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Paleoecological Analysis Of The Clayton Formation (Paleocene) Near Malvern, Arkansas, Brenna J. Hart

Honors Theses

The Clayton Formation is a section of the Midway Group immediately above the Cretaceous-Paleogene boundary that contains marine fossils from the Paleocene Epoch. The formation is composed of glauconitic sand, clay, marl, and limestone. Fossils within the formation commonly occur in clay or are concentrated in conglomeratic lag lenses. To assess paleoecology of the region during the Paleocene, the Clayton Formation was sampled for fossil content at a distinctly visible exposure along Interstate 30 near Malvern, Arkansas, that was excavated as part of a landslide mitigation project. Complimentary sites were sampled nearby along the Ouachita River and behind a shopping …

Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey

Graduate Theses and Dissertations

The dynamics of channel mouth bifurcations on river deltas can be understood using theory developed in tributary channel networks. Bifurcations in groundwater-fed tributary networks have been shown to evolve dependent on diffusive ground water flow patterns

directly adjacent to the channel network, producing a critical angle of 72°. We test the hypothesis that bifurcation angles in distributary channel networks are likewise dictated by a diffusive external flow field, in this case the shallow surface water surrounding the subaqueous portion of distributary channels in a deltaic setting. We measured 25 unique distributary bifurcations in an experimental delta and 197 bifurcations in …

Using Cross-Sets For Paleodischarge Estimation And Paleocurrent Vectors In The Parthenon Sandstone, Northwest Arkansas, Sean Robert Parry

Graduate Theses and Dissertations

In this thesis, set thicknesses are used to estimate the paleohydraulics (paleodischarge and give magnitudes for paleocurrent directions) of the ancient river system which deposited the Parthenon Sandstone in northwest Arkansas. Set thickness is the vertical thickness of a group of strata conformable series (Mckee and Weir, 1953); set thickness represents truncated dunes. The goal of this thesis is to: 1) obtain paleodischarge estimates of the Parthenon sandstone via cross-sets and compare the results with previously calculated discharge estimates which use basin area to discharge collation techniques and 2) use paleodischarge estimates calculated within this thesis to give magnitude to …

Sensitivity Of Mangrove Range Limits To Climate Variability, Kyle C. Cavanaugh, Michael J. Osland, Remi Bardou, Gustavo Hinojosa-Arango, Juan M. Lopez-Vivas, John D. Parker, Andre S. Rovai

United States Geological Survey: Staff Publications

Aim: Correlative distribution models have been used to identify potential climatic controls of mangrove range limits, but there is still uncertainty about the relative importance of these factors across different regions. To provide insights into the strength of climatic control of different mangrove range limits, we tested whether temporal variability in mangrove abundance increases near range limits and whether this variability is correlated with climatic factors thought to control large scale mangrove distributions.

Location: North and South America.

Time period: 1984–2011.

Major taxa studied: Avicennia germinans, Avicennia schuaeriana, Rhizophora mangle, Laguncularia racemosa.

Methods: We characterized temporal variability in the enhanced …

Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening

Theses and Dissertations

Nutrient pollution originating from agricultural regions in the Midwest is a serious issue, leading to pollution of drinking water sources as well as large hypoxic zones in the Gulf of Mexico. The source of much of this contamination has been shown to be runoff from agricultural fields in the Upper Mississippi River Basin. One method that has been shown to reduce this pollution from the Upper Mississippi River Basin is the planting of winter cover crops. Winter cover crops such as rye and tillage radish have been shown to significantly reduce nitrate exported from agricultural fields, even in tile-drained watersheds …

Creating A Scaling Relationship Between Peak Discharge And Drainage Area To Identify Tile Drainage Inputs Into An Agricultural Stream, Ryan Plath

Theses and Dissertations

Tile drains have been shown to contribute to high levels of nitrate in agricultural streams. Locations of tile drains on a watershed scale, however, are often unknown due to tile drains being located on many separate parcels of private property. This study evaluates the ability of a methodology, using scaling relationships between discharge and drainage area, for locating areas of large tile drainage contribution to Money Creek, in McLean County, Illinois. Additionally, this study examines the difference in scaling relationships and physical stream hydrology between tileflow and no-tileflow conditions. Eight stream sites were created in the watershed, that recorded stage …

Vegetation Habitat Mapping Of Mammoth Cave National Park Using Multi-Date Landsat-8 Imagery And Lidar Data, Hongli Yang

Steeplechase: An ORCA Student Journal

Vegetation habitat mapping can be regarded as a model predicting the geographic distribution of plant cover types from mapped environmental variables. This paper discusses three environmental factors- slope, aspect and bedrock geology that determined different habitat types in Mammoth Cave National Park. The variation of aspect and slope can largely determine the amount of solar radiation and water available to vegetation, which influences the contrasting habitat types formed in a long term. Bedrock geology, one of the most influential factor in the study area, primarily controls the soil types and drainage conditions that support the various habitat types. The habitat …

Concentration Of Metals Associated With The Native Copper Deposits Of Northern Michigan, Daniel R. Blakemore, C. Renee Sparks, Nathaniel H. Bos

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Keweenaw Peninsula of northern Michigan is home to the largest accumulation of native copper in the world. Native copper deposits are hosted in the 1.1 billion-year old midcontinent rift which extends from Kansas, up through Lake Superior, around into lower Michigan, but is only exposed in the Keweenaw region. Native copper is found in the vesicular and brecciated flow tops of the volcanism associated with this rift, within the interflow conglomerate that developed in-between individual flows, and also minor native copper deposits are found with the copper sulfide deposits in the Nonesuch Shale. The purpose of this study was …

Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard

International Journal of Speleology

Evaporite karst throughout the Gypsum Plain of west Texas is complex and extensive, including manifestations ranging from intrastratal brecciation and hypogene caves to epigene features and suffosion caves. Recent advances in hydrocarbon exploration and extraction has resulted in increased infrastructure development and utilization in the area; as a result, delineation and characterization of potential karst geohazards throughout the region have become a greater concern. While traditional karst surveys are essential for delineating the subsurface extent and morphology of individual caves for speleogenetic interpretation, these methods tend to underestimate the total extent of karst development and require surficial manifestation of karst …

Quantitative River Profile Analysis To Investigate Exhumation Of The Siwalik Foreland Basin, Nepalese Himalaya, Indu Bhattarai

Masters Theses & Specialist Projects

The Nepalese Himalaya, one of the most active regions within the Himalayan Mountain belt, is characterized by a thick succession of Miocene age Siwalik sedimentary rocks deposited at its foreland basin. To date, much of its tectonic evolution, including exhumation in the Nepalese Siwalik, is poorly understood. This study of a quantitative analysis of the bedrock river parameters should provide crucial information regarding tectonic activities in the area. The study investigated geomorphic parameters of river longitudinal profiles from 54 watersheds within the Siwalik section of the Nepalese Himalaya, for the first time. A total of 140 bedrock rivers from these …

Assessing Seasonal And Spatial Variability In The Hydrogeochemistry Of Glacial Meltwater In Iceland, Anisha Tuladhar

Masters Theses & Specialist Projects

A detailed comparative geochemical characterization of three different types of Iceland glacial systems was conducted during June, August, and October, 2016. The study was carried out at a total of 11 outlet glacier rivers flowing from the icecaps Vatnajökull, Eyjafjallajökull, and Mýrdalsjökull. A total of 75 grab samples were collected (25 for each sampling period). The hydrogeochemical variations of Icelandic glacial meltwater are influenced by volcanic activity, temporal changes, and geographical location, which differed between the sampling sites within the glaciers and icecaps. Lower pH range, and comparatively higher and variable specific conductivity, SO4, S and F is linked to …

Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh

Masters Theses & Specialist Projects

Research has demonstrated that equivalent temperature (T_E), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used T_E to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and T_E are smaller under dry atmospheric conditions …

Characterizing South American Mesoscale Convective Complexes Using Isotope Hydrology, Kyle J. Hogancamp

Masters Theses & Specialist Projects

Mesoscale convective complexes (MCCs) over subtropical South America contribute an average annual volume of precipitation equal to approximately seven km3 and occur with an average regularity in the region, with more than 30 per warm season. Isotopic characteristics of precipitation, such as δ2H and δ18O values, provide information that can be used to identify unique processes and sources related to precipitation events. The largest database of isotope characteristics of precipitation within the region is the Global Network of Isotopes in Precipitation (GNIP), which provides varying temporal resolution data from stations around the world, including subtropical South America.

Using this database, …

Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright

School of Geosciences Faculty and Staff Publications

Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies …

Modeling Channel Response To Dam Removal In Lansing, Michigan, Using Swat, Ryan Filbin

Masters Theses

The removal of dams has increased in recent decades in the United States, largely resulting from decaying infrastructure and greater efforts to restore rivers to a more natural, free-flowing state. Dam removal presents the opportunity for increased public safety, improved environmental prosperity, and improved economic prosperity in conjunction with riverfront revitalization projects. The City of Lansing, Michigan, contains two moderate-to high-risk dams along the Grand River that pose a significant risk to the surrounding area in the event of structural failure.

The Soil and Water Assessment Tool (SWAT) is applied to model the impacts of the Moores Park Dam and …

Evolution Characteristics Of Landscape Ecological Risk Patterns In Coastal Zones In Zhejiang Province, China, Jialin Li, Ruiliang Pu, Hongbo Gong, Xu Luo, Mengyao Ye, Baixiang Feng

School of Geosciences Faculty and Staff Publications

Analyzing evolution characteristics of landscape ecological risk patterns would help establish ecological risk early warning mechanism, reduce the ecological risk probability and promote coastal landscape pattern optimization. In this study, landscape pattern indices were first calculated by using multitemporal Landsat TM images acquired in years 1990, 2000 and 2010, then landscape ecological risk pattern evolution models and the spatiotemporal evolutions of ecological risk patterns of coastal zones in Zhejiang province, China were constructed and analyzed. The results demonstrate that (1) greater changes have taken place in landscape structures during the two decades, and (2) the areas of cropland, sea, woodland …

Holocene Winter Climate Variability In Central And Eastern Europe, Aurel Perşoiu, Bogdan P. Onac, Jonathan G. Wynn, Maarten Blaauw, Monica Ionita, Margareta Hansson

School of Geosciences Faculty and Staff Publications

Among abundant reconstructions of Holocene climate in Europe, only a handful has addressed winter conditions, and most of these are restricted in length and/or resolution. Here we present a record of late autumn through early winter air temperature and moisture source changes in East-Central Europe for the Holocene, based on stable isotopic analysis of an ice core recovered from a cave in the Romanian Carpathian Mountains. During the past 10,000 years, reconstructed temperature changes followed insolation, with a minimum in the early Holocene, followed by gradual and continuous increase towards the mid-to-late-Holocene peak (between 4-2 kcal BP), and finally by …

Naturally Occurring Acid Rock Drainage In The Anaconda-Pintler Mountain Range, Montana: A Case Study Of Geochemistry In Two Streams Flowing From Mount Evans, Margaret Doolittle

Graduate Theses & Non-Theses

Mount Evans is located in the Anaconda-Pintler mountain range of southwest Montana approximately 22 km southwest of Anaconda, Montana. Mount Evans appears reddish orange on Google Earth amongst the rest of the mountain range which is a grey white color, indicating the presence of limonite staining and probable sulfide mineralization. In addition, two streams draining opposite sides of the mountain, and either side of the continental divide have conspicuous white coatings on boulders that are clearly visible with Google Earth. During a mineral resource assessment in the 1980s, the USGS suggested that the Mount Evans area could be the top …

Influence Of Internal Variability On Population Exposure To Hydroclimatic Changes, Justin S. Mankin, Daniel Viviroli, Mesfin Mekonnen, Arjen Y. Hoekstra, Radley M. Horton, Jason E. Smerdon, Noah S. Diffenbaugh

Daugherty Water for Food Global Institute: Faculty Publications

Future freshwater supply, human water demand, and people’s exposure to water stress are subject to multiple sources of uncertainty, including unknown future pathways of fossil fuel and water consumption, and ‘irreducible’ uncertainty arising from internal climate system variability. Such internal variability can conceal forced hydroclimatic changes on multi-decadal timescales and near-continental spatial-scales. Using three projections of population growth, a large ensemble from a single Earth system model, and assuming stationary per capita water consumption, we quantify the likelihoods of future population exposure to increased hydroclimatic deficits, which we define as the average duration and magnitude by which evapotranspiration exceeds precipitation …

Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan

Earth, Environment & Sustainability: Faculty Publications

Studies of dissolved organic matter (DOM) transport through terrestrial aquatic systems usually start at the stream. However, the interception of rainwater by vegetation marks the beginning of the terrestrial hydrological cycle making trees the headwaters of aquatic carbon cycling. Rainwater interacts with trees picking up tree-DOM, which is then exported from the tree in stemflow and throughfall. Stemflow denotes water flowing down the tree trunk, while throughfall is the water that drips through the leaves of the canopy. We report the concentrations, optical properties (light absorbance) and molecular signatures (ultrahigh resolution mass spectrometry) of tree-DOM in throughfall and stemflow from …

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder

USF Tampa Graduate Theses and Dissertations

In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …

Exploration Of The Northern Illinois Bedrock Surface, Matthew Rhoads

Theses and Dissertations

The purpose of this study is to deconstruct the relationship between the Leaf River anticline and the preglacial bedrock paleo topography at the eastern terminus of the Plum River Fault Zone in Ogle County, Illinois. A geostatistical approach was used to model the subsurface elevation of the bedrock paleo topography and the Leaf River anticline. The contour maps derived from the elevation models provided detailed depictions of the ancient bedrock landscape and subsurface structure in the study area. The Leaf River anticline is interpreted to be a component of hanging wall anticline at the terminus of the Plum River Fault …

A Numerical Model Investigation Of The Role Of The Glacier Bed In Regulating Grounding Line Retreat Of Thwaites Glacier, West Antarctica, Michael Scott Waibel

Dissertations and Theses

I examine how two different realizations of bed morphology affect Thwaites Glacier response to ocean warming through the initiation of marine ice sheet instability and associated grounding line retreat. A state of the art numerical ice sheet model is used for this purpose. The bed configurations used are the 1-km resolution interpolated BEDMAP2 bed and a higher-resolution conditional simulation produced by John Goff at the University of Texas using the same underlying data. The model is forced using a slow ramp approach, where melt of ice on the floating side of the grounding line is increased over time, which gently …

Responses Of Terrestrial Ecosystem Phosphorus Cycling To Nitrogen Addition: A Meta-Analysis, Qi Deng, Dafeng Hui, Samuel Dennis, Chandra Reddy

Agricultural and Environmental Sciences Faculty Research

Aim

Anthropogenic additions of nitrogen (N) are expected to drive terrestrial ecosystems toward greater phosphorus (P) limitation. However, a comprehensive understanding of how an ecosystem's P cycle responds to external N inputs remains elusive, making model predictions of the anthropogenic P limitation and its impacts largely uncertain.

Location

Global.

Time period

1986-2015.

Major taxa studied

Terrestrial ecosystems.

Methods

We conducted a meta-analysis including 288 independent study sites from 192 articles to evaluate global patterns and controls of 10 variables associated with ecosystem P cycling under N addition.

Results

Overall, N addition increased biomass in plants (+34%) and litter (+15%) as …

On The Relationship Between Spring Nao And Snowmelt In The Upper Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study examines the relationship between the North Atlantic Oscillation (NAO) and snowmelt in spring in the upper southwestern states of the United States (UP_SW) including California, Nevada, Utah, and Colorado, using SNOTEL datasets for 34 yr (1980–2014). Statistically significant negative correlations are found between NAO averages in the snowmelt period and timings of snowmelt (i.e., positive NAO phases in spring enhance snowmelt, and vice versa). It is also found that correlations between El Niño–Southern Oscillation and snowmelt are negligible in the region. The NAO–snowmelt relationship is most pronounced below the 2800-m level; above this level, the relationship becomes weaker. …

Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo

Theses and Dissertations

Nutrients such as nitrate and phosphorus are necessary for life, but excessive amounts can be detrimental. Large amounts of nutrients entering bodies of water can lead to hypoxic zones such as the one in the Gulf of Mexico. Nutrients are also problematic in drinking water reservoirs, as high concentrations of nitrate in drinking water can cause health conditions such as blue baby syndrome and high phosphorus concentrations can lead to algal blooms. Suspended sediment leads to reservoir sedimentation, habitat degradation, and is able to transport particulate nutrients. High nutrient and sediment concentrations are a recurring problem in the drinking water …

Evaporite Karst In Italy: A Review, Jo De Waele, Leonardo Piccini, Andrea Columbu, Giuliana Madonia, Marco Vattano, Chiara Calligaris, Ilenia D’Angeli, Mario Parise, Mauro Chiesi, Michele Sivelli, Bartolomeo Vigna, Luca Zini, Veronica Chiarini, Francesco Sauro, Russell Drysdale, Paolo Forti

International Journal of Speleology

Although outcropping rarely in Italy, evaporite (gypsum and anhydrite) karst has been described in detail since the early 20^th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche), Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent …

Effects Of Anthropogenic Activity On The Green Swamp Preserve Ecosystem, Barbara Ann Nordheim-Shelt

USF Tampa Graduate Theses and Dissertations

The Green Swamp Preserve is a large geographic area that has sustained many changes since Europeans settled in Florida. There has been little published research on the impacts of anthropogenic activity on this system. This thesis research seeks to document more recent changes in the Green Swamp and to evaluate the effects of various human activities on the system. The study period is from 1985 to 2015. For this time period changes in land use and landcover were examined using neural network classifications. Changes in vegetation health were evaluated by examining Normalized Difference Vegetation Index (NDVI) and Green Vegetation Index …

The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus

Earth and Planetary Sciences ETDs

Near Abiquiu in northern New Mexico, the skeletal remains of two mammoths were discovered in the summer of 2014 in the near-surface deposits of a very small alluvial channel. The channel occupies a depression on the backtilted top of a Toreva slump block, a highly unusual setting for a mammoth burial. Geomorphological investigation of the site has provided insight into processes leading to burial and preservation of the remains, as well as local environmental change. Field mapping of sediment sources and LiDAR scans of the contributing slope basin and slump bench provided a map of geomorphic features and surficial geologic …

Unusual Geologic Evidence Of Coeval Seismic Shaking And Tsunamis Shows Variability In Earthquake Size And Recurrence In The Area Of The Giant 1960 Chile Earthquake, M. Cisternas, E. Garrett, R. Wesson, T. Dura, Lisa L. Ely

All Faculty Scholarship for the College of the Sciences

An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca-South American plate boundary. A 500-m long coastal outcrop on Isla Chiloé, midway along the 1960 rupture, provides continuous exposure of soil horizons buried locally by debris-flow diamicts and extensively by tsunami sand sheets. The diamicts flattened plants that yield geologically precise ages to correlate …