurassic – Lower Cretaceous subsurface siliciclastic unit that has been studied extensively in the MISB for the last several decades because of its high potential as a reservoir rock. This study focuses on the Shuler Formation in the Upper Cotton Valley, which consists of an upper Dorcheat Member, and a lower Shongaloo Member. The boundary between these units correspond to a transgressive-regressive sequence boundary, which marks the beginning of a rise in sea …

Outbreak And Extinction Dynamics In Stochastic Populations, Garrett T. Nieddu

Theses, Dissertations and Culminating Projects

Each piece of work herein examines nonlinear population dynamics using methods from deterministic dynamical systems, stochastic processes and statistical mechanics. This dissertation is the compilation of three independent – but related – pieces of work: the first investigates an isolated population that is capable of maintaining multiple carrying capacities; the second project examines a stochastic Ebola model with a zoonotic disease reservoir; and the third looks at a basic disease-invasion model to characterize outbreak vulnerability and the connectedness of supposedly separate populations.

Each of these three chapters explore the interplay between interconnected systems, without explicitly modeling the elements that are …

The Role Of Co2 Sublimation In Mass Wasting And Landscape Evolution Under Martian Conditions, Matthew Edwin Sylvest

Graduate Theses and Dissertations

Here we present the first set of laboratory experiments under martian atmospheric conditions which demonstrate that the sublimation of CO2 ice from within the sediment body can trigger failure of unconsolidated, regolith slopes, and can measurably alter the landscape. Previous theoretical studies required CO2 slab ice for movements, but we find that only frost is required. Hence, sediment transport by CO2 sublimation could be more widely applicable (in space and time) on Mars than previously thought. This supports recent work suggesting CO2 sublimation could be responsible for recent modification in martian gullies.

A second set of experiments were carried out …

Gis Modeling Of The Prominent Geohazards In Arkansas, Kyle Walker Rowden

Graduate Theses and Dissertations

The State of Arkansas is prone to numerous geohazards. This thesis is a twofold study of prominent geohazards in Arkansas: the first fold includes a novel triggerless approach for mass wasting susceptibility modeling applied to the Boston Mountains in NW Arkansas, and the second fold is a GIS-based regression modeling of the extreme weather patterns at the state level. Each study fold is presented in this thesis as a separate chapter embracing a published peer-reviewed paper. In the first paper, I have used the analytical hierarchy process to assign preliminary statistical weights to the most cogent variables influencing mass wasting …

Structural Geology Of The Caddo Gap Area, Ouachita Mountains, Arkansas, Martin Messmer

Electronic Theses and Dissertations

The Caddo Gap quadrangle is located on the southern margin of the Benton Uplift, the orogenic core of the Ouachita Mountains. Recent field mapping focused on delineating stratigraphic and structural relationships in the southern part of the quadrangle to improve existing reconnaissance-scale maps of the area. New structures were discovered that provide further information about the structural evolution of the Ouachita fold and thrust belt.

Field work included mapping the three informal members (Lower, Middle and Upper) of the Arkansas Novaculite. Major folds within the study area include the Nelson Mountain Anticline and two synclinal folds (“South Caddo Mountain” and …

Extraction Of Metazoan Meiofauna From Muddy Deep-Sea Samples: Operator And Taxon Effects On Efficiency, Melissa Rohal, David Thistle, Erin E. Easton

School of Earth, Environmental, & Marine Sciences Faculty Publications

Deep-sea metazoan meiofaunal specimens are usually extracted from muddy samples by centrifugation in a fluid in which meiofauna tend to float and sediment particles tend to sink. Although the procedure is in common use, its efficiency has seldom been examined. The study reported here showed that well-trained operators extracted metazoan meiofauna with efficiencies that were different enough to be a concern in quantitative studies. Therefore, samples should be assigned to operators in a stratified-random manner. In the course of these studies, both operators also extracted individuals of the common nematode family Desmoscolecidae significantly less efficiently than other nematode families, a …

Sequence Stratigraphy, Chemostratigraphy And Facies Analysis Of Cambrian Series 2 - Series 3 Boundary Strata In Northwestern Scotland, Luke E. Faggetter, Paul B. Wignall, Sara B. Pruss, Yadong Sun, Robert J. Raine, Robert J. Newton, Mike Widdowson, Michael M. Joachimski, Paul M. Smith

Geosciences: Faculty Publications

Globally, the Series 2 - Series 3 boundary of the Cambrian System coincides with a major carbon isotope excursion, sea-level changes and trilobite extinctions. Here we examine the sedimentology, sequence stratigraphy and carbon isotope record of this interval in the Cambrian strata (Durness Group) of NW Scotland. Carbonate carbon isotope data from the lower part of the Durness Group (Ghrudaidh Formation) show that the shallow-marine, Laurentian margin carbonates record two linked sea-level and carbon isotopic events. Whilst the carbon isotope excursions are not as pronounced as those expressed elsewhere, correlation with global records (Sauk I - Sauk II boundary and …

Interpretation And Fracture Characterization Of Early-Cretaceous Buda Limestone Formation Using Post-Stack 3d Seismic Data In Zavala County, Texas, Andrey Smirnov

Graduate Theses and Dissertations

The Buda Limestone is a naturally fractured Early Cretaceous carbonate formation in south Texas which unconformably underlies the Eagle Ford Shale. Matrix porosity of the Buda is less than 6%, therefore natural fractures improve the potential for commercial hydrocarbon production from this tight limestone formation. This presents a challenge for producers to identify these zones using well log and post stack 3D seismic data typically available to medium or small exploration companies. This project provides a workflow based on well log analysis tied to seismic acoustic impedance (AI) inversion to locate areas of probable natural fractures. Acoustic impedance inversion was …

Soil Properties That Influence The Occurrence Of Hydrogen Sulfide Toxicity In Rice Fields, Julia Marie Fryer

Graduate Theses and Dissertations

Rice (Oryza sativa L.) producers face many challenges throughout each growing season. Hydrogen sulfide (H2S) toxicity is a physiological disorder where sulfate (SO42-) is excessively reduced to the toxic gas, H2S. This can reduce yield and, in severe cases, result in crop death. The main research objectives were to: i) understand chemical and physical characteristics in soils prone to H2S toxicity, ii) determine influential soil characteristics on the incidence of H2S toxicity, iii) determine ammonium sulfate ((NH4)2SO4) fertilizer additions influence on H2S toxicity, and iv) predict when and where H2S will occur. Three greenhouse experiments were conducted using Arkansas field …

Nitrous Oxide Emissions From Rice Production On A Silt-Loam Soil In Arkansas, Casey Rector

Graduate Theses and Dissertations

Rice (Oryza sativa L.) is a common crop grown in Arkansas under flooded-soil conditions. The saturated to nearly saturated soil makes rice production an ideal environment for the production of potent greenhouse gases, such as nitrous oxide (N2O). The objectives of this study were to i) evaluate the impact of water management practice (full-season-flood and intermittent-flood) and cultivar (pure-line and hybrid) on N2O fluxes, season-long N2O emissions, and global warming potential (GWP; 2016) and ii) evaluate the impact of tillage practice [conventional tillage and no-tillage (NT)] and type of urea fertilizer [ N-(n-butyl) thiosphosphoric triamide (NBPT)-coated and non-coated urea] on …

Structural Cross Sections And Subsurface Maps Of The Atoka Formation In The Northern Arkoma Basin, Western And Northwestern Arkansas, David Nance

Graduate Theses and Dissertations

The Arkoma Basin is one of several peripheral foreland basins situated on the front of the Ouachita orogenic fold and thrust belt. The transition from the foredeep to the Ozark Plateaus is a short one in terms of latitude. The Atoka Formation in Arkansas comprises the bulk of the sediments in the Arkoma Basin. Three divisions of the Atoka Formation have been informally assigned as the Upper, Middle, and Lower based on differences in sedimentary response to tectonic processes that occurred during the formation and subsidence of the Arkoma Basin. In the Arkansas portion of the Arkoma Basin, the lower …

Applications Of Reservoir Limnology Theory And Steady-State Modeling To Eutrophication Management In Beaver Lake, Arkansas, Matthew Rich

Graduate Theses and Dissertations

Reservoir limnology theory predicts that phytoplankton biomass (PB) is greatest in riverine-transition zones and least in lacustrine zones leading to an inverse pattern in water clarity. These theoretical patterns were utilized to create a statistical model of chlorophyll-a (Chl-a), an indicator of PB, and Secchi transparency (ST), an indicator of Chl-a, in Beaver Lake, Arkansas, a 12,800-ha reservoir, in order to hindcast historical conditions. Sampling for Chl-a, ST, and photic depth occurred semimonthly at 12 locations along a 78-km transect from the river inflow to the dam during the 2015 growing season. The ratio of Chl-a and ST measured at …

New Geochemical And Isotopic Approaches To Shallow Crust Landform Evolution, David Decker

Earth and Planetary Sciences ETDs

Many researchers have studied the Guadalupe Mountains in detail and starting with King (1948), many of them have speculated about the timing of the uplift of the Guadalupe block. There are several competing hypotheses including Laramide, Basin and Range, and Rio Grande Rifting uplift scenarios. Using uranium-lead dating of scalenohedral spar found in small vug caves throughout the study area, I have dated the episodes of spar formation to two major phases, 36 to 33 Ma and 30 to 27 Ma. These two episodes of spar formation are in good agreement with the time frame of the ignimbrite flare up …

Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood

Graduate Theses/Dissertations

Springfield, MO is located on the Springfield Plateau physiographic province. The Springfield plateau contains a number of Mississippian aged units and is mainly capped by the Burlington-Keokuk Formation. The Burlington-Keokuk is a highly fossiliferous limestone with nodular and interbedded chert. Beneath the Burlington-Keokuk lies the Elsey, Reeds Spring, and Pierson Formations respectively which comprise the Springfield Plateau aquifer hydrostratigraphic unit. Within the Springfield Plateau aquifer, a well-developed karst system includes springs, sinkholes, and caves. The Springfield Plateau aquifer is the predominant source for springs and seeps in the Springfield area. The purpose of this study was to understand the differences …

Geology Of The Purgatory Saddle 7.5 Minute Quadrangle, And Gravity And Magnetic Analysis Of Accreted Terrane Boundary, Western Idaho, Sourav Krishna Nandi

Graduate Theses/Dissertations

Western Idaho (USA) contains deformation associated with the Mesozoic accretion of volcanic island arc terranes of the Blue Mountains Province to Laurentia. The near vertical boundary between the accretionary orogeny and Precambrian North America is represented by the transpressional western Idaho shear zone, which lies east of metamorphic rocks in the Salmon River suture zone. The Blue Mountains Province in western Idaho contains four accreted crustal blocks: the Wallowa, Olds Ferry, Baker, and Izee terranes. The purpose of this study is to understand the structural relationship of the pre-accretionary, syn-accretionary and post-accretionary tectonic features along the accreted terrane boundary in …

Crustal Structure Of The Bhutanese Himalaya: New Insights From A Gravity Analysis In Western And Central Bhutan, Kinzang Duba

Graduate Theses/Dissertations

To expand the current understanding of lithospheric structure within Bhutan Himalaya, a detailed gravity survey was conducted for the first time along the all major roads within western and central Bhutan in 2015-2017. The acquired Bouguer gravity anomaly data were analyzed and interpreted using map methods (wavelength filtering and Euler deconvolution) which clearly indicate that there are substantial anomalies due to crustal density sources and a complex Himalayan geology. Four two-dimensional gravity models across the Himalayan tectonostratigraphic units were constructed to determine the crustal density structure using constraints from the geological and geophysical studies. The results support that the long …

Regional Stratigraphy And Distribution Of The Coastal Group, St. Elizabeth Parish, Southwestern Jamaica, Brett M. Kenning

Graduate Theses/Dissertations

This contribution examines the characteristics and ages of sedimentary units in the Coastal Group located along the southwestern Jamaica coast between Great Pedro Bluff and Fort Charles Bay in southwestern St. Elizabeth Parish. The coastline is characterized by laterally discontinuous low cliff exposures, separated by modern beach deposits and tectonically raised shore platforms composed of the White Limestone Group (mid-Eocene to mid-Miocene) and coral rudstone to floatstone and calcareous sandstone of the Coastal Group (late Pleistocene). Electron-Spin Resonance spectroscopy conducted on corals collected from a coral rudstone to floatstone facies yielded an estimated age of 120 ka. The coral facies …

Advancing The Understanding Of Environmental Transformations, Bioavailability And Effects Of Nanomaterials, An International Us Environmental Protection Agency—Uk Environmental Nanoscience Initiative Joint Program, Mitch M. Lasat, Kian Fan Chung, Jamie Lead, Steve Mcgrath, Richard J. Owen, Sophie Rocks, Jason M. Unrine, Junfeng Zhang

Plant and Soil Sciences Faculty Publications

Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United …

Building Up Biogeography: Pattern To Process, William D. Pearse, A. Marcia Barbosa, Susanne A. Fritz, Sally A. Keith, Luke J. Harmon, John Harte, Daniele Silvestro, Xiao Xiao, T. Jonathan Davies

Ecology Center Publications

Linking pattern to process across spatial and temporal scales has been a key goal of the field of biogeography. In January 2017, the 8th biennial conference of the International Biogeography Society sponsored a symposium on Building up biogeography—process to pattern that aimed to review progress towards this goal. Here we present a summary of the symposium, in which we identified promising areas of current research and suggested future research directions. We focus on (1) emerging types of data such as behavioral observations and ancient DNA, (2) how to better incorporate historical data (such as fossils) to move beyond what we …