GIS STUDIES AND GEOCHEMISTRY OF SELECTED CAMBRIAN IGNEOUS ROCK UNITS IN THE SOUTHERN OKLAHOMA AULACOGEN

Type: Graduate
Author(s): Michael Mbah Geological Sciences Esayas Gebremichael Geological Sciences
Advisor(s): Richard Hanson Geological Sciences
Location: SecondFloor, Table 8, Position 3, 1:45-3:45

The Wichita Mountains in southwestern Oklahoma hold over a billion years of geological history, offering valuable insights into rift dynamics, magmatism, and basin evolution. These mountains are remnants of the Southern Oklahoma Aulacogen, a failed rift that initially formed during the Cambrian period through crustal extension but was later uplifted due to tectonic inversion. The region features a diverse range of igneous and sedimentary rocks, including the Carlton Rhyolites, gabbroic anorthosites, and granites of the Wichita Granite Group, which reflect a complex magmatic history. Over time, major tectonic events such as the Pennsylvanian uplift during the formation of Pangea and subsequent Permian burial played a key role in shaping the area's present landscape. This study utilizes Geographic Information Systems (GIS) tools to examine the spatial relationships, structural features, and lithological distribution of the Wichita Mountains. Using remote sensing, digital elevation models (DEMs), and geospatial analysis, this research provides a deeper understanding of the regions geological history and demonstrates the effectiveness of GIS technology in structural geology and regional mapping.

Quenched and disrupted dacitic to rhyolitic hyaloclastie complex emplaced at shallow levels beneath the seafloor in a Devonian submarine island-arc sequence in the northern Sierra Nevada, California

Type: Graduate
Author(s): Quinton Mindrup Geological Sciences Richard Hanson Geological Sciences
Advisor(s): Richard Hanson Geological Sciences
Location: Basement, Table 4, Position 1, 1:45-3:45

The Devonian Sierra Buttes Formation (SBF) occurs at the base of a thick succession of submarine Paleozoic island arc strata in the northern Sierra Nevada. Bulk eastward rotation of the succession has provided cross-sectional views of a variety of SBF volcaniclastic deposits, radiolarian chert and associated hypabyssal intrusions. The area of concern herein is centered on the prominent glaciated Sierra Buttes peaks, from which the formation takes its name. Coeval andesitic to rhyolitic hypabyssal intrusions form a complex assemblage making up much of the SBF in this area. The assemblage contains a large intrusive hyaloclastite complex within which dacitic-rhyolitic bodies are chaotically dispersed. The intrusions developed when ascending batches of magma were unable to penetrate thick sequences of unlithified sediment and instead intruded into and were quenched against them at shallow levels beneath seafloor.

Here we report results of detailed mapping of glaciated outcrops that occupy an area of ~ 245,000 m2 within the intrusive assemblage and consist mostly of dacite and rhyolite. The assemblage contains large amounts of massive fragmental material with clasts typically < 3 cm in length and ranging down to fine ash. Much of this material consists of angular, originally glassy hyaloclastite shards that formed by nonexplosive quench fragmentation of magma intruding into wet sediment. Ellipsoidal bodies, elongate tubes several meters in length with elliptical cross-sections, and irregular amoeboid bodies occur within the hyaloclastite matrix and are interpreted to represent parts of a branching, interconnected feeder system that supplied magma to the growing fragmental mass beneath the sea floor.

Using Battery Energy Storage Systems with Renewable Energy to Strengthen the Texas Power Grid

Type: Undergraduate
Author(s): Isabella Moreno Environmental Sciences Garrison Kelly Geological Sciences
Advisor(s): Esayas Gebremichael Geological Sciences
Location: Third Floor, Table 10, Position 2, 1:45-3:45

HYDROGEOCHEMICAL ASSESSMENT OF THE SPATIOTEMPORAL EVOLUTION OF GROUNDWATER IN TEXAS AQUIFERS (1985-2014)

Type: Graduate
Author(s): ELVIS OWUSU Geological Sciences
Advisor(s): OMAR HARVEY Geological Sciences
Location: Basement, Table 12, Position 2, 1:45-3:45

Due to the increasing industrial activities, domestic and agricultural demands in Texas render groundwater resources under severe pressure. Texas growing population of 29.5 million in 2021 is projected to reach 51 million by 2070 placing increasing pressure on groundwater, a vital resource for agriculture, industry and municipal use.
This study assesses the hydrogeochemical evolution of Texas nine (9) major aquifers over three decades (1985-2014) and leveraged data from the Texas Water Development Board, Satellite (Landsat 8) dataset from Center for hydrometeorology and Remote sensing, Land use and land cover (Landsat 8/9) dataset from Multi Resolution Land Characteristics were analyzed.
Results indicate a transition in groundwater types across aquifers such as Ogallala, Seymour, Pecos Valley, Edwards Trinity and Edwards Balcones, but Hueco Mesilla Bolson, Carrizo Wilcox and Gulf Coast remain chemically stable with the Trinity aquifer showing a slight variation in its ionic composition. Rock-water interaction and evaporation are the primary mechanism that controls groundwater chemistry and its influence by the weathering of silicate minerals, carbonate dissolution and evaporite dissolution.
Precipitation rates and Land cover changes also play a significant role in the hydro geochemistry of groundwater. Precipitation acts a climate driver for groundwater chemistry, Low precipitation enhances rock-water interaction while high precipitation dilutes solutes and refreshes the aquifer. An increase in developed areas increases abstraction of groundwater which lowers the groundwater level and increases mineral dissolution. This study highlights how hydrogeochemical assessment and remote sensing together offer vital insights into groundwater evolution, supporting adaptive and sustainable water management in Texas.

Geochemistry of Ediacaran-Ordovician diabase, lamprophyre and phonolite dikes in southern Colorado, possibly related to rifting in the Southern Oklahoma Aulacogen

Type: Graduate
Author(s): Caleb Perkey Geological Sciences Richard Hanson Geological Sciences
Advisor(s): Richard Hanson Geological Sciences
Location: Basement, Table 6, Position 1, 1:45-3:45

The Southern Oklahoma aulacogen is a northwest-trending structure containing abundant igneous rocks representing the remains of a major Cambrian rift zone. Previous geologists have mapped numerous igneous intrusions in Colorado that follow the same trend, ranging from Ediacaran to Ordovician in age, and have speculated that these intrusions may be a part of the same rift. These intrusions include abundant igneous dikes of various compositions that originated from deeper magmatic bodies, filling fracture systems in older igneous rocks and Precambrian gneisses. This study involves the geochemical analysis of samples we collected from different dike types, including diabase, lamprophyre, phonolite, and nepheline syenite. The dikes include a prominent diabase dike swarm in the Gunnison area as well as abundant dikes of several types in the Wet Mountains and Front Range farther east. On the discrimination and REE diagrams, fifteen representative dike samples from both sample regions plot tightly together, indicating the clustered dikes share a petrogenetic history of E-MORB-type magma that interacted with intercontinental lithosphere.
We have not yet found diabase dikes in the Wet Mountains suitable for geochemical studies. However, five samples from NW- to NNW-trending diabase dikes in the Front Range, ~80 km north of the Wet Mountains, are among the fifteen diabase samples that cluster together on the geochemical diagrams. This raises the intriguing possibility that dikes related to Ediacaran-Ordovician intraplate magmatism in Colorado may be more extensive than previously thought.
Samples of four lamprophyre dikes in the Wet Mountains exhibit uniform patterns in REE diagrams and plot within the same field on the Winchester and Floyd (1977) classification diagram. Three dikes classified as trachytes by other workers cluster plot in the phonolite field on this diagram, suggesting some of these dikes were previously misclassified. These three dikes also show similar REE patterns with prominent negative anomalies, implying prolonged fractional crystallization.