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Articles 2281 - 2310 of 59520
Full-Text Articles in Earth Sciences
Mechanisms Behind Soil Water Evaporation And Infiltration During Long-Term Microbial Reclamation In Coal Mining-Induced Subsidence Areas In Northern Shaanxi Province, China, Ke Zengming, Bi Yinli, Yang Wei
Mechanisms Behind Soil Water Evaporation And Infiltration During Long-Term Microbial Reclamation In Coal Mining-Induced Subsidence Areas In Northern Shaanxi Province, China, Ke Zengming, Bi Yinli, Yang Wei
Coal Geology & Exploration
Background Water scarcity is identified as an important factor restricting ecological restoration in arid and semi-arid mining areas. The application of microbial reclamation technologies, especially inoculation with Arbuscular mycorrhizal fungi (AMF), has achieved encouraging ecological effects in mining areas. In this case, investigating soil water movement and its controlling factors in mining areas undergoing long-term microbial reclamation is a key scientific issue for understanding the long-term ecological restoration mechanisms of AMF. Methods This study investigated the microbial reclamation base in the coal mining-induced subsidence area of the Daliuta coal mine of northern Shaanxi Province, located in the middle reaches of …
Water Quality Characteristics And Reutilization Of Goaf Water From Shallow Coal Seams Within The Datong Mining Area, Shanxi Province, China, Li Jun, Gui Herong, Ding Pengfei, Chen Yongqing, Wan Heyong, Li Weiqi, Huang Dawei, Peng Weihua, Hu Yang, Guo Yan
Water Quality Characteristics And Reutilization Of Goaf Water From Shallow Coal Seams Within The Datong Mining Area, Shanxi Province, China, Li Jun, Gui Herong, Ding Pengfei, Chen Yongqing, Wan Heyong, Li Weiqi, Huang Dawei, Peng Weihua, Hu Yang, Guo Yan
Coal Geology & Exploration
Objective The Datong mining area in Shanxi Province of China faces serious threats from goaf water hazards, while the goaf water drainage is constrained by environmental protection policies. Therefore, the reutilization of goaf water serves as an effective approach to eliminating mine water hazards, protecting water environments, and mitigating water scarcity in the mining area. Methods This study investigated goaf water from shallow coal seams in the Datong mining area. Based on water quality assessment theories and a range of hydrogeochemical indices, including saturation index (SI), chloro-alkaline index (CAI), and sodium adsorption ratio (SAR), this study conducted a joint determination …
Advances In Research And Future Prospects Of Borehole Geophysical Prospecting Technology For Coal Mines, Li Ping, Wei Rong, Fan Tao, Zhao Rui, Jiang Bici, Tian Xiaochao, Wang Bingchun
Advances In Research And Future Prospects Of Borehole Geophysical Prospecting Technology For Coal Mines, Li Ping, Wei Rong, Fan Tao, Zhao Rui, Jiang Bici, Tian Xiaochao, Wang Bingchun
Coal Geology & Exploration
Background Borehole geophysical prospecting technology for coal mines integrates the advantages of both drilling and geophysical prospecting. Accordingly, multiple critical advances have been achieved in its applications to the technologies and equipment for intelligent coal mining in recent years, enabling long-distance, relatively high-precision geological exploration. This technology plays an increasingly important role in a range of fields, including deep mineral resource exploration and the reconnaissance surveys of hidden disaster-causing factors, providing robust support for safe and efficient coal mining. Advances This study systematically reviews the development history of borehole geophysical prospecting technology, elaborating advances in research on the methodology, theories, …
Application Of Seismic-While-Tunnelling Detection In The Identification Of Densely Distributed Sub-Seismic Faults, Li Haodang, Li Kang, Chen Jian, Song Xiaozhong, Jin Dan, Wang Baoli
Application Of Seismic-While-Tunnelling Detection In The Identification Of Densely Distributed Sub-Seismic Faults, Li Haodang, Li Kang, Chen Jian, Song Xiaozhong, Jin Dan, Wang Baoli
Coal Geology & Exploration
Objective and Method Densely distributed sub-seismic faults have emerged as a major hidden disaster-causing geological factor, heavily influencing both the production efficiency and operational safety of coal mines. To achieve precise advance detection of underground sub-seismic faults in coal mines, this study designed a geological model. Using seismic-while-tunneling (SWT) advance detection technology for roadways of coal mines, this study investigated the geological situation of sub-seismic faults through forward modeling. Furthermore, it explored the seismic image characteristics of these faults obtained using the SWT observation system under varying survey line lengths and geophone spacing values. Results and Conclusions The forward modeling …
Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni
Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni
Tanzania Journal of Science
In response to the ongoing challenges posed by the scarcity of reliable fresh-water sources in Lukobe Ward, Morogoro Municipality, Tanzania, this study applied an integrated approach that combines geospatial and geophysical datasets to identify previously undocumented aquifers. The datasets utilized include an apparent density map generated from high-resolution GGMPlus satellite gravity data, a geological map (Quarter Degree Sheet 183), a water drainage map, and a slope map created from a digital elevation model (DEM). The analysis successfully identified four unconfined, saprolitic aquifers in the study area, designated as aquifers A, B, C, and D. These aquifers span areas of 12.2 …
Fast Dispersion-Curve Inversion Using Automatic Differentiation Gradient-Based Calculation, Theodosius Marwan Irnaka, Eddy Hartantyo
Fast Dispersion-Curve Inversion Using Automatic Differentiation Gradient-Based Calculation, Theodosius Marwan Irnaka, Eddy Hartantyo
Makara Journal of Science
Surface wave inversion is a crucial technique in geophysics for subsurface imaging. However, traditional methods can be computationally intensive, especially for complex models. This study introduces automatic differentiation (AD) as an efficient alternative to finite difference (FD) methods for gradient calculation in surface wave inversion. We compare AD and FD methods using three synthetic examples of varying complexity. Our results demonstrate that AD is significantly faster, with speed improvements of 3 to 12 times over FD, depending on model complexity. Moreover, AD requires up to 3 times less memory than FD. In terms of accuracy, AD provides gradient calculations that …
A Cave In Miocene Conglomerate: The Törökpince-Abaliget Cave System, Hungary, Krisztina Sebe, Piroska Pazonyi, Márton Bauer, Bálint Szappanos, Márton Szabó, Zoltán Szentesi, Mihály Gasparik, Ákos Juhász, Luca Pandolfi, Máté Gregorits, József Haász, Ágnes Novothny, Zsófia Ruszkiczay-Rüdiger
A Cave In Miocene Conglomerate: The Törökpince-Abaliget Cave System, Hungary, Krisztina Sebe, Piroska Pazonyi, Márton Bauer, Bálint Szappanos, Márton Szabó, Zoltán Szentesi, Mihály Gasparik, Ákos Juhász, Luca Pandolfi, Máté Gregorits, József Haász, Ágnes Novothny, Zsófia Ruszkiczay-Rüdiger
International Journal of Speleology
Conglomerate caves are rare, and only a few have been described in the scientific literature. Here, we present a newly discovered and significant cave system in SW Hungary, comprising over 500 m of upper passages and a shorter, lower section of a through-cave developed in Lower–Middle Miocene conglomerates. The formation of these cave passages was controlled chiefly by bedding and fractures. Dissolution has produced typical karstification morphologies, whereas corrasion, granular disintegration, and rock collapse have also played a role in shaping the cave. The cave is dominated by vadose-zone morphologies, but sediment infills indicating upward water flow, along with ceiling …
Macroinvertebrate Community Dynamics In A Recovering, Hypersaline Estuary, Catherine M. Eckert, Claudia A. Tamez, Erin E. Easton, David Hicks
Macroinvertebrate Community Dynamics In A Recovering, Hypersaline Estuary, Catherine M. Eckert, Claudia A. Tamez, Erin E. Easton, David Hicks
School of Earth, Environmental, & Marine Sciences Faculty Publications
The Bahia Grande is a 6,500—acre tidal basin located at the southernmost tip of Texas. Tidal flow into this coastal estuary was cut off in the 1930s, causing the basin to dry up for ~70 y. A pilot channel connecting the Bahia Grande to tidal waters was constructed in 2005, allowing flooding of the basin to occur. Throughout the period reported herein (2005–2019), the system remained characterized by persistent spatial and temporal episodes of extreme hypersalinity (>70)—a critical factor influencing estuarine community composition and driving key ecological processes. With additional rehabilitation actions forthcoming, characterization of the estuary is essential …
What Does Graptolite Origination And Extinction Reveal About The Cause Of The Late Ordovician Mass Extinction?, Charles E. Mitchell, H. David Sheets, Michael J. Melchin, Chris Holmden
What Does Graptolite Origination And Extinction Reveal About The Cause Of The Late Ordovician Mass Extinction?, Charles E. Mitchell, H. David Sheets, Michael J. Melchin, Chris Holmden
Computer and Data Science Faculty Publications
Assesses the macroevolutionary turnover of paleotropical planktic graptolites during the Late Ordovician Mass Extinction (LOME) via automated sequencing and capture-mark-recapture modeling. Graptolites exhibited a succession of turnover pulses (sensu Elizabeth Vrba) that were coincident with the main phases of the Hirnantian glaciation and during which the Diplograptina experienced declining metapopulation size, elevated extinction, zero species originations, and ultimately, complete extermination. Concurrently, the Neograptina (latest Katian temperate zone immigrants) exhibit pulses of both extinction and adaptive radiation. Thus, the LOME involved intense species selection and the wholesale alteration of the clade diversity structure of a major element of the zooplankton. The …
Linking Shoreline Change, Environmental Forcings, And Sedimentological Resilience In Nourished Beaches Of Cape May And Wildwood, New Jersey, Usa: A Multi-Decadal Synthesis, Divomi Balasuriya, Greg Pope
Linking Shoreline Change, Environmental Forcings, And Sedimentological Resilience In Nourished Beaches Of Cape May And Wildwood, New Jersey, Usa: A Multi-Decadal Synthesis, Divomi Balasuriya, Greg Pope
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Beach nourishment is a widely used strategy to mitigate coastal erosion, yet its long-term geological impacts remain poorly understood. This study provides a multi-decadal synthesis of shoreline change and sedimentological evolution on the nourished beaches of Cape May and Wildwood, New Jersey, USA. Using shoreline positions from 1991 to 2024, we identify contrasting trajectories: Wildwood exhibits ‘persistent transition’ with severe northern erosion (EPR: −10.0 m/yr) feeding southwards accretion, while Cape May demonstrates a ‘managed equilibrium’ with widespread accretion (mean EPR: +1.15 m/yr). Wave energy correlations account for less than 15% of shoreline variability, indicating natural drivers have been superseded by …
First-Principles Insights Into Binary Oxide Systems Under Extreme Pressure, Daniel Schacher
First-Principles Insights Into Binary Oxide Systems Under Extreme Pressure, Daniel Schacher
UNLV Theses, Dissertations, Professional Papers, and Capstones
Pressure is powerful tool by which one can manipulate the properties of materials. In this work we utilize pressure to explore binary oxide systems and characterize their structural and electronic properties. The observation of anomalous structural and electronic behavior in the rutile to CaCl2 phase transition in SnO2 led to the prediction that such behavior is inherent to all oxides experiencing such a phase transition sequence.[1] Here, the ultra-wide band gap semiconductor GeO2 is confirmed to exhibit anomalous behavior during the rutile to CaCl2 phase transition. A phase pure rutile GeO2 sample synthesized under high-pressure, high-temperature, conditions is probed using …
Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev
Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev
Honors Scholar Theses
This work applies the Lyapunov method to identify instabilities and compute the growth rate of a linear time-varying system. The linear system studied describes cold fresh water on top of hot salty water with a periodically time-varying background shear flow. A time-dependent weighting matrix is employed to construct a Lyapunov function candidate. The resulting linear matrix inequalities are discretized in time using the forward Euler method. As the number of temporal discretization points increases, the growth rate predicted by the Lyapunov method or Floquet theory, used for comparison, will converge to the same value obtained from numerical simulations. Furthermore, the …
Quantifying Biocrust Evaporation In Arid Lands By Combining Thermal Imaging And Lysimeter Measurements, Rebekah C. Magness
Quantifying Biocrust Evaporation In Arid Lands By Combining Thermal Imaging And Lysimeter Measurements, Rebekah C. Magness
UNLV Theses, Dissertations, Professional Papers, and Capstones
Biological soil crusts (biocrusts) are miniature ecosystems of living organisms incorporated within the soil matrix and established in the topmost millimeters of the soil surface. Biocrust plays a critical role in the hydrologic processes in arid lands, yet the extent to which it increases or decreases evaporation remains unclear. To gain a better understanding of the impact of biocrust on evaporation compared to bare soil, I studied a cyanobacteria-dominated biocrust patch surrounded by bare soil atop a lysimeter in the Mojave Desert near Las Vegas, Nevada. Using high-resolution thermal imaging, and the known latent heat flux from the lysimeter, I …
Towards Spatial Inversion Of Aerial Gamma-Ray Survey Data For Measurement Of Naturally Occurring Radioactivity, Daniel A. Haber
Towards Spatial Inversion Of Aerial Gamma-Ray Survey Data For Measurement Of Naturally Occurring Radioactivity, Daniel A. Haber
UNLV Theses, Dissertations, Professional Papers, and Capstones
Aerial gamma-ray surveying (AGRS) is used in geologic and environmental contexts to provide data on the surface spatial distribution of naturally occurring radioactive material (NORM) or other gamma-ray-emitting isotopes. The standard data reduction workflow for AGRS data involves a process whereby pointwise gamma-ray spectral data are denoised, corrected for numerous sources of background radiation and aircraft height, and are finally converted to physical values by empirical conversion factors. The reduced pointwise data are then typically spatially interpolated to form a continuous surface map.
This dissertation introduces and explores a novel spatial inversion method for reduced AGRS data that considers aircraft …
Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia
Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia
UNLV Theses, Dissertations, Professional Papers, and Capstones
Tropical monsoon rainfall is a key component of Earth’s climate system and supports the livelihood and economy of billions of people. Yet, projections of future monsoons remain highly uncertain, particularly in regions with distinct physiography and complex land-ocean-atmosphere interactions like Central America, where long and continuous high-resolution paleoclimate data to test climate model simulations are still limited. This series of studies aims to reconstruct monsoon dynamics and underlying forcing controls in Central America on multiple timescales by the analysis and integration of stable isotope data in modern and paleo-rainfall records from Guatemala.
In Chapter 2, I present a daily-resolution, two-year-long …
Fault Structure, Deformation Mechanisms, And Why Fault Zones Matter To Society, Elizabeth S. Petrie, David A. Ferrill, Kelly K. Bradbury, James P. Evans
Fault Structure, Deformation Mechanisms, And Why Fault Zones Matter To Society, Elizabeth S. Petrie, David A. Ferrill, Kelly K. Bradbury, James P. Evans
Geosciences Faculty Publications
Faults are widespread geologic structures that form in sediment and all rock types, occur in all tectonic regimes, and can be a blessing or a curse to society. Faults and fault zones act as conduits for underground movement of water and as plumbing systems for aquifers and springs essential for human habitation in many semi-arid and arid regions worldwide. Faults also provide pathways for natural oil and gas migration and high-permeability zones in hydrocarbon reservoirs, as well as barriers contributing to trapping and reservoir compartmentalization. By enhancing permeability in many geothermal energy systems, faults can be essential for fluid circulation …
The Effect Of Phosphate Fertilizer And Organic Matter On Phosphorus Status, Ph, And Cabbage Yield In Andisols, Mahfud Arifin, Emma Trinurani Sofyan, Anni Yuniarti, Rina Devnita, Sastrika Anindita
The Effect Of Phosphate Fertilizer And Organic Matter On Phosphorus Status, Ph, And Cabbage Yield In Andisols, Mahfud Arifin, Emma Trinurani Sofyan, Anni Yuniarti, Rina Devnita, Sastrika Anindita
Jurnal Kultivasi
Andisols are characterized by high phosphorus (P) retention, which often limits P availability for crops. This study aimed to analyze the independent and interactive effects of P fertilizer and organic matter (i.e. manure and rice straw compost) on P retention, total P, available P, P uptake, soil pH, and cabbage yield. This research was conducted in pot experiments in plastic house, applying P fertilizer (0, 90, 180, 270 kg ha-1) and organic matter (20 kg ha-1 of chicken, sheep, cow manures and rice straw compost) on Andisols planted with cabbage. The experiment used a factorial randomized design. The results showed …
Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason
Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason
Earth and Planetary Sciences ETDs
Both historical and contemporary evidence for geomorphic activity on the surface of Mars is apparent. This evidence is showcased by features including a) well-preserved deltaic remnants in an otherwise cold and arid environment, present along the western flank of Jezero Crater, and b) the seasonal appearance of candidate recurring slope lineae throughout Martian equatorial, lower, and mid-latitudes as seen within both the Eos Chasma region and on the walls of Raga, Lohse, Rauna, and Tivat Craters. In this dissertation, I elucidate the role that geomorphic processes, whether aqueous or dry, have played in shaping both the ancient and contemporary Martian …
Dense Temporary Array Investigation Of Jemez Uplift Seismicity, Jillian D. Podmore
Dense Temporary Array Investigation Of Jemez Uplift Seismicity, Jillian D. Podmore
Earth and Planetary Sciences ETDs
A protracted multi-stage tectonic and magmatic evolution combined with low regional crustal strain rates make it challenging to characterize active structure that may host earthquakes in the Jemez Mountains of New Mexico. Here, we leverage temporary 1-month deployments of nodal seismometers to gain new insights into seismicity of the Jemez Mountains, which only have continuous seismic monitoring on their eastern flank as a result of the Los Alamos Seismic Network. Our catalog is built using 4 steps: phase picking in continuous seismic data, association of picks to detect unique events, event magnitude estimation, and absolute hypocenter estimation. We detect and …
Seismological Investigations Of Magmatic Systems Using Dense Nodal Arrays, Wenkai Song
Seismological Investigations Of Magmatic Systems Using Dense Nodal Arrays, Wenkai Song
Earth and Planetary Sciences ETDs
Understanding the internal architecture of magmatic systems is crucial for volcanology, yet conventional geophysical techniques often lack the resolution to image their fine-scale structures. This dissertation leverages unique datasets from dense nodal arrays to investigate the upper crustal magmatic systems beneath Yellowstone Caldera, Valles Caldera, and Mount St. Helens. At Yellowstone, I processed vibroseis data to delineate the top of the modern magma reservoir and evaluate the thermal connection between the magmatic and the overlying hydrothermal systems. At Valles, 3D radial seismic anisotropy imaging reveals strong positive radial anisotropy within the reservoir, indicating an organized structure of horizontally sill-like melt …
Microbial Metabolism Amplified Warming In Three Phanerozoic Hyperthermal Events, Yuyang Wu, Haijun Song, Daoliang Chu, Ying Cui, Jacopo Dal Corso, Genming Luo, Huyue Song, Li Tian, Hanchen Song, Enhao Jia, Jinnan Tong
Microbial Metabolism Amplified Warming In Three Phanerozoic Hyperthermal Events, Yuyang Wu, Haijun Song, Daoliang Chu, Ying Cui, Jacopo Dal Corso, Genming Luo, Huyue Song, Li Tian, Hanchen Song, Enhao Jia, Jinnan Tong
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The ocean’s biological carbon pump (BCP) plays a crucial role in climate regulation by facilitating long-term removal of atmospheric CO2. However, BCP changes during past hyperthermals remain poorly understood. Here we use the vertical carbon isotope (δ13C) gradients between surface and mid-waters to trace the BCP changes during the Permian−Triassic, early Toarcian, and Palaeocene−Eocene hyperthermals, detecting a two- to three-fold increase in the vertical δ13C gradients. We found that enhanced organic matter remineralization, driven by increased microbial respiration under warming, are the primary trigger for increased vertical δ13C gradients. Warming-induced enhancements in microbial metabolism caused a two- to six-fold reduction …
Flooding Behavior Near The Us/Canada Border: Complications And Approaches, Maria T. Dodson
Flooding Behavior Near The Us/Canada Border: Complications And Approaches, Maria T. Dodson
Honors College Theses
Flood forecasting remains a major challenge due to the nonlinear nature of hydrological systems and uncertainties in environmental data. This study aimed to address the prevalent challenges that arise from forecasting flooding behavior. To address the inherent complexity of hydrological forecasting, a machine learning framework was developed and trained on major contributing factors. To achieve an optimal balance between computational efficiency and predictive performance, a Gated Recurrent Unit (GRU) was selected as the optimal machine learning model. As the chosen dataset, North American Land Data Assimilation System Phase 2 (NLDAS2), is known to have inaccuracies in the important feature Relative …
Mississippi River Pre-Loess Terrace Deposits: Distribution Of Aggregate Resources, Jonathan Leard
Mississippi River Pre-Loess Terrace Deposits: Distribution Of Aggregate Resources, Jonathan Leard
Theses and Dissertations
Pre-loess Terrace Deposits are a Pleistocene, high-quality aggregate resource of gravel, sand, and clay subjacent to loess of varying thickness along the eastern valley wall of the Yazoo Basin in Mississippi. This project delineated 1,230 mi2 of this resource with a volume greater than 33 billion yd3 from the misinterpreted Citronelle Formation in Desoto, Tate, Marshall, Panola, Tallahatchie, Yalobusha, Grenada, Carroll, Holmes, Yazoo, Madison, Hinds, Warren, Jefferson, Claiborne, Adams, Franklin, and Wilkinson Counties with nine terrace base levels at 40, 180, 220, 250, 270, 300, 330, 340, and 370 feet msl indicated by test holes, gravel mine data, outcrop studies, …
The Effects Of Nanobubble Fertigation And Soil Conditioners To Improve Nutrient Dynamics, Soil Microbial Activity, And Chili Productivity, Betty Natalie Fitriatin, Euis Ahah Rokayah, Elsa Naila Elmyra, Tualar Simarmata, Nicky Oktav Fauziah, Hanif Fakhrurroja
The Effects Of Nanobubble Fertigation And Soil Conditioners To Improve Nutrient Dynamics, Soil Microbial Activity, And Chili Productivity, Betty Natalie Fitriatin, Euis Ahah Rokayah, Elsa Naila Elmyra, Tualar Simarmata, Nicky Oktav Fauziah, Hanif Fakhrurroja
Jurnal Kultivasi
Drip fertigation is a fertilization method that integrates nutrient delivery with an irrigation system, which is capable of optimizing the direct delivery of nutrients to the root zone. This experiment aims to investigate the effect of drip fertigation with nanobubble technology, and soil conditioners on the population of Phosphate-Solubilizing Bacteria (PSB) and Azotobacter spp., available phosphorus, total nitrogen, growth, and yield of red chili. The study used a Strip Plot Design with two factors and three replications. The first factor was nutrient application (solid NPK fertilizing as control; drip fertigation; and drip fertigation with nanobubble technology), and the second factor …
Measurements Of Water-Film Thickness On Cave Walls And Speleothems, Alexandre Honiat, Salaheddine Skali-Lami, François Bourges, Bruno Lartiges
Measurements Of Water-Film Thickness On Cave Walls And Speleothems, Alexandre Honiat, Salaheddine Skali-Lami, François Bourges, Bruno Lartiges
International Journal of Speleology
The water-film that coats cave walls and speleothems is a key player for the regulation of cave microclimate and the control of speleothem growth. In this paper, we demonstrate the capability of a confocal optical sensor to quantitatively measure on-site the rapid variations of water-film thickness when dripping, active condensation, or dryness occur on walls of various caves. Results obtained from a sample of four prehistoric caves and one stalagmite cave from Southwest France, indicate that the measurable thickness of water-films is generally in the 25-70 µm range for cave walls and reaches 200-300 µm on the horizontal plane of …
A Sedimentary Source Of Rare Earth Elements In The North Atlantic, Rylee D. Lindner
A Sedimentary Source Of Rare Earth Elements In The North Atlantic, Rylee D. Lindner
Electronic Theses and Dissertations
Individually and as a series, the Rare Earth Elements (REEs) are powerful geochemical tracers of environmental processes. However, ambiguities in the oceanic budgets of the REEs hamper their application. Growing evidence suggests a sedimentary benthic flux via the pore water is the major source of REEs to the ocean, with extrapolated estimates of this flux being equivalent in magnitude to that “missing” from modern budgets. However, existing pore water REE data are available from only a few locations globally with no representative dataset from the open North Atlantic. This data scarcity limits our ability to constrain flux estimates and understand …
Collaborative Research: Evolution Of The Tristan-Gough-Walvis Ridge Hotspot System: Age And Composition Of Expedition 391/397t Volcanic Basement, Katherine Elizabeth Potter
Collaborative Research: Evolution Of The Tristan-Gough-Walvis Ridge Hotspot System: Age And Composition Of Expedition 391/397t Volcanic Basement, Katherine Elizabeth Potter
Funded Research Records
No abstract provided.
Collaborative Research: Rapid: Fault Rupture And Spring Sampling Of The 2023 Kahramanmaras, Turkey, Earthquake Sequence Ruptures, Alexis Ault, Dennis Lowell Newell
Collaborative Research: Rapid: Fault Rupture And Spring Sampling Of The 2023 Kahramanmaras, Turkey, Earthquake Sequence Ruptures, Alexis Ault, Dennis Lowell Newell
Funded Research Records
No abstract provided.
Stream Behavior Characterization Of Marin County Coastal Watersheds And Their Influence On Salmonid Habitat, Ellie L. Murdoch
Stream Behavior Characterization Of Marin County Coastal Watersheds And Their Influence On Salmonid Habitat, Ellie L. Murdoch
Master's Theses
Coastal watersheds in California are increasingly affected by climatic variability, threatening stream behavior, ecological function, and salmonid habitat suitability. This study evaluated streamflow behavior of seven watersheds in Marin County, California, with detailed analysis of Corte Madera, Olema, and Redwood watersheds, which are not influenced by reservoir releases. Using USGS stream gauge records, PRISM climate data, SSURGO soils, and geologic and vegetation information, streamflow metrics critical to salmonid life cycles were quantified for water years 2014 to 2023. Watersheds with greater storage capacity, such as Redwood, exhibited muted hydrologic responses, including delayed flow activation, lower peak flows, slower recession rates, …
A Study Of The Stratigraphic And Petrological Characteristics Of Section (10,323-10,325 Ft), Prevost 1- 11, Bay County, Michigan, Hajir Al Harthi
A Study Of The Stratigraphic And Petrological Characteristics Of Section (10,323-10,325 Ft), Prevost 1- 11, Bay County, Michigan, Hajir Al Harthi
Honors Theses
This study presents a detailed petrological characterization of a short core section (10,323-10,325 ft) from the Prevost 1-11, Bay County, Michigan. This work is part of a broader carbon capture, utilization, and storage (CCUS) project to determine whether the Glenwood Formation could be an effective confining unit (CU) for carbon dioxide (CO2) injection in the underlying St. Peter Sandstone. The methods used to collect petrological data include standard core description, Xray fluorescence spectroscopy (XRF), powder X-ray diffraction (XRD), thin section microscopy, and scanning electron microscopy (SEM) including backscattered electron (BSE), energydispersive X-ray spectroscopy (EDS), and secondary electron (SE) modes. These …