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Full-Text Articles in Earth Sciences

Mgrre_Thinsections_Mgrre-05_13, Mgrre Nov 2022

Mgrre_Thinsections_Mgrre-05_13, Mgrre

Thin Sections

No abstract provided.


Microplastic Pollution And Its Effects On Aquatic And Terrestrial Ecosystems, Anish Kumar Warrier Dr. Nov 2022

Microplastic Pollution And Its Effects On Aquatic And Terrestrial Ecosystems, Anish Kumar Warrier Dr.

Technical Collection

Microplastics (MPs) are tiny pieces of plastics (less than 5 mm in size) that are ubiquitous in the environment. Their existence causes immediate threat to organisms of different sizes living in the water, sediments and soils affecting the food chain. Further, their presence in the marine realm can lead to a delay in the sequestration of carbon dioxide from the atmosphere into the oceans. The Environmental Microplastics Group at the Department of Civil Engineering, MIT, is primarily focused on the detection of microplastics and nanoplastics in the different environmental compartments, i.e., freshwater and marine water, sediments, soils, and biota such …


Mgrre_Thinsections_05_A_68, Mgrre Nov 2022

Mgrre_Thinsections_05_A_68, Mgrre

Thin Sections

No abstract provided.


Filling Critical Gaps In The Space-Time Record Of High Lava Plains And Co-Columbia River Basalt Group Rhyolite Volcanism, Vanessa Marie Swenton, Martin J. Streck, Daniel P. Miggins, William C. Mcintosh Nov 2022

Filling Critical Gaps In The Space-Time Record Of High Lava Plains And Co-Columbia River Basalt Group Rhyolite Volcanism, Vanessa Marie Swenton, Martin J. Streck, Daniel P. Miggins, William C. Mcintosh

Geology Faculty Publications and Presentations

Miocene rhyolitic volcanism of eastern Oregon, USA, can be divided into two main episodes. Mantle plume upwelling is thought to have generated Columbia River Basalt Group (CRBG) lavas and coeval >16.5−15 Ma silicic volcanism trending north−south from northeast Oregon to northern Nevada. Rhyolite volcanism of the 12−0 Ma High Lava Plains province has been ascribed to either buoyancy-driven westward plume spreading or to slab rollback and mantle convection spanning from southeast Oregon to Newberry Volcano to the west. The apparent ca. 15−12 Ma eruptive hiatus suggests that rhyolites of these provinces were a product of separate processes, yet this gap …


College Of Natural Sciences Newsletter, September & October 2022, College Of Natural Sciences Nov 2022

College Of Natural Sciences Newsletter, September & October 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 6

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Midwest Regional ACS Meeting
Page 4 North Central ASM Meeting
Page 5 Geography Department Travel
Page 6-7 Media Coverage of CNS
Page 7 REMAST Program at SDState receives national spotlight
Page 8 Celebrating the lives of those who touched the College
Page 9 Innovative Learning Spaces
Page 10 Open PRAIRIE Data
Page 11 2022 CNS Scholarship Brunch
Page 12-14 Fall 2022 Outreach Events


Geology-Based Shear-Wave Velocity Model Of Reference Site Conditions In South Carolina For Seismic Site Response Analysis, Camilius Amevorku Nov 2022

Geology-Based Shear-Wave Velocity Model Of Reference Site Conditions In South Carolina For Seismic Site Response Analysis, Camilius Amevorku

All Dissertations

Assessing earthquake hazard in the State of South Carolina is important because it is one of the most seismically active regions of the eastern United States and has experienced earthquakes of damaging levels in the historical past. Examples of these damaging seismic events are the 1886 Charleston earthquake (M 6.7 to 7.5) and the 1913 Union County earthquake (M 4.5 to 5.5).

Small-strain shear-wave velocity (VS) is an important parameter in performing site response analysis. The deep nature of the top of reference firm rock (i.e., VS ≥ 760 m/s or B-C boundary) due to …


Snapshots Of Coastal Ecology During Glacial And Deglacial Intervals: A Multiproxy Assessment Of Northern Gulf Of Mexico Sediment Cores, Kendall Emilie Brome Nov 2022

Snapshots Of Coastal Ecology During Glacial And Deglacial Intervals: A Multiproxy Assessment Of Northern Gulf Of Mexico Sediment Cores, Kendall Emilie Brome

LSU Master's Theses

Terrestrial ecosystems along exposed continental shelves during times of relatively low sea level and glaciation are rarely preserved due to the mechanically erosive nature of marine transgression and regression. In this study, I investigate the geochemical and palynological characteristics of two well-preserved sites in the northern Gulf of Mexico (NGOM) to determine the ecologic settings and subsequent mechanisms of preservation in this region. Both sites contain preserved terrigenous sediments of previously exposed coastal margins; the first is located at the Alabama Underwater Forest (~13 km south of Gulf Shores, AL, at ~15 mbsl), and optically stimulated luminescence dates to 72–56 …


Time-Varying Rates Of Organic And Inorganic Mass Accumulation In Louisiana Marshes And Relation To Sea-Level Change, Sophie Vincent Nov 2022

Time-Varying Rates Of Organic And Inorganic Mass Accumulation In Louisiana Marshes And Relation To Sea-Level Change, Sophie Vincent

LSU Master's Theses

Louisiana wetlands are complex systems that require a continuous input of organic and inorganic material to keep pace with relative sea-level rise (RSLR). Marshes, specifically, rely on organic material to build soil volume and maintain surface elevation. Interannual-to-decadal sea-level anomalies induced by Earth's internal climate variability and atmospheric disturbances such as hurricanes can affect marsh accretion, mineral deposition, and plant productivity. Coastal restoration projects such as sediment diversions are in progress to mitigate land loss and increase availability of inorganic sediment to coastal wetlands. The goal of this project is to determine if organic mass accumulation rates in Louisiana marshes …


Stability Of Fishes Assemblage Structure Over A Lustrum In Coastal Wetlands Under Different Disturbances In An Industrial Zone Of The Central Gulf Of Mexico Coast, Carlos E. Cintra-Buenrostro, Alejandro Fierro-Cabo Nov 2022

Stability Of Fishes Assemblage Structure Over A Lustrum In Coastal Wetlands Under Different Disturbances In An Industrial Zone Of The Central Gulf Of Mexico Coast, Carlos E. Cintra-Buenrostro, Alejandro Fierro-Cabo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Shallow coastal wetlands within the territory of an industrial port in southern Tamaulipas, Mexico, were monitored seasonally over a lustrum, focusing on their fishes assemblage and water parameters. The purpose was to characterize these ecosystems that are affected by different disturbances of industrial origin, document changes, and assess potentially degrading terms as the affectations prevailed over the period of study. The wetlands are differentially affected by impacting land uses in their immediate surroundings, by crude oil leaks, and/or by diverse industrial wastewater discharges. Water parameters varied only slightly over time for most sites, and relative disparities among sites remained. The …


Hydrological Drought Forecasting Using A Deep Transformer Model, Amobichukwu C. Amanambu, Joann Mossa, Yin-Hsuen Chen Nov 2022

Hydrological Drought Forecasting Using A Deep Transformer Model, Amobichukwu C. Amanambu, Joann Mossa, Yin-Hsuen Chen

University Administration Publications

Hydrological drought forecasting is essential for effective water resource management planning. Innovations in computer science and artificial intelligence (AI) have been incorporated into Earth science research domains to improve predictive performance for water resource planning and disaster management. Forecasting of future hydrological drought can assist with mitigation strategies for various stakeholders. This study uses the transformer deep learning model to forecast hydrological drought, with a benchmark comparison with the long short-term memory (LSTM) model. These models were applied to the Apalachicola River, Florida, with two gauging stations located at Chattahoochee and Blountstown. Daily stage-height data from the period 1928–2022 were …


Wagin Townsite Borefield: Review Of Aquifer Performance, Rockwater Nov 2022

Wagin Townsite Borefield: Review Of Aquifer Performance, Rockwater

Natural resources commissioned reports

The Wagin Borefield was established by the Department of Agriculture and Food, Western Australia in 2000-2007 to control groundwater levels in the town that had risen to critical levels as a result of increased recharge and runoff following the clearing of native vegetation for urban development and agriculture. Similar investigations were conducted as part of the Rural Towns Program and Rural Towns-Liquid Assets projects in 41 other wheatbelt towns, but none, except perhaps from Merredin, have been as comprehensively implemented, operated and monitored as Wagin.

The Wagin Borefield comprises 8 production bores, of which only 3 have been operated. To …


Mgrre_Thinsections_05_A_67, Mgrre Oct 2022

Mgrre_Thinsections_05_A_67, Mgrre

Thin Sections

No abstract provided.


A Rapid High-Precision Analytical Method For Triple Oxygen Isotope Analysis Of Co2 Gas Using Tunable Infrared Laser Direct Absorption Spectroscopy, Nathan Perdue, Zachary Sharp, David Nelson Jr., Rick Wehr, Christoph Dyroff Oct 2022

A Rapid High-Precision Analytical Method For Triple Oxygen Isotope Analysis Of Co2 Gas Using Tunable Infrared Laser Direct Absorption Spectroscopy, Nathan Perdue, Zachary Sharp, David Nelson Jr., Rick Wehr, Christoph Dyroff

Earth and Planetary Sciences ETDs

Rationale

The simultaneous analysis of the three stable isotopes of oxygen – triple oxygen isotope analysis – has become an important analytical technique in natural sciences. Determination of the abundance of the rare 17O isotope in CO2 gas using magnetic sector isotope ratio mass spectrometry is complicated by the isobaric interference of 17O by ­13C (13C16O16O and 12C16O17O both have mass 45 amu). A number of analytical techniques have been used to measure the 17O/16O ratio of CO2 gas. They …


Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings Oct 2022

Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings

LSU Doctoral Dissertations

Increasing demand for water for agricultural use within the Dougherty Plain of the Southeastern United States has depleted surface water bodies. In karstic landscapes, such as the Dougherty Plain in southwest Georgia where the linkages between surface and ground waters are close, there is a need to understand the physical characteristics of the subsurface that allow these close linkages. Having a better understanding of the subsurface characteristics will aid numerical modeling efforts that underpin policy decisions and economic analyses. Two common features on this karstic landscape are draws and geographically isolated wetlands. Using LiDAR, aerial imagery, and ground-penetrating radar, this …


Mgrre_Thinsections_05_A_66, Mgrre Oct 2022

Mgrre_Thinsections_05_A_66, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_05_A_65, Mgrre Oct 2022

Mgrre_Thinsections_05_A_65, Mgrre

Thin Sections

No abstract provided.


Concentration Of Heavy Metals In Three Distinct Algae Families From Humboldt County, California, Kodiak E. Miller, Caleb J. Strait, Jacob I. Begorre, Brittney L. Mitchell, Claire P. Till Oct 2022

Concentration Of Heavy Metals In Three Distinct Algae Families From Humboldt County, California, Kodiak E. Miller, Caleb J. Strait, Jacob I. Begorre, Brittney L. Mitchell, Claire P. Till

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Anthropogenic impacts on marine environments can impact metal fluxes and concentrations available to marine species. Monitoring these impacts is necessary to better understand the interactions between the biotic and abiotic components of these ecosystems and mitigate the risk posed by harmful toxins introduced by human activities. Biomoniters, like macroscopic algae, are useful indicators that illuminate the bioaccumulation of toxins commonly introduced from anthropogenic activity. With this in mind, the concentrations of heavy metals zinc (Zn), nickel (Ni), and copper (Cu) were analyzed via the assessment of algae (Representatives from Ulva, Mastocarpus, Fucus) in two sites in Humboldt County: …


Mgrre_Thinsections_05_A_64, Mgrre Oct 2022

Mgrre_Thinsections_05_A_64, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_05_A_63, Mgrre Oct 2022

Mgrre_Thinsections_05_A_63, Mgrre

Thin Sections

No abstract provided.


The Role Of Extended Grazing In Profitable Ruminant Livestock Operations, Jim Gerrish Oct 2022

The Role Of Extended Grazing In Profitable Ruminant Livestock Operations, Jim Gerrish

Kentucky Grazing Conference

No abstract provided.


Hay Feeding Strategies To Build Fertility In Grazing Systems, Nick Roy, Fred Thomas Oct 2022

Hay Feeding Strategies To Build Fertility In Grazing Systems, Nick Roy, Fred Thomas

Kentucky Grazing Conference

No abstract provided.


Grazing Myths That Reduce Profitability, Greg Halich Oct 2022

Grazing Myths That Reduce Profitability, Greg Halich

Kentucky Grazing Conference

No abstract provided.


Right Sizing Your Cows For Profit, Les Anderson Oct 2022

Right Sizing Your Cows For Profit, Les Anderson

Kentucky Grazing Conference

No abstract provided.


My Soil Is Alive! Introduction To Soil Life And Its Role In Profitable Grazing Systems, Ray Archuleta Oct 2022

My Soil Is Alive! Introduction To Soil Life And Its Role In Profitable Grazing Systems, Ray Archuleta

Kentucky Grazing Conference

No abstract provided.


Mgrre_Thinsections_05_A_62, Mgrre Oct 2022

Mgrre_Thinsections_05_A_62, Mgrre

Thin Sections

No abstract provided.


Flow Regime Evolution Of A Major Cave System In The Eastern Alps (Hirlatzhöhle, Dachstein), Lukas Plan, Gottfried Buchegger, Eva Kaminsky, Gabriella Koltai, Tanguy Racine, Jacek Szczygieł Oct 2022

Flow Regime Evolution Of A Major Cave System In The Eastern Alps (Hirlatzhöhle, Dachstein), Lukas Plan, Gottfried Buchegger, Eva Kaminsky, Gabriella Koltai, Tanguy Racine, Jacek Szczygieł

International Journal of Speleology

The 116 km-long and 1560 m-deep Hirlatzhöhle is one of the major cave systems in the Northern Calcareous Alps (NCA; Austria). It is located in the NW part of the Dachstein, an extensive karst massif encompassing 576 km² with its highest point at 2995 m a.s.l. In contrast to most other caves in the NCA, Hirlatzhöhle comprises old (epi)phreatic passages located up to 1 km above the base level as well as two modern major drainage systems. The aim of this study is to define the palaeo- and the active flow conditions in combination with speleogenesis, and the age of …


Study On Mechanical Mechanism Of Roof Fracture Evolution In Deep Stope With Variable Face Length, Wang Xinfeng, Lu Mingyuan Oct 2022

Study On Mechanical Mechanism Of Roof Fracture Evolution In Deep Stope With Variable Face Length, Wang Xinfeng, Lu Mingyuan

Coal Geology & Exploration

Irregular coal seam mining is easy to cause the problems such as roof stress concentration and abnormal ground pressure behavior. In order to explore the roof fracture law and the structural evolution characteristics of stope with variable length, the roof structure models with four types of boundary conditions were established and analyzed using the small-deflection thin plate bending theory in view of the geometric characteristics and mechanical causes of the abrupt stope with the inclined length of working face changing from small to large in various mining stages. Meanwhile, the roof fracture law and macro-mechanical response were analyzed by MATLAB …


Research On Permeability Model Of Coal Reservoir Along Producing Wellbores, Jia Lidan, Zhang Lin, Li Bobo, Wu Xuehai, Gao Zheng, Wang Zhonghui, Fu Jiale Oct 2022

Research On Permeability Model Of Coal Reservoir Along Producing Wellbores, Jia Lidan, Zhang Lin, Li Bobo, Wu Xuehai, Gao Zheng, Wang Zhonghui, Fu Jiale

Coal Geology & Exploration

Permeability is an important parameter to characterize gas flow. In order to ensure the safe and efficient gas drainage, it is necessary to explore the evolution characteristics of coal reservoir gas seepage at different positions from the producing wellbores. However, the effective stress, the gas adsorption/desorption capacity of coal matrix and the temperature of coal reservoir are constantly changing with the gas drainage, and even the drainage damage may occur, which makes the gas migration behavior in coal seam extremely complicated. In order to explore the seepage characteristics of coal reservoir gas during gas drainage, the space-time evolution function of …


Research And Application Progress Of Energy Underground Structures, Wen Jiwei, Hou Junlong, Liu Xinghong, Zeng Xian’En, Xiang Tian Oct 2022

Research And Application Progress Of Energy Underground Structures, Wen Jiwei, Hou Junlong, Liu Xinghong, Zeng Xian’En, Xiang Tian

Coal Geology & Exploration

Energy geostructure refers to a type of structure equipped with heat exchange pipe in the building foundation element and the underground structure, which has the functions of load bearing and heat exchange. It not only effectively saves the valuable and irreversible underground space resources, but also makes full use of the non-carbon based continuous, stable, safe and clean geothermal energy resources, thus having more advantages than the traditional Ground Source Heat Pump (GSHP). Herein, the concept, advantages, research and application progress of energy geostructure at home and abroad were systematically summarized. Moreover, the current situation of four common energy geostructures, …


Numerical Simulation Of The Influence Of Karst Structure On Heat Transfer Efficiency Of Buried Pipeline Group, Mu Xuan, Pei Peng, Zhou Xin, Tu Hongsheng Oct 2022

Numerical Simulation Of The Influence Of Karst Structure On Heat Transfer Efficiency Of Buried Pipeline Group, Mu Xuan, Pei Peng, Zhou Xin, Tu Hongsheng

Coal Geology & Exploration

The buried pipeline is the part where the rock mass heat pump system performs direct heat transfer with the ground. The water-bearing structure in the karst area is complex and diverse, which has a significant impact on the heat transfer and storage of the buried pipeline group. Herein, the heat transfer process of a group of 27 vertical buried pipelines in four geological structure types was simulated, including the non-karst structure, fractured karst structure, karst conduit structure and mixed karst structure. Meanwhile, comparison was made for the change of parameters, such as the temperature field in the rock mass, the …