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GEOL2021JAGODZINSKI8177 GEOL

The Effect of Online Coursework on Student Learning and Achievement Gaps

Type: Undergraduate
Author(s): Adrianna Jagodzinski Geological Sciences
Advisor(s): Michael Pelch Geological Sciences
Location: Zoom Room 2, 02:23 PM

Teachers have experimented with the idea of virtual learning and its’ effects on student achievement. Due to the coronavirus pandemic, many schools and universities transitioned from traditional classroom-focused learning to asynchronous online learning. Asynchronous online learning is a type of instruction where online learning is not happening at the same time or place. Consequently, TCU made the abrupt transition in the Spring of 2021 to fully online asynchronous courses. To understand the magnitude of how remote learning can effect students’ academic success, my research project looks at what factors, including remote learning, can predict final grade utilizing GEOL 10113 student performance data and survey data from the spring semester of 2020 surveys. To investigate the impact of online learning, I tested several linear models to determine what confounders have a significant role in predicting students’ success in online and in remote learning. These models investigated which factors, ranging from demographic information to GPA, are significant predictors of both final grade and remote grade. I started the linear model selection process by testing a complex linear model, which had all the possible factors including interactions that can impact final grade or remote grade from the surveys. Once I knew which factors were significant from the complex model, I eliminated non-significant variables and created new models, comparing each model by their AIC values until I found the best-fit linear model for final grade and remote grade. AIC is a measurement of how well a linear model fits and the lower the AIC value the better fit the linear model has. After testing each linear model: GPA, students’ lecture section, remote grade, and exam average were significant to final grade. These models suggest that while remote grade is a significant predictor of final grade, no variable measured in this study is significant enough to impact remote grade. Differing from previous research, my results showed that there were no gaps in achievement amongst gender and underrepresented minority students. Although statistically no variable significantly impacted remote grade, there are trends amongst demographic variables and remote grade, suggesting some potential relationships that could be explored in future studies.

(Presentation is private)

GEOL2021KING27157 GEOL

A GIS Based Evaluation of the Effectiveness of Trees to Mitigate Urban Heat Island Effects in Fort Worth, Texas

Type: Graduate
Author(s): Charles King Biology
Advisor(s): Esayas Gebremichael Geological Sciences
Location: Zoom Room 4, 12:38 PM

The Urban Heat Island (UHI) effect is characterized by the differential heating of densely populated urban areas in comparison to surrounding areas. Increased temperatures caused by buildings and other man-made infrastructure have a wide range of human and ecological impacts. One emerging methodology to combat UHI effects is the implementation of urban green spaces and trees. Trees can provide two main functions that aid in cooling; shade from the sun provided by the canopy and cooling through the process of evapotranspiration. This project aims to identify which species of tree best suits the ecoregion of Fort Worth, how much feasible green space Fort Worth can provide, and project the cooling the green spaces could provide if they are planted with trees.

(Presentation is private)

GEOL2021KING37552 GEOL

Continued Monitoring of Land Subsidence in Mexico City, Mexico using InSAR Methodology

Type: Graduate
Author(s): Charles King Biology
Advisor(s): Esayas Gebremichael Geological Sciences
Location: Zoom Room 1, 03:19 PM

The use of Interferometric Synthetic Aperture Radar (InSAR) to analyze the deformation of the Earth's surface has become an increasingly important tool for monitoring earthquakes, volcanic activity, landslides, and land subsidence. This process works by calculating the phase differences of radar signals reflected from the Earth's surface over a period of time. If the land has uplifted or subsided, the phase of the two radar signals will interfere. The image this phase difference produces is known as an interferogram, which shows the ground-surface displacement of the target area across the two time periods. This technique has been used extensively to survey Mexico City, which has been an area of concern since the beginning of the 20th century due to its dramatic rate of ground subsidence.

(Presentation is private)

GEOL2021LAM52344 GEOL

Evaluating the Properties of Coffee Derived Carbon-Based Materials for the Removal of Lead from Contaminated Water

Type: Undergraduate
Author(s): Amy Lam Environmental Sciences
Advisor(s): Omar Harvey Geological Sciences
Location: Zoom Room 1, 01:18 PM

The reusing, recycling, and reduction of waste streams is seen as a viable sustainability strategy. One major waste stream is coffee grounds with about 11.5 million kilograms being generated per day in America of which 90% is landfilled. This waste stream can be repurposed into usable carbon-based materials to address issues of climate, pollution, or engineering applications. For my research, I am converting spent (used) coffee grounds into biochars, a type of carbon-based material, with different charring (burning) temperature to measure the removal of lead (Pb2+) from contaminated water. The charring temperature was changed in order to determine the optimal charring temperature for water treatment. This presentation will go into the maximum amount of lead the biochars can remove, how fast the biochars can remove the lead and the properties of biochars that allow for such removal. Further results, methodology, and modeling applications will be discussed in the presentation.

(Presentation is private)

GEOL2021MANZI12370 GEOL

Organic nanomaterials-ferrihydrite interactions

Type: Graduate
Author(s): Aurore Manzi Geological Sciences
Advisor(s): Omar Harvey Geological Sciences
Location: Zoom Room 2, 03:43 PM

Nanomaterials are the new technologies reforming industrial activities. They are used to improve energy efficiency and storage, to cheaply store and process information in every internet server and personal computer, to facilitate bio-imaging and drug delivery, and in environmental remediation. These materials’ nanometric dimension, 1/100000 the width of a human hair, allows them to have novel characteristics such as strength, electrical resistivity, and conductivity, and optical absorption compared to the same materials in bigger sizes. Due to their widespread and incorporation into consumer products, it is important to understand their interactions with other elements in the environment. I used flow experiments, to understand the effects of the core and terminal groups chemistries of 3 sets of nanomaterials on their interaction with ferrihydrite, a very common and reactive mineral in the environment. The nanomaterials used in this study, namely Graphene Quantum Dot (GQD), PAMAM G4-OH, and PAMAM G3.5-COOH, have comparable sizes, 6nm, 4.5 nm, and 3.5 nm, respectively. When the experiments were conducted under acidic and circumneutral pH, the quantities of GQD and PAMAM G4-OH sorbed were equivalent and less than the quantity of PAMAM G3.5-COOH sorbed. In my presentation, I will go over the quantities and kinetics results from the interactions of the 3 sets of nanomaterials onto ferrihydrite over environmentally significant pH values (range 3-10).

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GEOL2021MANZI34816 GEOL

Remote sensing of geothermal potential: Rwanda

Type: Graduate
Author(s): Aurore Manzi Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences
Location: Zoom Room 1, 12:30 PM

Land surface temperature is a major factor used in the assessment and understanding of several processes including global climate, hydrological, geo-/biophysical, urban land use/land cover (Avdan and Jovanovska, 2016). Since the Soviet Union launched the world's first artificial satellite, Sputnik 1, in 1957 there have been about 8,900 satellites from more than 40 countries launched in space that have opened possibilities to understand the earth using remote sensing. Specifically, LANDSAT 8’s thermal infrared sensor Band 10 data has been successfully used to map land surface temperature. The specific algorithm used to derive land surface temperature from LANDSAT 8’s thermal infrared sensor Band 10 showed standard deviations of 2.4°C and 2.7°C on the first trial and second trial respectively (Avdan and Jovanovska, 2016). In my project, I used land surface temperature in addition to secondary data (geologic features, volcanoes, faults, change in cities' extents) to locate and deduce the potential geothermal plays in Rwanda. I also compared the potential geothermal plays obtained using remote sensing to those obtained using ground measurements to assess how accurate remote sensing tools are in determining geothermal plays.

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GEOL2021MCLAIN19804 GEOL

Volcanic risk assessment of Mount Rainier using GIS methods

Type: Graduate
Author(s): Guthrie McLain Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences
Location: Zoom Room 2, 01:58 PM

Mount Rainier is a stratovolcano within the Cascade Arc situated southeast of the cities of Seattle and Tacoma. This region of Washington has undergone substantial population growth while being situated in the shadow of a large stratovolcano. Historically lahar flows, volcanoclastic debris flows, from the volcano have reached as far as Tacoma and could still pose a risk to Seattle and other smaller communities. Seismicity and annual precipitation are large contributors into predicting an eruption event as well as eruption severity. Using ArcGIS Pro and implementing various types of data including historic lahar deposit extent, population growth, seismic activity, and other contributions that can peer into a future volcanic eruption, it can be possible to assess the volcanic hazard Mount Rainier poses on nearby communities.

(Presentation is private)

GEOL2021MORALES30537 GEOL

Interactions of environmentally significant anti-inflammatory drugs with nanocrystalline iron-oxides

Type: Undergraduate
Author(s): Evelyn Morales Geological Sciences
Advisor(s): Omar Harvey Geological Sciences
Location: Zoom Room 1, 03:27 PM

Anti-inflammatory drugs such as ibuprofen and triclosan are widely used and available in many pharmaceutical and personal care products (PPCP’s). The concentrations of these drugs are increasing in public surface and groundwaters and is often linked to negative impacts on aquatic life. These impacts are due to the fact that PPCP’s bypass water treatment facilities since they are not typically regulated and water treatment methods at the facilities are not designed to remove them. My research focuses on removing PPCP’s using reactive environmental sorbents like nanocrystalline ferrihydrite. Specifically, I examined the interaction of two widely used PPCP’s (Ibuprofen and Triclosan) with nanocrystalline ferrihydrite of varying particle size (<125, 125-250, >250). Results thus far show that when Ibuprofen interacts with nanocrystalline ferrihydrite at pH 4.3-4.8; 28.29% was removed when the particle size was less than 125 microns; 45.89% was removed when the particle size was 125-250 microns; and 49.92% was removed when the particle size was greater than 250. While for Triclosan 40.55%, 54.7%, 23.80% was removed by nanocrystalline ferrihydrite with size <125, 125-250, >250 respectively. My presentation will further cover surface properties of nanocrystalline ferrihydrite controlling the sorption of ibuprofen and triclosan.

(Presentation is private)

GEOL2021MUGISHA35937 GEOL

Fungi-induced alterations of Plant Biomass: Impacts on Surface Chemistry, Carbon Sequestration Potential and Sorptive Properties

Type: Undergraduate
Author(s): Jesse Mugisha Environmental Sciences
Advisor(s): Harvey Omar Geological Sciences
Location: Zoom Room 1, 03:11 PM

The changing climate as well as the cycling of nutrients and contaminants throughout our planet is heavily influenced by interactions involving plant biomass. For example, interactions of plant biomass with soil biota (specifically fungi)regulates climate and pollution by controlling 1) the quantity of CO2 released from the respiration of organic matter and 2) the movement of pollutants on land and in water. This study focused on 1) investigating fungal colonization of coffee grounds, as a model for understanding the fungi-plant biomass interactions in soils, and 2) studying how fungal colonization changes in the physical and chemical properties of coffee grounds after molding them for 0,3,4,5 and 7 months. The objectives of the next phase of this research will be to examine how the fungi-induced changes in physical and chemical properties of coffee grounds impact 1)carbon sequestering potential (i.e. ease of respiration to CO2) of the coffee grounds and 2) the capacity of the coffee grounds to bind Gentian violet dye (as a model for organic/cationic pollutant).

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GEOL2021NEWELL30679 GEOL

Size Effects on Sorption of Nanomaterials to Iron Oxides

Type: Undergraduate
Author(s): Brooke Newell Geological Sciences
Advisor(s): Omar Harvey Geological Sciences
Location: Zoom Room 4, 02:31 PM

Synthetic nanomaterials continue to revolutionize how we do things industrially, medically and domestically. As we continue to utilize these materials, the inevitability of them entering the environment and the need to understand the associated consequences rises to the forefront. My research focuses on understanding the chemo-dynamics of interactions between polyamidoamine (PAMAM)-based nanomaterials (most commonly in the biomedical field through drug and gene delivery) and reactive minerals in the environment. Specifically, this presentation will cover the size-dependent binding (and debinding) dynamics of carboxyl-terminated PAMAMs (G-COOH) onto (and from) ferrihydrite (FFH), a form of naturally-occurring iron oxide mineral. Early results suggest that at pH 5, the smaller G1.5-COOH PAMAM binds to (and debinds from) FFH in higher quantities but at much slower rates that the larger G3.5-COOH PAMAM. The higher quantities of G1.5-COOH PAMAM being bound to (or debound) from FFH is attributable to its smaller size - facilitating access to internal micropore space in FFH that are inaccessible by the larger G3.5-COOH PAMAM. Difference in the accessibility of internal FFH micropore space by the different sized PAMAMs would also explain observed trends in their rates of binding and debinding. In future research, I will be targeting the confirmation of early results and the expansion of my study to include G-COOH PAMAMs larger than G3.5-COOH.

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GEOL2021PAREDES51203 GEOL

Functionalization of Pistachio Biochar for Nitrate Removal in Water

Type: Undergraduate
Author(s): Riley Paredes Biology
Advisor(s): Omar Harvey Geological Sciences
Location: Zoom Room 4, 12:46 PM

Nitrate contamination of groundwater has been a growing problem in Texas and California from increased food demands, requiring growing agricultural inputs of synthetic fertilizer and manure. Pyrolysis of pistachio agro-waste is a promising method for reducing waste products and engineering biochar with the capacity to support zerovalent iron impregnation (ZVI). This study examined the efficiency of pistachio biochar for nitrate (NO₃-N) removal in water with and without ZVI. Pistachio biochar was functionalized through varied temperature pyrolysis (400-600℃) over three heating durations (0 min, 5 min, 10 min). Biochar samples from both 400°C and 600℃ pyrolysis were tested with and without ZVI impregnation over a 5 day period in a 20 ppm solution of NO₃-N. The biochar-nitrate solutions were recorded in intervals (1 hr, 3 hr, 7 hr, 24 hr, 68 hr, 96 hr, 120 hr) and Ultraviolet-Visible Spectroscopy was utilized to measure NO₃-N absorbance of samples at 400nm. The experimental data show that pistachio biochar with and without ZVI decreased nitrate levels from water; presenting a potential low-cost and sustainable option for repurposing agro-waste for water remediation.

(Presentation is private)

GEOL2020ALLEN25238 GEOL

Illinois agriculture: An examination of the relationship between annual corn crop yield and the application of Atrazine.

Type: Graduate
Author(s): Dalton Allen Biology
Advisor(s): Esayas Gebremichael Geological Sciences

Herbicides are chemicals frequently used in agriculture to manage or remove unwanted vegetation (i.e., weeds) that may negatively impact crops through resource competition. Through the elimination of these competitors, losses in crop yield may be reduced thus increasing cropland productivity. Atrazine is an herbicide that is widely used in the United States for the control of weeds that is predominately applied in the agriculture of corn, sorghum, and sugarcane. This is of interest to Illinois agriculture, as according to the United States Department of Agriculture (USDA), Illinois is a major agricultural producer of corn and soybeans with corn accounting for 11 million of Illinois’ 27 million acres of cropland. Further, Illinois possesses an agricultural industry that produces more than $19 billion annually of which corn accounts for more than 50 percent. It is due to the economic importance of corn crops to the state of Illinois and the widespread use of Atrazine in the agriculture of corn, that this project seeks to examine the relationship between Illinois annual corn crop yields and Atrazine application. This relationship will be assessed through analysis of spatial data acquired from the USDA for Illinois Atrazine application and corn crop yield.

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GEOL2020KOLLI40047 GEOL

Analysis of Deforestation in Nilgiri Biosphere Reserve

Type: Undergraduate
Author(s): Navya Kolli Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences

Analysis of Deforestation in Nilgiri Biosphere Reserve
This research will focus on Nilgiri Biosphere Reserve, a mountainous region located in the Western Ghats of southern India that encompasses several major national parks. Recent developments have caused mass deforestation in the region for lumber and area for plantations. In addition, more roads are being developed connecting urban centers to Nilgiri, which is only worsening the deforestation issue. In this research, Landsat satellite images will be used to track change over time with regards to deforestation and the development of road networks to see how that impacts wildlife. Geospatial data geoprocessing tools will be used to categorize change in land use over time (the change in some land areas from forest/untouched reserve to agricultural or road). False and true color composites in addition to Normalized Difference Vegetation Index (NDVI) assessments will be undertaken to track the deforestation and differentiate between land types, since vegetation will be in a bright red, soil will be brown, and urban areas will be cyan blue to determine how much live green vegetation there is in the reserve as well.

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GEOL2020KOLLI46982 GEOL

Assessing Land Use Impact on Urban Heat Island Formation in Fort Worth

Type: Undergraduate
Author(s): Navya Kolli Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences

Assessing Land Use Impact on Urban Heat Island Formation in Fort Worth

This research project will focus on assessing the impacts of human activity on the environment in Fort Worth as urbanization has increasingly taken hold over the years. Specifically, the project focuses on analyzing the change in land use in the city over a span of roughly three decades and its contributions to urban heat island formation. Landsat band data products will be used to estimate variations in land surface temperature (LST). LST calculations will highlight the factors contributing to urban heat island formation in Fort Worth.

(Presentation is private)

GEOL2020MUGISHA7301 GEOL

Fungal alterations of Plant Biomass and Impacts on Sorption organic cations: Model study of Coffee grounds and Gentian violet.

Type: Undergraduate
Author(s): Jesse Mugisha Geological Sciences
Advisor(s): Harvey Omar Geological Sciences

Plant biomass represents an important component within the biogeochemical cycling of nutrients and contaminants. Transformation of this plant biomass in the environment to organic residuals is dictated primarily by interactions with micro-organisms specifically fungi. My research investigates the effects of fungal colonization of spent coffee grounds as a model for plant biomass to organic matter transformation and how this transformation impacts environmental stability and its ability to bind to contaminants. This presentation will cover; 1) physical and chemical changes in the spent coffee grounds after molding for 0,3,4,5 and 7 months, 2) how these physical changes impact the environmental degradability, and 3) how these physical and chemical changes impact the capacity to bind Gentian violet dye (as a model for organic cations).

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GEOL2020PRINES56945 GEOL

U-PB DETRITAL ZIRCONS OF SYNOROGENIC CARBONIFEROUS DEEP-WATER CLASTIC DEPOSITS IN THE OUACHITA MOUNTAINS, ARKANSAS, UNITED STATES

Type: Graduate
Author(s): Shaun Prines Geological Sciences Walter Manger Geological Sciences Xiangyang Xie Geological Sciences
Advisor(s): Xiangyang Xie Geological Sciences

The southern margin of the North American continent transformed from a passive margin to an
active margin during the Ouachita orogeny. Thick and near–continuous Paleozoic successions in
the Ouachita Mountains provide a unique opportunity to document changes in both
sedimentation and tectonics. In contrast to well-documented Taconic, Acadian, and Alleghenian
orogenic events, limited detrital zircon studies of the Ouachita orogeny and associated
successions have been published, and sediment sources of these deep-water, synorogenic clastics
remain less constrained.
In this study, a total of six outcrop samples (n=617) from the Mississippian Stanley Group and
Lower-Middle Pennsylvanian Jackfork and Johns Valley Groups were collected and processed
for U-Pb detrital zircon geochronologic analyses to depict sediment sources and dispersal
patterns during the Ouachita orogeny. Results show that the age distributions of the
Carboniferous deep-water clastic deposits in the Ouachita Mountains are characterized by major
peaks of the Paleozoic (~350-500 Ma), Grenville (~900-1350 Ma), and Midcontinental GraniteRhyolite (~1350-1500 Ma), minor peaks of Yavapai-Mazatzal (~1600-1800 Ma) and Superior (>
~2500 Ma) provinces. These deep water clastics share great similarities with the Appalachian
sources and are likely derived from similar sources. From the Mississippian Stanley Group to the
Pennsylvanian Jackfork and Johns Valley Groups, the Yavapai-Mazatzal population shows
marked enrichment (up to ~12%), suggesting Precambrian basement uplifts, possibly related to
the Ancestral Rockies to the northwest, might be another potential source. Compilation and
comparison show the Neoproterozoic age population (~550-800 Ma), most likely associated with
the peri-Gondwana terrane to the south, ranges from 3% to 35% within the Mississippian Stanley
Group. The variation indicates that the Stanley Group may have strong but short-lived local
contribution from the Gondwana terrane in addition to the regional Appalachian sources.
Overall, despite its proximal location, these Carboniferous deep-water clastic deposits in the
Ouachita Mountains received limited contribution from the Ouachita orogenic belt itself.

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GEOL2020TUCKER62356 GEOL

Trail Network Analysis of the TCU Tropical Biology Station

Type: Graduate
Author(s): Mary Tucker Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences Dean Williams Biology

The new world tropics represent an area of unparalleled biodiversity. Unfortunately, it also represents an area of increasing habitat loss and consequently is in dire need of protection and conservation. The TCU San Ramon Tropical Biology Station located on the Caribbean slope of Costa Rica protects 100 hectares of primary and secondary forest and is a unique and ideal location for studying tropical biology. In the summer of 2018, we mapped an updated trail network at the station using a Bad elf sub-meter GNSS receiver in conjunction with Arc Collector. For this project we analyzed the distance each trail traveled through the 3 habitat types found at the station (primary forest, secondary forest, and pasture land), which will be used to aid the sampling efforts of my Master’s thesis project examining how mixed-species foraging flocks utilize the habitat protected by the station.

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GEOL2020WALKER45567 GEOL

Quantifying the Hydrological Setting of Upper Flow Regime Channels of the Triassic Dockum Group of West Texas

Type: Graduate
Author(s): Samuel Walker Geological Sciences John Holbrook Geological Sciences
Advisor(s): John Holbrook Geological Sciences

The Triassic Dockum Group of the western Texas High Plains is studied in depth paleontologically, but until recently lacked a detailed sedimentological evaluation. Recent research of the Dockum Group in Palo Duro Canyon, Texas, provides new interpretations of the complex fluvial lacustrine strata of the comprising formations based on analysis of individual lithofacies. Identified within the lithofacies assemblages are numerous channel belts composed of upper flow regime bedforms. Observed upper flow regime bedforms in outcrop range from upper plane bed, antidunes, breaking antidunes, chutes and pools, and cyclic steps with increasing flow velocity respectively. These channel belts record extreme flow events from repeating massive storms that perpetuated throughout the Texas region of Triassic Pangea. These unique reservoir-quality channels are interpreted to be resultant of a megamonsoonal climate producing massive pulses of rapid flow allowing for the preservation of upper flow regime bedforms. While these channels are identified in outcrop they have not been quantified in distribution, variability in fill, connectivity and formative discharge.
This study aims to test the megamonsoonal hypothesis by quantifying the discharge of these channels and testing if the distribution density and paleodischarge of these channels is consistent with local dominance of megamonsoonal conditions. Upper flow regime structures are rarely preserved in the rock record and extremely difficult to observe directly during natural formation in modern rivers. Most of the equations used to quantify flow conditions for these structures are derived from flume tank experiments. These are applied to the upper flow regime bedforms found in outcrops of the Dockum Group to reconstruct paleohydrology. Current flume tank research reinforces Kennedy’s equations defining relationships between the wavelengths of stable antidune apexes (λ), mean flow depth (hm) and mean flow velocity (U). These equations are modified to account for different upper flow regime structures formed under increasing velocity and discharge identified in outcrop. Bedform distribution, size, and type are variables determined from outcrop measurement. Paleoflow velocities, Froude numbers and relative water depths are determined with an observed margin of error. Scaling relationships and field measurements provide constraints on channel cross sectional area and channel-belt density. This data along with grain size distribution provides tangible numbers for calculating formative discharge. Preliminary results align with data from flume tank experiments and are consistent with major floods produced by substantial storm events verifying the megamonsoonal hypothesis.

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GEOL2020WEST44597 GEOL

Campanian-Maastrichtian Ankylosaurs of West Texas

Type: Graduate
Author(s): Bryanna West Geological Sciences
Advisor(s): Arthur Busbey Geological Sciences

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ENSC2019HUDGENS33438 GEOL

Monarch Butterfly Population Decline

Type: Graduate
Author(s): andrew hudgens Geological Sciences
Advisor(s): Tami Morgan Geological Sciences
Location: Session: 2; Basement; Table Number: 2

presentation location

Monarch butterfly populations in North America have declined by approximately 80% over the last 20 years. Many contributing factors are responsible for this decline, however the loss of Milkweed has been identified as a major factor. Milkweed is the primary food source for Monarch caterpillars. A GIS analysis was performed to identify milkweed resources in the North Texas area.

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GEOL2019CAVES50910 GEOL

Understanding Metal-Silicate Mixing in Mesosiderites

Type: Graduate
Author(s): Lindsay Caves Geological Sciences
Advisor(s): Rhiannon Mayne Geological Sciences
Location: Session: 1; 1st Floor; Table Number: 5

presentation location

Mesosiderites are meteorites composed of equal parts metal and crustal silicate material, which have been linked to the HED parent body 4Vesta. The metal portion of mesosiderites is also compositionally similar to the IIIAB irons. Mesosiderite silicates were mixed with metal, recrystallized and rapidly cooled. The slow metallographic cooling rates recorded by mesosiderite metal indicate mixing followed by deep burial within an asteroidal body. Several models for the formation of mesosiderites have been proposed, but no single model can completely explain their multi-stage history. Oxygen isotope compositions of mesosiderites and eucrites are identical, consistent with the HEDs and mesosiderites originating from a common parent body. However, there are notable differences between the two groups. These include the differing Fe-Mn-Mg systematics in mesosiderite pyroxenes, which reflect an FeO reduction trend and not the magmatic trend seen in the HEDs. Phosphates and tridymite are also more abundant in mesosiderites than howardites and eucrites. These differences have been attributed to redox reactions that occurred during the metal-silicate mixing stage of mesosiderite formation. As previous work focused mainly on the silicate portion, this study examines the metal of five mesosiderite samples of varying petrologic class and degree of metamorphism. Thick sections of each meteorite containing both matrix metal and metal nodules were requested on loan from the National Meteorite Collection, located in the National Museum of Natural History, Department of Mineral Sciences. Electron microprobe (EMP) analyses of both silicate and metal portions of each mesosiderite were collected, as well as LA-ICP-MS analyses of the matrix metal and metal nodules within each section. The dataset will be analyzed for evidence of redox reactions and other processes that may have been occurring during the metal-silicate mixing phase of mesosiderite formation. If redox reactions occurred between the metal and silicate portions of mesosiderites, then: 1) the matrix metal within mesosiderites may be depleted in readily oxidizable elements (e.g. P, W) relative to the metal nodules that are not in contact with the silicate phase; or, 2) all metal in mesosiderites is depleted in readily oxidizable elements. This depletion should be visible when compared to IIIAB irons of a similar composition.

(Presentation is private)

GEOL2019DEBONE30636 GEOL

Newly discovered old volcano in Big Bend National Park

Type: Graduate
Author(s): Kristin DeBone Geological Sciences Tamie Morgan Geological Sciences
Advisor(s): Richard Hanson Geological Sciences
Location: Session: 2; Basement; Table Number: 8

presentation location

Recent field work has discovered a volcanic complex within the Paleocene Black Peaks Formation in the northwestern part of Big Bend National Park in west Texas. This is the only known Paleocene volcano in west Texas. We have identified pyroclastic deposits consisting of ash-sized and coarser clasts, including volcanic bombs and blocks, which were erupted explosively from a nearby vent. Margins of the volcanic complex have been mapped using remote sensing because the volcanic rocks are distinctly different in color from the adjacent shale. Characteristics of the pyroclastics suggest derivation from phreatomagmatic eruptions, which occurred when magma and groundwater violently interacted in the shallow subsurface.

(Presentation is private)

GEOL2019DONAHOO65357 GEOL

Using Non-Invasive Geophysical Techniques in Near-Surface Infrastructure and Agricultural Planning and Management

Type: Graduate
Author(s): Michaela Donahoo Geological Sciences
Advisor(s): Omar Harvey Geological Sciences
Location: Session: 2; 3rd Floor; Table Number: 7

presentation location

Using Non-Invasive Geophysical Techniques in Near-Surface Infrastructure Planning and Management

Michaela Donahoo1, Karim Ouamer-ali2,3, Youcef Daoud2, Kaddour Djili3, Omar R. Harvey1
1Department of Geological Sciences, Texas Christian University, Fort Worth, Texas, USA.
2 National Institute of Agronomic Research of Algeria (INRAA), El-Harrach, Algeria.
3Ecole Nationale Supérieure Agronomique (ENSA), El-Harrach, Algeria.

Understanding soil characteristic variability geospatially as a function of depth and time is key to the optimal implementation of subsurface infrastructure planning and expansion. The soils physical behavior as well as its interaction with piping and road materials determine where such a system could divert and predict future maintenance frequency. Central to the development of site-specific, precision management strategies is the quantification and mapping of the geospatial variability in soil properties at significantly higher resolutions than provided in current soil surveys. The presentation will cover results from ongoing collaborative research efforts between researchers at Texas Christian University and two Algerian institutions in using non-invasive measurements of bulk apparent electrical conductivity (ECa) to quantify and map 3-D soil variability in semi-arid and arid areas of Algeria, Northern Africa. The focus will be on the derivation and application of depth-specific ECa-ECe (saturated paste), ECa-clay content and ECa-water content relationships for use in understanding seasonal salinity and water dynamics within potential depths of construction interest.

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GEOL2019LAMB52985 GEOL

A Source to Sink Analysis of the Dockum Group in the West Texas Highplains

Type: Graduate
Author(s): Grayson Lamb Geological Sciences
Advisor(s): John Holbrook Geological Sciences
Location: Session: 1; 3rd Floor; Table Number: 9

presentation location

The fundamental understanding of any geologic basin stems from ascertaining the relationship between its source and sink. Every basin is therefore identified as a “sink” and has a provisional “source.” The investigation of this fundamental relationship is the preliminary exploration step to further basin development.
The Late Triassic Dockum Group of the west Texas high plains is an understudied group that begs investigation into the source to sink relationship. A comprehensive study of the Dockum Group as a “sink” is here undertaken in order to better understand the paleoclimate and its implications on the Dockum group depositional style. This study focuses on the northern most section of the Dockum group outcrop system. Within the study area it is subdivided into three main formations, the Tecovas mud, Trujillo sand, and Cooper Canyon sand-mud mix system.
This study showcases a forward stratigraphic modeling software, Dionisos Flow. From field based outcrop work: grain size, channel thickness, water discharge, and lithofacies assemblages were quantified as model inputs in Dionisos Flow.
The study aims to model Dockum Group sedimentation in order to determine the plausible paleoclimate, and its related depositional environment and depositional style. To do so, an outcrop study and fluvial architecture analysis was completed to serve as model input variables. Then a forward stratigraphic Dionisos Flow model of the three main Dockum Group formations was generated. It was then analyzed and coupled with the outcrop study to draw conclusions on the necessary Triassic climate conditions to produce the Dockum Group deposits.
Per the modeling exercise and outcrop study it is concluded that the Triassic climate was highly variable, shifting between semi-arid to humid. Its variability has been underemphasized in previous studies. Climate alterations are on a scale of 103 years. Additionally, the Dockum Group’s sedimentation style has been a forum of contradicting theories. This study has concluded that Dockum sands were deposited in a predominantly upper flow regime environment during humid climate cycles, while its abundant muds were deposited in lower flow during semi arid climate cycles.

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GEOL2019MIRKIN10373 GEOL

Background Color Matching in Texas Horned Lizards

Type: Graduate
Author(s): Stephen Mirkin Biology
Advisor(s): Tamie Morgan Geological Sciences
Location: Session: 2; Basement; Table Number: 1

presentation location

Texas horned lizards are a threatened species in the state of Texas with declines attributed to a variety of factors including: habitat conversion, pesticide use and red imported fire ants. These cryptic lizards in their natural habitats utilize a variety of anti-predator defense mechanisms. The primary defensive adaptation to avoid predators is often cited as their cryptic coloration, which is often suggested to color match the background substrates of the regions where they are found. Although background color-matching is purported to be an important factor in horned lizard defensive strategies it has never been empirically tested. Here we present the first known study of background color matching of Texas horned lizards in the state of Texas. We used a GIS analysis using soils and satellite imagery data to test how well Texas horned lizards match the soils and substrate in different regions of Texas.

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