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Articles 301 - 330 of 441
Full-Text Articles in Geology
Effects Of Carbon Dioxide And Clouds On Temperature, Hyunsoo Lee, Hee Woon Cheong
Effects Of Carbon Dioxide And Clouds On Temperature, Hyunsoo Lee, Hee Woon Cheong
Geosciences Faculty Publications
With the observed rise in temperature, many researchers have tried to identify the causes of such climate change to help mitigate its effects. The objective of this study is to determine whether, under the same carbon dioxide (CO 2 ) concentrations, CO 2 with lower cloud coverage would raise the temperature at a greater rate than CO 2 with higher cloud coverage. The hypothesis was tested through big data analysis and modeling. The relationships between the temperature and the CO 2 emissions, the temperature and the cloud coverage, and the CO 2 emissions and the cloud coverage were identified using …
Mapping The Yearly Extent Of Surface Coal Mining In Central Appalachia Using Landsat And Google Earth Engine, Andrew A. Pericak, Christian J. Thomas, David A. Kroodsma, Matthew F. Wasson, Matthew R.V. Ross, Nicolas E. Clinton, David J. Campagna, Yolandita Franklin, Emily S. Bernhardt, John F. Amos
Mapping The Yearly Extent Of Surface Coal Mining In Central Appalachia Using Landsat And Google Earth Engine, Andrew A. Pericak, Christian J. Thomas, David A. Kroodsma, Matthew F. Wasson, Matthew R.V. Ross, Nicolas E. Clinton, David J. Campagna, Yolandita Franklin, Emily S. Bernhardt, John F. Amos
Faculty & Staff Scholarship
Surface mining for coal has taken place in the Central Appalachian region of the United States for well over a century, with a notable increase since the 1970s. Researchers have quantified the ecosystem and health impacts stemming from mining, relying in part on a geospatial dataset defining surface mining’s extent at a decadal interval. This dataset, how- ever, does not deliver the temporal resolution necessary to support research that could establish causal links between mining activity and environmental or public health and safety outcomes, nor has it been updated since 2005. Here we use Google Earth Engine and Landsat imagery …
Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr.
Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr.
Robert F. Diffendal, Jr., Publications
In his new best-selling book, Peter Brannen, award-winning science writer, takes you on a fascinating trip through the run-up to the end of the Cretaceous extinction event and the K-Pg (Cretaceous/Paleogene) boundary, formerly called the K-T (Cretaceous/Tertiary) boundary.
Brannen interviewed many scientists who studied these events and went on field trips with them to major Cretaceous sites and to those where earlier and later extinction events happened. He presents clear explanations of what is known and not known about all of these events in a largely error-free book. Brannen details the other four big extinction events in geologic history: the …
Global Climate Change I-Ii, Kendall Barrett Sooter, Dione Rossiter, Costanza Rampini
Global Climate Change I-Ii, Kendall Barrett Sooter, Dione Rossiter, Costanza Rampini
Faculty Publications, Environmental Studies
Many different scientific observations and measurements indicate that Earth is experiencing global-scale changes in climate, i.e., in the long-term distributions of temperature, cloud cover, precipitation, and extreme weather events. Scientific consensus considers most these changes to be caused or accelerated by human activities. The economic, ecological, social, and cultural challenges caused by global climate change will affect everyone on the planet, and are very likely to have disproportionate impacts on developing nations. In this course, we will study global climate change from an interdisciplinary perspective, incorporating natural and social science approaches to understanding processes and effects. We will study the …
Lead In The Environment, Msn Module, Dawn Blue
Lead In The Environment, Msn Module, Dawn Blue
Q2S Enhancing Pedagogy
Module for MSN program in toxicology on lead in the environment.
Ua37/42 Faculty Personal Papers Nina Hammer, Wku Archives
Ua37/42 Faculty Personal Papers Nina Hammer, Wku Archives
WKU Archives Collection Inventories
Personal papers of Nina Hammer, Bowling Green Business University Registrar 1938-1963; WKU Registrar 1963-1969.
Failure Of The Alexander Dam Embankment And Reconstruction Using Drainage Mitigation On Kauai, Hawaii, 1930-1932, Kerry D. Cato, J. David Rogers
Failure Of The Alexander Dam Embankment And Reconstruction Using Drainage Mitigation On Kauai, Hawaii, 1930-1932, Kerry D. Cato, J. David Rogers
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Alexander Dam is a hydraulic fill earth dam and the second-highest embankment dam in Hawaii, having been built in 1929-1932 on the south side of the Hawaiian island of Kauai to provide irrigation for McBryde Sugar Company Ltd. It was constructed across Wahiawa Stream mauka (Hawaiian for "stream that comes from the mountains," literally "toward the mountains"), upstream of Kalaheo, to store 800 million gallons (5 million m3) of water to irrigate sugarcane fields. The embankment dam was intended to have a maximum height of 125 ft (38 m), a crest length of 620 ft (189 m), and a maximum …
Fight And Air Exposure Times Of Caught And Released Salmonids From The South Fork Snake River, Curtis J. Roth, Daniel J. Schill, Michael C. Quist
Fight And Air Exposure Times Of Caught And Released Salmonids From The South Fork Snake River, Curtis J. Roth, Daniel J. Schill, Michael C. Quist
United States Geological Survey: Staff Publications
Catch-and-release regulations are among the most common types of fishing regulations. In recent years, concerns have arisen regarding the exposure of fish to air during catch-and-release angling. The purpose of our study was to quantify the length of time angled fish were exposed to air by anglers in a typical catch-and-release fishery and relate it to the lengths of time reported to produce negative effects. In total, 312 individual anglers were observed on the South Fork Snake River, Idaho, from May through August 2016. Fight time varied from 1.1 s to 230.0 s, and average fight time was 40.0 s …
Testing And Evaluation Of Shale Stability For Zubair Shale Formation, Ahmed K. Abbas, Ralph E. Flori, Ahmed Al-Anssari, Mortadha Alsaba
Testing And Evaluation Of Shale Stability For Zubair Shale Formation, Ahmed K. Abbas, Ralph E. Flori, Ahmed Al-Anssari, Mortadha Alsaba
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Zubair Formation consists of approximately 55% shale, which causes almost 70% of wellbore problems due to incompatibilities of drilling fluids and shale formations. The most common and effective solution to shale instability is through the design and selection of drilling fluids. Understanding the interaction between drilling fluids and shale has been a challenge due to the complexity of both physical and chemical variations in shale formations. This paper presents some of the important laboratory and well-site testing techniques that are often used by mud engineers for characterizing and remediating drilling fluids and shale interaction. Well-preserved shale samples were analyzed to …
An Overview Of Anorthosite-Bearing Layered Intrusions In The Archaean Craton Of Southern West Greenland And The Superior Province Of Canada: Implications For Archaean Tectonics And The Origin Of Megacrystic Plagioclase, Ali Polat, Fred J. Longstaffe, Robert Frei
An Overview Of Anorthosite-Bearing Layered Intrusions In The Archaean Craton Of Southern West Greenland And The Superior Province Of Canada: Implications For Archaean Tectonics And The Origin Of Megacrystic Plagioclase, Ali Polat, Fred J. Longstaffe, Robert Frei
Earth Sciences Publications
Anorthosite-bearing layered intrusions are unique to the Archaean rock record and are abundant in the Archaean craton of southern West Greenland and the Superior Province of Canada. These layered intrusions consist mainly of ultramafic rocks, gabbros, leucogabbros and anorthosites, and typically contain high-Ca (>An70) megacrystic (2–30 cm in diameter) plagioclase in anorthosite and leucogabbro units. They are spatially and temporally associated with basalt-dominated greenstone belts and are intruded by syn-to post-tectonic granitoid rocks. The layered intrusions, greenstone belts and granitoids all share the geochemical characteristics of Phanerozoic subduction zone magmas, suggesting that they formed mainly in a …
Petrogenetic And Geodynamic Origin Of The Neoarchean Doré Lake Complex, Abitibi Subprovince, Superior Province, Canada, Ali Polat, Robert Frei, Fred J. Longstaffe, Ryan Woods
Petrogenetic And Geodynamic Origin Of The Neoarchean Doré Lake Complex, Abitibi Subprovince, Superior Province, Canada, Ali Polat, Robert Frei, Fred J. Longstaffe, Ryan Woods
Earth Sciences Publications
The Neoarchean (ca. 2728 Ma) anorthosite-bearing Doré Lake Complex in the northeastern Abitibi subprovince, Quebec, was emplaced into an association of intra-oceanic tholeiitic basalts and gabbros known as the Obatogamau Formation. The Obatogamau Formation constitutes the lower part of the Roy Group, which is composed of two cycles of tholeiitic-to-calc-alkaline volcanic and volcaniclastic rocks, siliciclastic and chemical sedimentary rocks, and layered mafic-to-ultramafic sills. In this study, we report major and trace element results, and Nd, Sr, Pb and O isotope data for anorthosites, leucogabbros, gabbros and mafic dykes from the Doré Lake Complex and spatially associated basalts and gabbros of …
Petrology And Geochemistry Of The Tasse Mantle Xenoliths Of The Canadian Cordillera: A Record Of Archean To Quaternary Mantle Growth, Metasomatism, Removal, And Melting, Ali Polat, Robert Frei, Fred J. Longstaffe, Derek J. Thorkelson, Eyal Friedman
Petrology And Geochemistry Of The Tasse Mantle Xenoliths Of The Canadian Cordillera: A Record Of Archean To Quaternary Mantle Growth, Metasomatism, Removal, And Melting, Ali Polat, Robert Frei, Fred J. Longstaffe, Derek J. Thorkelson, Eyal Friedman
Earth Sciences Publications
Mantle xenoliths hosted by the Quaternary Tasse alkaline basalts in the Canadian Cordillera, southeastern British Columbia, are mostly spinel lherzolite originating from subcontinental lithospheric mantle. The xenoliths contain abundant feldspar veins, melt pockets and spongy clinopyroxene, recording extensive alkaline metasomatism and partial melting. Feldspar occurs as veins and interstitial crystal in melt pockets. Melt pockets occur mainly at triple junctions, along grain boundaries, and consist mainly of olivine, cpx, opx and spinel surrounded by interstitial feldspar. The Nd, Sr and Pb isotopic compositions of the xenoliths indicate that their sources are characterized by variable mixtures of depleted MORB mantle and …
The Flathead Catfish Invasion Of The Great Lakes, Pam L. Fuller, Gary E. Whelan
The Flathead Catfish Invasion Of The Great Lakes, Pam L. Fuller, Gary E. Whelan
United States Geological Survey: Staff Publications
A detailed review of historical literature andmuseumdata revealed that flathead catfish were not historically native in the Great Lakes Basin, with the possible exception of a relict population in Lake Erie. The species has invaded Lake Erie, Lake St. Clair, Lake Huron, nearly all drainages in Michigan, and the Fox/Wolf and Milwaukee drainages in Wisconsin. They have not been collected from Lake Superior yet, and the temperature suitability of that lake is questionable. Flathead catfish have been stocked sparingly in the Great Lakes and is not the mechanism responsible for their spread. A stocking in 1968 in Ohio may be …
Past Role And Future Outlook Of The Conservation Reserve Program For Supporting Honey Bees In The Great Plains, Clint R.V. Otto, Haochi Zheng, Alisa L. Gallant, Rich Iovanna, Benjamin L. Carlson, Matthew D. Smart, Skip Hyberg
Past Role And Future Outlook Of The Conservation Reserve Program For Supporting Honey Bees In The Great Plains, Clint R.V. Otto, Haochi Zheng, Alisa L. Gallant, Rich Iovanna, Benjamin L. Carlson, Matthew D. Smart, Skip Hyberg
United States Geological Survey: Staff Publications
Human dependence on insect pollinators continues to grow even as pollinators face global declines. The Northern Great Plains (NGP), a region often referred to as America’s last honey bee (Apis mellifera) refuge, has undergone rapid land-cover change due to cropland expansion and weakened land conservation programs. We conducted a trend analysis and estimated conversion rates of Conservation Reserve Program (CRP) enrollments around bee apiaries from 2006 to 2016 and developed models to identify areas of habitat loss. Our analysis revealed that NGP apiaries lost over 53% of lands enrolled in the CRP, and the rate of loss was highest in …
The Pothole Hydrology-Linked Systems Simulator (Phyliss)—Development And Application Of A Systems Model For Prairie-Pothole Wetlands, Owen P. Mckenna, David M. Mushet, Eric J. Scherff, Kyle I. Mclean, Christopher T. Mills
The Pothole Hydrology-Linked Systems Simulator (Phyliss)—Development And Application Of A Systems Model For Prairie-Pothole Wetlands, Owen P. Mckenna, David M. Mushet, Eric J. Scherff, Kyle I. Mclean, Christopher T. Mills
United States Geological Survey: Publications
The North American Prairie Pothole Region covers about 770,000 square kilometers of the United States and Canada (including parts of 5 States and 3 provinces: North Dakota, South Dakota, Montana, Minnesota, Iowa, Saskatchewan, Manitoba, and Alberta). The Laurentide Ice Sheet shaped the landscape of the region about 12,000 to 14,000 years ago. The retreat of the ice sheet left behind low-permeability glacial till and a landscape dotted with millions of depressions known today as prairie potholes. The wetlands that subsequently formed in these depressions, prairie-pothole wetlands, provide critical migratory-bird habitat and support dynamic aquatic communities. Extensive grasslands and productive agricultural …
Appendix 1. Testing The Influence Of Management Regime And Year On Vegetation Structure Variables On Two Grass Types On Federal Lands Managed Under An Adaptive-Management Framework By The U.S. Fish And Wildlife Service In North Dakota, South Dakota, Minnesota, And Montana, 2011–13, J.J Gannon, T.L. Shaffer, C.T. Moore
Appendix 1. Testing The Influence Of Management Regime And Year On Vegetation Structure Variables On Two Grass Types On Federal Lands Managed Under An Adaptive-Management Framework By The U.S. Fish And Wildlife Service In North Dakota, South Dakota, Minnesota, And Montana, 2011–13, J.J Gannon, T.L. Shaffer, C.T. Moore
United States Geological Survey: Publications
Generalized linear mixed model (assuming a beta distribution with a logit link) testing the influence of management regime and year on mean bare-ground cover (percent) on two grass types on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service (Gannon and others, 2013) in North Dakota, South Dakota, Minnesota, and Montana, 2011–13.
John Frank Stevens: Panama Canal Mastermind And Pioneering Railroad Pathfinder, J. David Rogers, Lawrence M. Magura
John Frank Stevens: Panama Canal Mastermind And Pioneering Railroad Pathfinder, J. David Rogers, Lawrence M. Magura
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
John Frank Stevens began his civil engineering career as a rodman on a survey crew in Maine in 1872. He soon moved to Minneapolis, where he apprenticed himself, eventually becoming Assistant City Engineer. In 1876 he began working for railroads in the western United States. In 1882 Stevens began working for a contractor laying tracks for the Canadian Pacific Railroad in Saskatchewan. The next spring he became assistant engineer of location for the Canadian Pacific, completing the first transcontinental line linking Montreal with Vancouver in 1888. In 1889 James Jerome Hill retained Stevens as chief pathfinder for the new Great …
A Simplified, Object-Based Framework For Efficient Landslide Inventorying Using Lidar Digital Elevation Model Derivatives, Michael D. Bunn, Ben A. Leshcinsky, Michael J. Olsen, Adam M. Booth
A Simplified, Object-Based Framework For Efficient Landslide Inventorying Using Lidar Digital Elevation Model Derivatives, Michael D. Bunn, Ben A. Leshcinsky, Michael J. Olsen, Adam M. Booth
Geology Faculty Publications and Presentations
Landslide inventory maps are critical to understand the factors governing landslide occurrence and estimate hazards or sediment delivery to channels. Numerous semi-automated approaches for landslide inventory mapping have been proposed to improve the efficiency and objectivity of the process, but these methods have not been widely adopted by practitioners because of the use of input parameters without physical meaning, a lack of transparency in machine-learning based mapping techniques, and limitations in resulting products, which are not ordinarily designed or tested on a large-scale or in diverse geologic units. To this end, this work presents a new semi-automated method, called the …
Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii
Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii
Contract Reports--KGS
The Rising Sun 7.5-minute quadrangle is located in northern Kentucky in the Outer Bluegrass physiographic province (McFarlan, 1943). The area is underlain by Upper Ordovician limestone and shale, and is characterized by low- to medium-relief topography. The oldest rock unit in the quadrangle is the Point Pleasant Formation, which consists of interbedded limestone and shale, and is exposed at the base of the bedrock uplands area south of Lower East Bend Bottom. The shale-dominated Kope Formation overlying the Point Pleasant Formation is exposed in most stream channels and underlies the valleys and hillslopes in the quadrangle. The Kope Formation is …
Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials, Joel C. Sercel, Mark A. Crawford, Christopher Dreyer, Egboche Unobe, Robert Jedicke, Stanley Love, Leslie S. Gertsch
Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials, Joel C. Sercel, Mark A. Crawford, Christopher Dreyer, Egboche Unobe, Robert Jedicke, Stanley Love, Leslie S. Gertsch
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
This paper presents the results of a program of computational modeling focused on elucidating the physics and chemical processes associated with the extraction of volatile materials from asteroid feedstocks with an eye toward use of the extracted materials for propulsion, radiation shielding, and replenishment of mission consumables. We present a math model of conductive heat transport, chemical processes, and gas escape by Darcian diffusion. Chemical processes in the model include pyrolysis of organic chemical constituents and thermal dehydration and decarbonization of hydrates and carbonates. The model is implemented in a spherical finite difference computational engine that predicts time histories of …
Disaster Risk In The Lake Nyos Area, Cameroon: Effects Of The Gas Hazard And Socially Produced Vulnerability, Mary Witucki
Disaster Risk In The Lake Nyos Area, Cameroon: Effects Of The Gas Hazard And Socially Produced Vulnerability, Mary Witucki
Dissertations, Master's Theses and Master's Reports
Effective disaster risk reduction (DRR) efforts depend on comprehensive risk assessments that consider potential hazard events and social vulnerability. The Lake Nyos Disaster (LND) caused the deaths of about 1,700 people, forced another 4,000 people from their homes, and left survivors more vulnerable to future hazards. There is considerable research on the gas hazard and some work on local vulnerability; however studies rarely consider both aspects of disaster risk (DR). This study addresses both the hazard and vulnerability and uses several qualitative and quantitative methods which have never been applied to LND survivor vulnerability or gas hazard. Interviews, participant observation, …
Conservation Limnogeology And Benthic Habitat Mapping In Central Lake Tanganyika (Tanzania), Joseph S. Lucas
Conservation Limnogeology And Benthic Habitat Mapping In Central Lake Tanganyika (Tanzania), Joseph S. Lucas
Theses and Dissertations--Earth and Environmental Sciences
Small scale protected zones are valuable for helping the health and productivity of fisheries at Lake Tanganyika (East Africa). Spatial placement of protected areas relies on accurate maps of benthic habitats, consisting of detailed bathymetry data and information on lake-floor substrates. This information is unknown for most of Lake Tanganyika. Fish diversity is known to correlate with rocky substrates in ≤ 30 m water depth, which provide spawning grounds for littoral and pelagic species. These benthic habitats form important targets for protected areas, if they can be precisely located.
At the NMVA, echosounding defined the position of the 30-m isobath …
Global Plate Motions And Earthquake Cycle Effects, Shannon E. Graham, John P. Loveless, Brendan J. Meade
Global Plate Motions And Earthquake Cycle Effects, Shannon E. Graham, John P. Loveless, Brendan J. Meade
Geosciences: Faculty Publications
The rotations of tectonic plates provide a partial description of the total observed displacements at the Earth’s surface. The estimated number of kinematically distinct plates has increased from 12 in 1990 to 56 in 2010 as a result of the increase in the number of kinematic observables. At length scales <1,000 km, rotation-only plate models are inaccurate because geodetic signals of long-term plate motions are complicated by earthquake cycle effects. Here we present results from a global block model that unifies large-scale plate motions and local earthquake cycle effects at plate boundaries. Incorporating the rotations of 307 distinct plates, elastic strain accumulation from 16 subduction zones and 1.59×107 km2 of fault system area, this model explains 19,664 interseismic GPS velocities at a resolution of 2.2 mm/year. Geodetically constrained fault slip deficit rates yield a cumulative global moment accumulation rate of 1.09 × 1022 N⋅m/year, 12% larger than the average annual coseismic moment release rate from 1900 to 2013. The potential contribution to the total moment rate budget can be estimated from the frequency distribution of the modeled fault slip-deficit rates, which follow an exponential distribution. Integrating this frequency distribution over all possible slip rates indicates that the geologic structures included in this reference global block model account for 98% of the global moment budget. Comparing our results with population distribution, we find that ∼50% of the world’s population lives within 200 km of an active fault with a slip rate >2 mm/year.
Paleogene-Early Neogene Palynomorphs From The Eastern Equatorial Atlantic And Southeastern Florida, Usa: Biostratigraphy And Paleoenvironmental Implications, Walaa K. Awad
Doctoral Dissertations
"The transition from greenhouse conditions (Paleocene-Eocene Thermal Maximum, PETM) to icehouse conditions (Early Oligocene) is not well documented in tropical-subtropical regions. One hundred and five samples from Ocean Drilling Program (ODP) Site 959 (Hole 959A and Hole 959D) in the Cote d'Ivoire-Ghana Transform Margin, Alo-1 Well in the northern Niger Delta (Anambra) Basin, Nigeria, and W-17001 in southeastern Florida were studied for their palynological contents. Dinoflagellate cysts were mainly utilized for age refinement and to detect subtle changes in paleoenvironment and paleoclimate during the Paleocene-Early Eocene (ODP Hole 959D and Alo-1 Well) and Late Eocene-Early Miocene (ODP Hole 959A and …
Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert
Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert
Geology Faculty Publications and Presentations
Winter precipitation in two headwaters catchments (elevation ~1600 m) in the rain shadow of the Cascades volcanic arc in south-central Oregon normally falls as snow. However, in water year 2015, winter precipitation fell mainly as rain. An eight year study of the unconfined pumice aquifer allowed inter-annual comparison of groundwater recharge during the freshet and discharge during the growing season. During these water years precipitation ranged from 67% (WY2014) to 132% (WY2017) of the 30 year average, and included the rain dominated winter of WY2015 when precipitation during the water year was 98% of the 30 year average. Change in …
Optimum Magnetometer Transect Spacing To Locate Legacy Oil And Gas Wells: Preliminary Results, Jason A. Patton, Michael G. Davis, Kenyon J. Gowing, Hunter B. Vickers
Optimum Magnetometer Transect Spacing To Locate Legacy Oil And Gas Wells: Preliminary Results, Jason A. Patton, Michael G. Davis, Kenyon J. Gowing, Hunter B. Vickers
Journal of the Arkansas Academy of Science
The purpose of this project was to examine the optimum transect spacing to locate legacy oil and gas wells using an Overhauser magnetometer. Widely known to be a potential environmental hazard, legacy oil and gas wells may act as a conduit for methane and/or deeper subsurface fluids (naturally occurring brines, injected waste fluids, or injected CO2) to the surface or shallow subsurface. Many plugged wells have all surface equipment removed leaving no visible trace at the surface and thus making the environmental assessment of these wells difficult. Using a magnetometer along a set of predefined transects, magnetic anomalies …
Valley Bottom Position And The Occurrence Of Paleosols Affect Soc Dynamics, Benedict W. Ferguson
Valley Bottom Position And The Occurrence Of Paleosols Affect Soc Dynamics, Benedict W. Ferguson
Murray State Theses and Dissertations
Soil organic carbon (SOC) storage in depositional zones has been a growing topic of interest in recent years as these areas may be sinks of SOC. However, SOC dynamics greater than 1 m in depth in river valley bottom soils are not well understood. This study examines the soil organic carbon along three alluvial landscape positions in the forested, humid-subtropical setting of the Clarks River in the western Kentucky portion of the Mississippi River basin. These soil and depositional profiles range in age from ~8,000 years ago to modern, 21 cal yr. BP, (BP = AD 2010). The mean surface …
An Integrated Method For Forecasting Well Deliverability In Gas Condensate Reservoirs With Bottom Aquifer Drive, Abdulaziz Ellafi, Ralph E. Flori, Shari Dunn-Norman
An Integrated Method For Forecasting Well Deliverability In Gas Condensate Reservoirs With Bottom Aquifer Drive, Abdulaziz Ellafi, Ralph E. Flori, Shari Dunn-Norman
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Gas condensate reservoirs constitute a significant portion of global hydrocarbon reserves. In these reservoirs, liquids develop in the pore space once bottomhole pressure falls below dew point. This results in the formation of a liquid bank near the wellbore region which decreases gas mobility, which then reduces gas inflow. In such complex reservoirs, it is important to correctly describe PVT impacts, adjustments to well test analysis and inflow performance, and then combine all effects in the reservoir analysis. The literature contains many references to individual adjustments of PVT analysis, well testing, or inflow performance for gas condensate reservoirs, but few …
Miscible Gases Based Eor In Unconventional Liquids Rich Reservoirs: What We Can Learn, Dheiaa Alfarge, Mortadha Alsaba, Mingzhen Wei, Baojun Bai
Miscible Gases Based Eor In Unconventional Liquids Rich Reservoirs: What We Can Learn, Dheiaa Alfarge, Mortadha Alsaba, Mingzhen Wei, Baojun Bai
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Over the last decade, Unconventional Liquids Rich Reservoirs (ULR) have become the main target for oil and gas investors as conventional formations started to deplete and diminish in numbers. These unconventional plays have a huge oil reserve; however, the primary oil recovery factor is predicted to be less than 10%. Unconventional Improved Oil Recovery (UIOR) techniques are still a new concept in the oil industry since there is no commercial project reported for any IOR technique yet. Miscible gas based EOR technique might be the most potential strategy to improve oil recovery in such complex plays. In this study, a …
New Insights Of Low Salinity Water Flooding In Low Permeability-Low Porosity Clay Rich Sandstone Reservoir, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz
New Insights Of Low Salinity Water Flooding In Low Permeability-Low Porosity Clay Rich Sandstone Reservoir, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
One of the EOR technologies is low-salinity water flooding (LSWF) is an EOR method that operates at a lower cost than other EOR methods, which makes it a preferred area of interest for oil industry economists, who continue to call for EOR costs to come down. The aim is to minimize the possible cost to recover as much oil as possible. The performance of low salinity waterflooding in decreasing residual oil saturation in low permeability-porosity clay-rich sandstone reservoir. Porosity test, core flooding test, XRD and scanning electron microscopy (SEM) tests were achieved in this study. Salinity effect on the porosity, …