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Articles 20941 - 20970 of 29947
Full-Text Articles in Geology
Assessing Grassed Waterway Implementation Using Acpf And Swat Models, Kirsten Schaefer
Assessing Grassed Waterway Implementation Using Acpf And Swat Models, Kirsten Schaefer
Graduate Theses/Dissertations
Agriculture is the most significant contributor of nonpoint source pollutants in US waterways, with sediment being the most prevalent cause of impairments. Sediment loss mitigation occurs through Best Management Practices (BMPs), such as grassed waterways. Federal and state agencies incentivize the implementation of BMPs through cost-share programs for farmers. The investment of public funds has increased pressure to demonstrate the effectiveness and value of individual projects, necessitating the development of strategies for prioritizing projects based on the sensitivity of sites to sediment erosion and optimal locations for implementation. This study has three primary objectives: (i) document existing locations of grassed …
Constraining Respired Carbon Storage In The Eastern Tropical Pacific Over The Last 25 Thousand Years Using Benthic Foraminiferal Boron/Calcium Ratios, Brian James Close
Constraining Respired Carbon Storage In The Eastern Tropical Pacific Over The Last 25 Thousand Years Using Benthic Foraminiferal Boron/Calcium Ratios, Brian James Close
OES Theses and Dissertations
The storage of inorganic carbon in the deep Pacific Ocean is thought to play an important role in regulating both glacial-interglacial and millennial-scale atmospheric CO2 concentrations (Broecker and Barker 2007; Sigman et al., 2010). A recent study by Loveley et al. (2017) showed that sedimentary authigenic uranium (aU) concentrations, a proxy for suboxic bottom-water conditions, increased significantly in the Eastern Equatorial Pacific (EEP) during the Last Glacial Maximum (LGM, 18 kyr – 23 kyr). If this is correct, the low-oxygen, CO2-rich waters would also have a lower pH and a lower carbonate ion concentration ([CO32- …
Pre-Eruptive Evolution Of Izu-Bonin Boninite Melts: Mixing, Cooling, And Crystallization, Jesse L. Scholpp
Pre-Eruptive Evolution Of Izu-Bonin Boninite Melts: Mixing, Cooling, And Crystallization, Jesse L. Scholpp
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Subduction is the geologic process in which one tectonic plate moves beneath another as it sinks into the Earth’s mantle. Subduction initiation in the Izu-Bonin Marianas system is the result of a gravitational failure during which one tectonic plate (the Pacific plate) spontaneously sinks beneath another (the Philippne Sea plate). Fluids released by the sinking plate that caused the overlying mantle to melt by reducing its meltimg temperature, forming the Izu-Bonin Mariana island arc system.
The resulting melts initially have the chemical compositions that are rich in silica and magnesia, and highly depleted in other elements, refered to a boninite …
Investigating The Timing Of Initial Louann Salt Flow And Its Relationship With The Gilbertown Fault Zone, Southwest Alabama, Avery Rosenbalm
Investigating The Timing Of Initial Louann Salt Flow And Its Relationship With The Gilbertown Fault Zone, Southwest Alabama, Avery Rosenbalm
Master's Theses
The Mesozoic Louann Salt extends through the northern GOM, extending onshore from eastern Texas to western Alabama and Florida. Along the landward terminus of the salt is a system of peripheral faults, including the Gilbertown Fault Zone bordering the Mississippi Interior Salt Basin to the north and east. This study sought to constrain the timing of fault movement and determine its relationship to the baswinward evacuation of Louann Salt through the use of a 3D seismic survey and well logs. By mapping Mesozoic formations and the peripheral fault system, lateral changes in formation thickness were used to generate fault expansion …
Assessing The Recalibration Interval For Nearshore Sediment Assemblages After Hurricane Irma: Implications For Developing Long-Term Records Of Overwash Deposits, Stephen Mitchell
Assessing The Recalibration Interval For Nearshore Sediment Assemblages After Hurricane Irma: Implications For Developing Long-Term Records Of Overwash Deposits, Stephen Mitchell
Master's Theses
Surface distributions are commonly collected to assist with overwash interpretation; however, many of these are first established immediately after a major overwash event as part of a post-event field survey. This study documents the impacts of Hurricane Irma, a Category 5 storm, on nearshore sediments off the coast of Anegada (British Virgin Islands) using distributions of Homotrema rubra, an encrusting foraminifer with a defined provenance in coral reef ecosystems. Over four sampling intervals spanning 2 years, from six months pre-Hurricane Irma to 18 months post-Hurricane Irma, surface sediment was collected from three shore-perpendicular transects on both the northern and …
Sediment Provenance Of Tsunami Deposits: Implications For Assessing The Relative Intensity Of Paleotsunamis From The Sendai Coastline Of Japan, Tiffany Otai
Master's Theses
The 2011 Tohoku tsunami impacted the northeastern coast of Japan and caused unexpected damages due to the underestimation of this type of hazard. Of particular importance is the fact that geologic evidence for a predecessor event, the Jogan tsunami (CE 869), could have forecasted the severity of the 2011 Tohoku event. While the timing of tsunamis is important for effective hazard mitigation, outside of the 2011 Tohoku event, the intensity of past tsunamis remains unclear. To understand paleotsunami intensity, it is important to document characteristics of modern analogues like the 2011 event. This study utilizes surface distributions of foraminifera from …
Monitoring Salt Diapir Related Land Deformation And Distribution: A Geophysical And Remote Sensing Approach Jazan Province, Saudi Arabia, Hannah G. Pankratz
Monitoring Salt Diapir Related Land Deformation And Distribution: A Geophysical And Remote Sensing Approach Jazan Province, Saudi Arabia, Hannah G. Pankratz
Dissertations
Salt diapirs are rarely preserved on the surface and seldom considered as environmental hazards. The Jazan city diapir (JZD) is located in southwest Saudi Arabia along the Red Sea coastal plain and outcrops in the middle of a rapidly growing port city. The intrusion of the diapir (~ 2 km2) into the overburden sediments continues to cause uneven surfaces, compromises building foundations and infrastructure, caused dissolution sinkholes, and limits the expansion of the city along the coastline. This research aims to better understand the distribution and deformation associated with salt diapirs in arid environments.
Using integrated Interferometric Synthetic …
Framework Grain Composition And Texture Of The Wedington Sandstone Member, Fayetteville Shale, As A Provenance And Sediment Dispersal Indicator For Clastic Depositional Systems Across The Northern Arkansas Structural Platform During The Late Mississippian, Tanner Wayne Corbin
Graduate Theses and Dissertations
The Wedington Sandstone Member of the Fayetteville Shale is a constructive delta complex in the Chesterian section of the Late Mississippian record in Northwest Arkansas. A comparative analysis of framework grain composition between the Wedington and two other stratigraphically proximal Carboniferous sandstones: the Batesville Sandstone (older) and the Basal Atoka-Spiro Sandstone (younger) has addressed three questions: 1) Is there similarity in sediment provenance for the three sandstones? 2) Do these three sandstone units have a similar sediment dispersal vector? 3) What are likely sediment source terrains for the Wedington Sandstone? Wedington samples overwhelmingly plot as quartzarenites with fewer samples plotting …
Multi-Proxy Provenance Evaluation Of The Stevens Sandstone, San Joaquin Basin, California, Charles Adam Ball
Multi-Proxy Provenance Evaluation Of The Stevens Sandstone, San Joaquin Basin, California, Charles Adam Ball
Graduate Theses and Dissertations
The Stevens sandstone is a prolific hydrocarbon reservoir in the southern San Joaquin Basin that has produced greater than five billion barrels of oil equivalent and represents an important exploration target. The San Joaquin basin has a complex depositional and structural history related to the overprinting of a Mesozoic-Paleogene forearc basin by transtension and transpression along the San Andreas fault system that presently borders the southwestern side of the basin. The Stevens sandstone consists of quartzo-feldspathic, deep-water turbidite deposits and is primarily confined within the subsurface of the southern San Joaquin basin. Due to this mode of deposition and the …
Seismic Expressions Of Paleokarst, Olanrewaju Ayodapo Aboaba
Seismic Expressions Of Paleokarst, Olanrewaju Ayodapo Aboaba
Graduate Theses and Dissertations
Paleokarst are characterized by epigene and/or hypogene processes in their formation and hold significant numbers of hydrocarbons and other natural resources. This dissertation examines worldwide seismic expression of paleokarst; and specifically, the characterization of paleokarst reservoirs developed across the Cherokee Platform, and in the Arkoma Basin, Oklahoma.
Worldwide subsurface paleokarst formations are of Precambrian to Miocene age and found at depths less than 200 m to as great as 8000 m. Karst can be are expressed on seismic records as sinkholes, paleocave collapse, and tower morphologies. Seismic modeling indicates that karst can be modeled and imaged to better understand its …
Exploring Sediment Compaction In Experimental Deltas: Towards A Meso-Scale Understanding Of Coastal Subsidence Patterns, Samuel Mason Zapp
Exploring Sediment Compaction In Experimental Deltas: Towards A Meso-Scale Understanding Of Coastal Subsidence Patterns, Samuel Mason Zapp
Graduate Theses and Dissertations
Subsidence in low elevation coastal areas has been extensively researched through direct field measurement, numerical modelling, and stratigraphic reconstruction of ancient sediment deposits. Here I present the first investigation of subsidence due to sediment compaction and consolidation in two laboratory scale river delta experiments. Compactional subsidence rates have never been thoroughly quantified in the experimental setting, though this mechanism is found to be a primary creator of total relative sea level rise which will likely cause coastlines to retreat in the coming years. Spatial and temporal trends in subsidence rates in the experimental setting may elucidate behavior which cannot be …
The Fold Illusion: The Origins And Implications Of Ogives On Silicic Lavas, Graham Dm Andrews, Stuart Kenderes, Alan Whittington, Shelby L. Isom, Sarah Brown, Holly Danielle Pettus, Brenna Cole, Kailee Gokey
The Fold Illusion: The Origins And Implications Of Ogives On Silicic Lavas, Graham Dm Andrews, Stuart Kenderes, Alan Whittington, Shelby L. Isom, Sarah Brown, Holly Danielle Pettus, Brenna Cole, Kailee Gokey
Faculty & Staff Scholarship
Folds on the surfaces of mafic lavas are among the most readily recognized geological structures and are used as first-order criteria for identifying ancient lavas on Earth and other planetary bodies. However, the presence of surface-folds on the surface of silicic lavas is contested in this study and we challenge the widely accepted interpretation that silicic lava surfaces contain folds using examples from the western United States and Sardinia, Italy. We interpret the ridges and troughs on their upper surfaces, typically referred to as ‘ogives’ or ‘pressure ridges’, as fracture-bound structures rather than folds. We report on the absence of …
Boron Adsorption In Clay Minerals: Implications For Martian Groundwater Chemistry And Prebiotic Processes, Matthew A. Nellessen, Laura Crossey, Patrick J. Gasda, Horton Newsom, Abdulmehdi Ali, Eric J. Peterson, Nina Lanza, Adriana Reyes-Newell, Dorothea Delapp, Chris Yeager, Andrea Labouriau, Roger C. Wiens, Samuel Clegg, Shelbie Legett, Debarati Das
Boron Adsorption In Clay Minerals: Implications For Martian Groundwater Chemistry And Prebiotic Processes, Matthew A. Nellessen, Laura Crossey, Patrick J. Gasda, Horton Newsom, Abdulmehdi Ali, Eric J. Peterson, Nina Lanza, Adriana Reyes-Newell, Dorothea Delapp, Chris Yeager, Andrea Labouriau, Roger C. Wiens, Samuel Clegg, Shelbie Legett, Debarati Das
Earth and Planetary Sciences ETDs
Boron has been detected on Mars [Gasda et al., 2017, Das et al., 2019, 2020] within calciumsulfate veins found within clay-rich rocks on Mars by the Mars Science Laboratory (MSL) rover using Laser Induced Breakdown Spectroscopy (LIBS) analysis. Boron plays a vital role in stabilizing ribose on Earth and has been suggested as a key requirement for life [Scorei et al., 2006, 2012; Furukawa et al., 2013, 2017; Becker et al., 2019]. Additionally, boron readily adsorbs to phyllosilicate clay minerals and is often associated with biologic processes in clay soils. The discovery of boron on Mars in proximity to phyllosilicate …
The Future Environmental And Health Impacts Of Coal, Robert B. Finkelman, Amy L. Wolfe, Michael S. Hendryx
The Future Environmental And Health Impacts Of Coal, Robert B. Finkelman, Amy L. Wolfe, Michael S. Hendryx
Faculty, Staff, and Affiliated Publications--KGS
In the United States, coal consumption in the last 12 years has declined from 1,045,140 million short tons in 2007 to 539,420 million short tons in 2019, a decrease of almost 50%. During that period the number of electric power coal generators has declined from 1,470 to 738 accounting for 21% of capacity. An even more dramatic decrease in coal use has occurred in Western Europe. This significant reduction in coal use and the concomitant closure of coal mines and coal-burning power plants will result in substantially cleaner air, reductions in respiratory problems such as asthma, less heart disease, fewer …
Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella
Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella
USF Tampa Graduate Theses and Dissertations
Warm, intermediate-depth Southern Ocean waters are implicated in recent Antarctic ice mass loss. Direct observations of Antarctic Ice Sheet (AIS) retreat are temporally limited, necessitating paleoceanographic records of ocean-ice interactions during past warm climate intervals. Deepsea and ice-proximal sediments record orbitally-paced glacial-interglacial fluctuations in AIS volume during the Plio-Pleistocene (last 5 million years; Ma), but the total contribution of the AIS and the role of ocean heat in these fluctuations remain unresolved. To address the response of Antarctica’s ice sheets to changing ocean temperatures during the Plio-Pleistocene, International Ocean Discovery Program (IODP) Expedition 374 recovered sediments from the Ross Sea …
Detrital Zircon (U-Th)/He Thermochronology In The Greater Caucasus: Implications For Thermal And Tectonic History Along-Strike, Kate Gutterman
Detrital Zircon (U-Th)/He Thermochronology In The Greater Caucasus: Implications For Thermal And Tectonic History Along-Strike, Kate Gutterman
LSU Master's Theses
Located along the northernmost boundary of the Arabia-Eurasia collision zone, the Greater Caucasus are a young, actively deforming mountain range striking WNW-ESE between the Black and Caspian Seas. Previous thermochronometric studies predominantly focused on the western portion of the range partially constrain the thermal and tectonic history of the Greater Caucasus. However, due to the complex nature of the tectonics in the region, multiple competing tectonic models have been suggested to explain the exact timing of collision and onset of rapid uplift. Furthermore, the Greater Caucasus exhibit competing along-strike gradients in modern shortening rates, mean annual precipitation, structural architecture and …
U/Pb Zircon Ages Of Felsic Veins In The Sawtooth Metamorphic Complex, Idaho, U.S.A: Implications For Magmatism And Vein Source, Kyle Tollefson
U/Pb Zircon Ages Of Felsic Veins In The Sawtooth Metamorphic Complex, Idaho, U.S.A: Implications For Magmatism And Vein Source, Kyle Tollefson
LSU Master's Theses
Veins associated with igneous activity provide numerous insights into the geologic history of an area. The Sawtooth Metamorphic Complex (SMC) in Idaho is a roof pendent of highgrade rocks cross-cut by numerous felsic veins of unknown age and source. Obtaining U/Pb zircon geochronology of these veins can facilitate understanding the ages of magmatism in the region, their source, when nearby batholiths were juxtaposed to the SMC, and provide additional insights into the geologic evolution of the area. Each potential source of these veins has a distinct age: the Sawtooth batholith (ca. 47 Ma), the Idaho batholith (98-53 Ma), an anatectic …
Porosity And Permeability Extremes In An Eogenetic Carbonate Platform: Mechanisms For Formation And Implications For Fluid Flow, Charles I. Breithaupt
Porosity And Permeability Extremes In An Eogenetic Carbonate Platform: Mechanisms For Formation And Implications For Fluid Flow, Charles I. Breithaupt
USF Tampa Graduate Theses and Dissertations
Carbonate rocks contain about a third of the worlds drinking water and host 60-70% of proven hydrocarbon reserves. Effective development and management of these resources relies heavily on geologic concepts used to predict the distribution, and magnitude of porosity and permeability in the aquifer or reservoir. Most geologic concepts used for flow prediction have been developed in telegenic limestones, where fracture networks, bedding plains, and conduits hosted in effectively impermeable bedrock control the movement of fluids, and evolution of porosity. However, a growing body of work has recognized fluid flow within eogenetic limestones is fundamentally different, and that new concepts …
A Geologically Based Indoor-Radon Potential Map Of Kentucky, William C. Haneberg, Amanda T. Wiggins, Douglas C. Curl, Stephen F. Greb, William M. Andrews Jr., Kathy Rademacher, Mary Kay Rayens, Ellen J. Hahn
A Geologically Based Indoor-Radon Potential Map Of Kentucky, William C. Haneberg, Amanda T. Wiggins, Douglas C. Curl, Stephen F. Greb, William M. Andrews Jr., Kathy Rademacher, Mary Kay Rayens, Ellen J. Hahn
Faculty, Staff, and Affiliated Publications--KGS
We combined 71,930 short-term (median duration 4 days) home radon test results with 1:24,000-scale bedrock geologic map coverage of Kentucky to produce a statewide geologically based indoor-radon potential map. The test results were positively skewed with a mean of 266 Bq/m3, median of 122 Bq/m3, and 75th percentile of 289 Bq/m3. We identified 106 formations with ≥10 test results. Analysis of results from 20 predominantly monolithologic formations showed indoor-radon concentrations to be positively skewed on a formation-by-formation basis, with a proportional relationship between sample means and standard deviations. Limestone (median 170 Bq/m3) …
Using Indigenous Research Frameworks In The Multiple Contexts Of Research, Teaching, Mentoring, And Leading, Darryl Reano
Using Indigenous Research Frameworks In The Multiple Contexts Of Research, Teaching, Mentoring, And Leading, Darryl Reano
The Qualitative Report
Indigenous research frameworks can be used to effectively engage Indigenous communities and students in Western modern science through transparent and respectful communication. Currently, much of the academic research taking place within Indigenous communities marginalizes Indigenous Knowledge, does not promote long-term accountability to Indigenous communities and their relations, and withholds respect for the spiritual values that many Indigenous communities embrace. Indigenous research frameworks address these concerns within the academic research process by promoting values such as: relationality, multilogicality, and the centralization of Indigenous perspectives. Indigenous research frameworks provide a framework that can be used in multiple contexts within higher education to …
The Role Of Eolian-Fluvial Interactions And Dune Dams In Landscape Change, Late Pleistocene-Holocene, Mojave Desert, Usa, Mark R. Sweeney, Eric V. Mcdonald, Lucas P. Chabela, Paul R. Hanson
The Role Of Eolian-Fluvial Interactions And Dune Dams In Landscape Change, Late Pleistocene-Holocene, Mojave Desert, Usa, Mark R. Sweeney, Eric V. Mcdonald, Lucas P. Chabela, Paul R. Hanson
School of Natural Resources: Faculty Publications
The formation of the Kelso Dunes in the eastern Mojave Desert, California, was a landscape-changing event triggered by an increase in sediment supply that followed the incision of Afton Canyon by the Mojave River ca. 25 ka. Eastward migration of sand dunes occurred along a well-defined eolian transport corridor. Dunes temporarily blocked washes resulting in substantial aggradation of eolian and fluvial sediments. Stratigraphic exposures reveal numerous fining-up sequences with interbedded eolian sands that provide evidence of dune dams and subsequent aggradation. Luminescence ages reveal that dune blocking and aggradation correspond to a regional pulse of alluvial fan sedimentation that occurred …
Groundwater Withdrawal Prediction Using Integrated Multitemporal Remote Sensing Data Sets And Machine Learning, S. Majumdar, Ryan G. Smith, J. J. Butler, V. Lakshmi
Groundwater Withdrawal Prediction Using Integrated Multitemporal Remote Sensing Data Sets And Machine Learning, S. Majumdar, Ryan G. Smith, J. J. Butler, V. Lakshmi
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Effective monitoring of groundwater withdrawals is necessary to help mitigate the negative impacts of aquifer depletion. In this study, we develop a holistic approach that combines water balance components with a machine learning model to estimate groundwater withdrawals. We use both multitemporal satellite and modeled data from sensors that measure different components of the water balance and land use at varying spatial and temporal resolutions. These remote sensing products include evapotranspiration, precipitation, and land cover. Due to the inherent complexity of integrating these data sets and subsequently relating them to groundwater withdrawals using physical models, we apply random forests -- …
Drastic Vegetation Change In The Guajira Peninsula (Colombia) During The Neogene, Carlos Jaramillo, Pierre Sepulchre, Damian Cardenas, Francisca Oboh-Ikuenobe, For Full List Of Authors, See Publisher's Website.
Drastic Vegetation Change In The Guajira Peninsula (Colombia) During The Neogene, Carlos Jaramillo, Pierre Sepulchre, Damian Cardenas, Francisca Oboh-Ikuenobe, For Full List Of Authors, See Publisher's Website.
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Dry biomes occupy ~35% of the landscape in the Neotropics, but these are heavily human-disturbed. In spite of their importance, we still do not fully understand their origins and how they are sustained. The Guajira Peninsula in northern Colombia is dominated by dry biomes and has a rich Neogene fossil record. Here, we have analyzed its changes in vegetation and precipitation during the Neogene using a fossil pollen and spore dataset of 20 samples taken from a well and we also dated the stratigraphic sequence using microfossils. In addition, we analyzed the pollen and spore contents of 10 Holocene samples …
A Solution For Funding The Development Of Technology In Oilwell Drilling, Dalmo S. Amorim, Otto L. A. Santos, Ricardo C. Azevedo, Ana Carolina Chieregati
A Solution For Funding The Development Of Technology In Oilwell Drilling, Dalmo S. Amorim, Otto L. A. Santos, Ricardo C. Azevedo, Ana Carolina Chieregati
Faculty Publications
This article proposes a novel methodology to solve an existing gap in benchmark definition by the adoption of statistically defined benchmarks as references to test products or technical procedures. In a win-win partnership, remuneration is made upon realistic bases of comparison being proportional to existing risks. However, establishing values for benchmarks is rarely unanimous if asked to different persons involved in drilling analysis. Conventional benchmarking, which enhances few results and leaves aside poor operational performances, produces references that do not properly represent the geological environment. Nonetheless, when testing new products, it serves as reference to remunerate suppliers. The review of …
Twitter Reveals Human Mobility Dynamics During The Covid-19 Pandemic, Xiao Huang, Zhenlong Li, Yuqin Jiang, Xiaoming Li, Dwayne Porter
Twitter Reveals Human Mobility Dynamics During The Covid-19 Pandemic, Xiao Huang, Zhenlong Li, Yuqin Jiang, Xiaoming Li, Dwayne Porter
Geosciences Faculty Publications and Presentations
The current COVID-19 pandemic raises concerns worldwide, leading to serious health, economic, and social challenges. The rapid spread of the virus at a global scale highlights the need for a more harmonized, less privacy-concerning, easily accessible approach to monitoring the human mobility that has proven to be associated with viral transmission. In this study, we analyzed over 580 million tweets worldwide to see how global collaborative efforts in reducing human mobility are reflected from the user-generated information at the global, country, and U.S. state scale. Considering the multifaceted nature of mobility, we propose two types of distance: the single-day distance …
Synthesis And Ftir Characterization Of Mg-Hydroxylapatite Derived From Dolostone With High Dolomite Mineral Content, Wilson L. Mahene, Charles Gervas, Askwar H. Hilonga, Revocatus L. Machunda
Synthesis And Ftir Characterization Of Mg-Hydroxylapatite Derived From Dolostone With High Dolomite Mineral Content, Wilson L. Mahene, Charles Gervas, Askwar H. Hilonga, Revocatus L. Machunda
Tanzania Journal of Science
We present the synthesis of magnesium-substituted hydroxylapatite starting from locally available dolostone. The apatite was prepared by a reaction between heat pre-treated dolostone powder with phosphoric acid, maintained at the pH of 12.5 using sodium hydroxide. The resultant material was then calcined at 500 °C, 600 °C, 700 °C, 800 °C and 900 °C. The precursor dolostone was characterized by organic elemental analyser (CHNS-O analyser), X-ray fluorescence (XRF) and Fourier transform infrared spectroscopy (FTIR), while the synthesized material was characterized by using FTIR. Results indicated that the dominant mineral in the carbonate rock materials was near-stoichiometric dolomite, while the synthesized …
Coal Exploration Using Electrical Resistivity Method In Some Parts Of Benue Trough, Nigeria, Saminu Olatunji, Abdulgafar T. Jimoh
Coal Exploration Using Electrical Resistivity Method In Some Parts Of Benue Trough, Nigeria, Saminu Olatunji, Abdulgafar T. Jimoh
Tanzania Journal of Science
Geoelectrical resistivity sounding technique was used to delineate the occurrence and extents of coal seam. Fifteen points were sounded with Schlumberger configuration in the suspected coal deposit site bounded by longitudes 7.344° E and 7.366° E, and latitudes 7.318° N and 7.33° N. The vertical electrical sounding (VES) data were analyzed and the corresponding geo-electric parameters at various depths were modeled. The earth model within the study area was correlated with available lithology of a nearby mine site. The sounding signatures are KQHK and KHK curve types which revealed five to six distinct geo-electrical equivalent layers. The wet to dry …
Geological And Geochemical Characterisation Of Pegmatites Around Olode, Southwestern Nigeria, Razak O. Jimoh, Akinade S. Olatunji
Geological And Geochemical Characterisation Of Pegmatites Around Olode, Southwestern Nigeria, Razak O. Jimoh, Akinade S. Olatunji
Tanzania Journal of Science
Olode is prolific in terms of pegmatites, occurring in different ways as large intrusive bodies, as veins and dykes, discordantly intruding the host rocks of mica schist, gneiss and granite. This study is aimed at the geological and geochemical characterisation of pegmatites around Olode. Field investigation was undertaken to determine the occurrences and relationships of the pegmatites with the host rocks. Fresh pegmatite samples were studied petrographically and geochemically. Two main lithologically and chronologically different groups of pegmatites were distinguishable in the study area. These were the tourmaline pegmatites associated with the Older Granite rocks and the NE-SW trending beryl-bearing …
Sensitivity Analysis And Uncertainty Parameter Quantification In A Regression Model: The Case Of Deforestation In Tanzania, Thadei Sagamiko, Nyimvua Shaban, Isambi S. Mbalawata
Sensitivity Analysis And Uncertainty Parameter Quantification In A Regression Model: The Case Of Deforestation In Tanzania, Thadei Sagamiko, Nyimvua Shaban, Isambi S. Mbalawata
Tanzania Journal of Science
In this paper a multiple regression model for the economic factors and policy that influence the rate of deforestation in Tanzania is formulated. Sensitivity analysis for parameters of explanatory variables using one-at-a time and direct methods is carried out and the model is fitted by classical least square (LSQ) and Markov Chain Monte Carlo (MCMC) methods. Uncertainty quantification of parameters by adaptive Markov Chain Monte Carlo methods is performed. The coefficient of determination indicates that 87% of deforestation rate is explained by explanatory variables captured in the model. Household poverty rate is found to be the most sensitive factor to …
Assessment And Integration Of Socioeconomic And Demographic Factors In The Implementation Of Integrated Water Resources Management In The Lake Chad Basin, Nodjidoumde Mbaigoto
Assessment And Integration Of Socioeconomic And Demographic Factors In The Implementation Of Integrated Water Resources Management In The Lake Chad Basin, Nodjidoumde Mbaigoto
USF Tampa Graduate Theses and Dissertations
Most developing countries have responded to the 2002 World Summit on Sustainable Development (WSSD) call to implement Integrated Water Resources Management (IWRM) in their national water policy to reach water sustainability and socioeconomic welfare. Despite the Lake Chad Basin Commission's adoption of the IWRM principles, the basin experiences a massive humanitarian crisis driven by the lake's shrinkage, the water shortage for food production, the rapid population growth, and the terrorist attacks perpetrated by Boko Haram. This study sought to assess the socioeconomic and demographic status of people living upstream of Lake Chad in order to understand the challenges associated with …