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Articles 22981 - 23010 of 29958
Full-Text Articles in Geology
Rocks To Roads To Ruin: A Brief History Of Western Kentucky’S Rock-Asphalt Industry, 1888–1957, J. Richard Bowersox
Rocks To Roads To Ruin: A Brief History Of Western Kentucky’S Rock-Asphalt Industry, 1888–1957, J. Richard Bowersox
Information Circular--KGS
The history of western Kentucky’s rock-asphalt industry required substantial research of primary sources to correct the disjointed and often conflicting record published to date. Its history is checkered with characters from visionary entrepreneurs and ambitious businessmen to financial scoundrels. The earliest evidence of exploitation of bitumen resources at the surface in western Kentucky is in Native American artifacts recovered from several sites. Early settlers in the region used heavy oil and bitumen found in seeps as lubricants and wood preservatives, among other uses. The commercial value of the widespread western Kentucky rock-asphalt deposits was first recognized in the 1880’s, leading …
Mapped Karst Groundwater Basins In The Elizabethtown 30 X 60 Minute Quadrangle, James C. Currens, Robert J. Blair
Mapped Karst Groundwater Basins In The Elizabethtown 30 X 60 Minute Quadrangle, James C. Currens, Robert J. Blair
Map and Chart--KGS
This map shows karst groundwater basins in the Elizabethtown 30 x 60 minute quadrangle, determined primarily by groundwater tracer studies. It can be used to quickly identify the groundwater basins and springs to which a site may drain. Major springs and the relative size of their catchment areas can be evaluated for potential as water supplies. The map also serves as a geographic index to literature on karst groundwater in the area.
Heavy-Oil And Bitumen Resources Of The Western Kentucky Tar Sands, J. Richard Bowersox
Heavy-Oil And Bitumen Resources Of The Western Kentucky Tar Sands, J. Richard Bowersox
Report of Investigations--KGS
Heavy-oil and bitumen resources in western Kentucky are present in the Upper Mississippian Big Clifty and Hardinsburg Sandstones and Lower Pennsylvanian Kyrock and Bee Spring Sandstone Members of the Caseyville Formation in a belt extending from Logan County on the south to Breckinridge and Hardin Counties on the north.
Net oil-saturated intervals in the tar sands range from 2.5 to 4.7 m thick, largely in downthrown fault blocks in and bounding the Rough Creek Graben. Records from 1,500 wells, analysis of reservoir properties from 3,769 plugs from 135 coreholes, and bulk volume of hydrocarbon calculated in 139 surface samples were …
Petrography, Mineralogy, And Geochemistry Of Greenish- And Reddish-Gray Siltstones Straddling The Vertebrate-Defined Permian–Triassic Boundary In South Africa, Jiawen Li
Honors Theses
The Permian–Triassic Mass Extinction (PTME) is considered the largest in Earth’s history, yet the terrestrial response is not well understood. The Karoo Basin, South Africa, hosts abundant exposures of terrestrial deposits that span the Permian– Triassic Boundary (PTB). The terrestrial PTB is defined by a turnover in vertebrate assemblage zones and has been associated with a transition from greenish-gray to reddish-gray siltstone. The current PTME model states that the siltstone color change is a reflection of aridification and eolian deposition, which is believed to represent rapid climate change directly linked with the event. Greenish- and reddish-gray siltstones were collected from …
Deserts And Wind, John J. Renton, Thomas Repine
Deserts And Wind, John J. Renton, Thomas Repine
Readings and Notes
About one third of Earth's land surface is either arid (< 10" ppt./yr or semi-arid (10" to 20" pt./yr). While most precipitation is in the form of rain, some may be provided by melting snow, mist, or fog. With limited availability of water, rocks are not subjected to chemical weathering but rather to physical weathering.
Igneous Rocks, John J. Renton, Thomas Repine
Modeling Bedrock Transmissivity; Implications For Contaminant Transport In An Overlying Glacial Aquifer System, Amanda Pruehs
Modeling Bedrock Transmissivity; Implications For Contaminant Transport In An Overlying Glacial Aquifer System, Amanda Pruehs
Wayne State University Theses
This study evaluated alternative representations of bedrock surface and bedrock transmissivity on advective transport predictions in an 11 km x 15 km x 116 m groundwater model. Bedrock topography, initially based on a map by Kunkle (1961), was reinterpreted using data from 227 additional bedrock penetrations drilled in the last 55 years. Varying assumptions of hydraulic conductivity were employed to model a range of bedrock conductivity from 1 to 3 orders of magnitude less than the overlying glacial aquifer system. MODPATH forward particle tracking and MT3DMS advective-dispersive transport modeling were employed to explore the influence of bedrock configuration and conductivity …
Use And Evaluation Of Lidar For Mapping Sinkholes In Royal Spring Groundwater Basin, Fidele Nsonguh Tibouo
Use And Evaluation Of Lidar For Mapping Sinkholes In Royal Spring Groundwater Basin, Fidele Nsonguh Tibouo
Theses and Dissertations--Earth and Environmental Sciences
This study utilizes a digital elevation model of the surface derived from high-resolution LiDAR (Light Detection and Ranging) and aerial-image technologies to map sinkholes in the Royal Spring groundwater basin. Shade-relief maps, with vertical exaggeration, were very helpful in the initial characterization of depressions. Then, aerial-photography sets were likewise helpful in identifying man-made structures such as retention basins, swimming pools, and parking lots, and to identify new sinkholes.
Field checking was necessary to further define depressions into two categories: 1.) potential sinkholes and 2.) probable sinkholes. This study had a lower success rate (50 percent) for identifying sinkholes via LiDAR …
Effects Of Folding On Mineral Cpos In Gneiss: Implications For Lower Crustal Seismic Anisotropy, Alexia K. Sarnowsky
Effects Of Folding On Mineral Cpos In Gneiss: Implications For Lower Crustal Seismic Anisotropy, Alexia K. Sarnowsky
Wayne State University Theses
Isotropic seismic properties are not sufficient to distinguish between many rock types believed to make up the middle and lower continental crust. Seismic anisotropy is the directional dependence of seismic velocity, which we can use to improve our understanding of the composition and structure of the middle and lower continental crust. Our rationale is that seismic anisotropy in the middle and lower crust is controlled by the crystallographic preferred orientation (CPO) of minerals. The effects of folding on mineral CPO in a folded gneiss from the Coweeta Group in North Carolina is used for this study, and we should be …
A Small-Scale Water Budget Approach And Water Quality Assessment: A Case Study For Calderas Lake, Guatemala, Edrick Ramos
A Small-Scale Water Budget Approach And Water Quality Assessment: A Case Study For Calderas Lake, Guatemala, Edrick Ramos
Dissertations, Master's Theses and Master's Reports
Increases in water demand and urban development in Calderas community over the past decade have led to questions about the hydrology, water quality, quantity and sustainable management of Calderas Lake micro-basin. However, studies on baseline hydrology are limited for rural communities located inside volcanic origin watersheds of Guatemala. The scope of this study was to characterize the hydrology and establish a method to: 1) quantify a water budget, and 2) qualify the water quality of a lacustrine system that supply water for about 17,000 inhabitants on the state limits or rural Guatemala City. Mean annual rainfall and temperature at the …
Sea Lamprey Mating Pheromone Registered By U.S. Environmental Protection Agency As First Vertebrate Pheromone Biopesticide, Marc Gaden, Marisa Lubeck
Sea Lamprey Mating Pheromone Registered By U.S. Environmental Protection Agency As First Vertebrate Pheromone Biopesticide, Marc Gaden, Marisa Lubeck
United States Geological Survey: Publications
Ann Arbor, MI – The U.S. Environmental Protection Agency registered a sea lamprey mating pheromone, 3kPZS, as the first ever vertebrate pheromone biopesticide in late December, 2015. Like an alluring perfume, the mating pheromone is a scent released by male sea lampreys to lure females onto nesting sites. Research and development of the mating pheromone was funded by the Great Lakes Fishery Commission, with additional support from the Great Lakes Restoration Initiative, in collaboration with federal government, university, and private industry partners.
Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen
Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen
United States Geological Survey: Staff Publications
The authors documented gross and microscopic morphology of lesions in corals on 7 islands spanning western, southern, and eastern Micronesia, sampling 76 colonies comprising 30 species of corals among 18 genera, with Acropora, Porites, and Montipora dominating. Tissue loss comprised the majority of gross lesions sampled (41%), followed by discoloration (30%) and growth anomaly (29%). Of 31 cases of tissue loss, most lesions were subacute (48%), followed by acute and chronic (26% each). Of 23 samples with discoloration, most were dark discoloration (40%), with bleaching and other discoloration each constituting 30%. Of 22 growth anomalies, umbonate growth anomalies composed …
Bioaccessibility Tests Accurately Estimate Bioavailability Of Lead To Quail, W. Nelson Beyer, Nicholas T. Basta, Rufus L. Chaney, Paula F.P. Henry, David E. Mosby, Barnett A. Rattner, Kirk G. Scheckel, Daniel T. Sprague, John S. Weber
Bioaccessibility Tests Accurately Estimate Bioavailability Of Lead To Quail, W. Nelson Beyer, Nicholas T. Basta, Rufus L. Chaney, Paula F.P. Henry, David E. Mosby, Barnett A. Rattner, Kirk G. Scheckel, Daniel T. Sprague, John S. Weber
United States Geological Survey: Staff Publications
Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability …
A Personal Perspective On Searching For The Ivory-Billed Woodpecker: A 41-Year Quest, Paul W. Sykes Jr.
A Personal Perspective On Searching For The Ivory-Billed Woodpecker: A 41-Year Quest, Paul W. Sykes Jr.
United States Geological Survey: Staff Publications
I first learned about the Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, while attending high school in the mid-1950s. Patuxent wildlife biologists Brooke Meanley, Chandler (Chan) S. Robbins, and Robert (Bob) E. Stewart, Sr., visited me at my parents’ home in Norfolk, VA. I was the compiler of the Norfolk County Christmas Bird Count (which included the eastern portion of the Virginia sector of the Dismal Swamp). As part of that count, we had for several years been estimating populations of red-winged blackbirds (Agelaius phoeniceus) and common grackles (Quiscalus quiscula) in the millions. Patuxent was …
Patuxent’S Role In The Development Of The North American Breeding Bird Survey, John R. Sauer
Patuxent’S Role In The Development Of The North American Breeding Bird Survey, John R. Sauer
United States Geological Survey: Staff Publications
The North American Breeding Bird Survey (BBS) is a roadside survey of the breeding birds of North America. The BBS provides data from the contiguous United States, Alaska, southern and central Canada, and northern Mexico. Begun in 1966 by Chandler (Chan) S. Robbins at the U.S. Geological Survey (USGS) Patuxent Wildlife Research Center (Patuxent), and now jointly managed by Patuxent, the Canadian Wildlife Service, and the Mexican Commission for the Knowledge and Use of Biodiversity, the survey is conducted primarily in June along more than 5,000 roadside survey routes that are surveyed once each year. Volunteer observers drive the 39.4-kilometer …
Patuxent’S Long-Term Research On Wolves, David L. Mech
Patuxent’S Long-Term Research On Wolves, David L. Mech
United States Geological Survey: Staff Publications
The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …
A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt
A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt
United States Geological Survey: Staff Publications
The effects of climate change have wide-ranging impacts on wildlife species and recent studies indicate that birds’ spring arrival dates are advancing in response to changes in global climates. In this paper, we propose a spatio-temporal approach for comparing avian first arrival data for multiple species. As an example, we analyze spring arrival data for two long-distance migrants (Rubythroated Hummingbird Archilochus colubris; and Purple Martin Progne subis) in eastern North America from 2001–2010 using Citizen Science data. The proposed approach provides researchers with a tool to compare mean arrival dates while accounting for spatial and temporal variability. Our results show …
Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle
Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle
United States Geological Survey: Staff Publications
Human alteration of the global P cycle has led to widespread P loading in freshwater ecosystems. Much research has been devoted to the capacity of wetlands and lakes to serve as long-term sinks for P inputs from the watershed, but we know much less about the potential of headwater streams to serve in this role. We assessed storage and retention of P in biotic and abiotic compartments after an 8-y experimental P addition to a 1st-order stream in a Neotropical wet forest. Sediment P extractions indicated that nearly all P storage was in the form of Fe- and Al-bound P …
Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt
Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt
Electronic Theses and Dissertations
A cyclostratigraphic and geochemical analysis was conducted on the basal high resistivity zone of the Tuscaloosa Marine Shale to determine if orbital forcing is apparent in mineralogical data suites. Geochemical data suites obtained via x-ray diffraction from five cored wells located near the southern Mississippi/Louisiana border were used in the study. The results were used in concert with previously published insolation and biostratigraphic data and unpublished stable carbon isotope data to determine sedimentation rate, to identify and correlate the cretaceous oceanic anoxic event 2 (OAE 2) recovery period within the studied interval, and to determine the possible mechanisms of orbital …
Three Dimensional Thermobaric Modeling Of A Gas Hydrate System, Amanda Quigley Williams
Three Dimensional Thermobaric Modeling Of A Gas Hydrate System, Amanda Quigley Williams
Theses and Dissertations
Seismic imaging is recognized as the most cost effective method for identifying the presence of gas hydrate resources. The base of the gas hydrate stability zone is recognized by the presence of regionally extensive bottom simulating reflectors (BSR). However, in some areas such as the Gulf of Mexico, regionally extensive BSRs are not found. In such cases, an understanding of the thermobaric conditions may be used to determine the location of gas hydrates and the base of the gas hydrate stability zone. The aim of this research is to combine seismic velocity analysis and thermal modeling to predict the base …
Implications Of Hf-Nd Isotopes In West Philippine Basin Basalts For The Initiation And Early History Of The Izu-Bonin-Mariana Arc, Benjamin D. Hocking
Implications Of Hf-Nd Isotopes In West Philippine Basin Basalts For The Initiation And Early History Of The Izu-Bonin-Mariana Arc, Benjamin D. Hocking
Theses and Dissertations
Drilling at Site U1438, located immediately west of Kyushu-Palau Ridge (KPR), the site of IBM subduction initiation, penetrated 1,460 m of volcaniclastic sedimentary rock and 150 m of underlying basement. Biostratigraphic controls indicate a probable age for the oldest sedimentary rocks at around 55 Ma. This is close to the 48-52 Ma time period of IBM subduction initiation, based on studies in the forearc. There, the first products of volcanism are tholeiitic basalts termed FAB (forearc basalt), which are more depleted than average MORB and show subtle indicators of geochemical enrichment due to subduction. Site U1438 basement basalts share many …
Submarine Groundwater Discharge And The Configuration Of The Freshwater-Saltwater Interface At The Nearshore And Embayment Scales, Tyler Brandon Evans
Submarine Groundwater Discharge And The Configuration Of The Freshwater-Saltwater Interface At The Nearshore And Embayment Scales, Tyler Brandon Evans
Theses and Dissertations
Submarine groundwater discharge (SGD) rivals riverine discharge to the world’s oceans but remains poorly understood. Until the early 1990’s, geochemical budgets for the ocean were developed using material fluxes from rivers only. SGD has been shown to carry high concentrations of dissolved nutrients, metals and carbon. However, SGD is a difficult to measure, complex phenomenon driven by multiple physical processes. Groundwater flow and the resultant chemical exchange at the land-sea interface are heavily impacted by the hydrodynamic effects of mixing between variable-density fluids. In order to better understand SGD, investigations have focused on the configuration of the freshwater-saltwater interface in …
Delineation Of The Lower Permian Gas Sand Via Calibrated Avo And Pre-Stack Seismic Inversions In Majhol Field, Saudi Arabia, Abdullah Alhashel
Delineation Of The Lower Permian Gas Sand Via Calibrated Avo And Pre-Stack Seismic Inversions In Majhol Field, Saudi Arabia, Abdullah Alhashel
Theses and Dissertations
The lower Permian formation in the central region of Saudi Arabia is a key hydrocarbon siliciclastic reservoir. However, in Majhol field, the reservoir properties vary laterally due to diagenesis and facies changes. Conventional seismic interpretation has failed to map the heterogeneities of the reservoir properties that control the gas production of this field. Therefore, there was an opportunity to employ more advanced quantitative seismic techniques to delineate the productive gas sand facies in the field.
The Majhol field was initially planned to be developed as an unconventional tight reservoir. Well-1 was drilled based on conventional seismic interpretation on the crest …
Late Ordovician Tectonism In The North American Midcontinent: Constraints From U-Pb Detrital Zircon Geochronology, Daniel Nathan Meehan I
Late Ordovician Tectonism In The North American Midcontinent: Constraints From U-Pb Detrital Zircon Geochronology, Daniel Nathan Meehan I
Masters Theses
"Numerous sandstone filled depressions hosted in upper Cambrian to Middle Ordovociain dolostones in south-central Missouri have historically been identified as Pennsylvanian paleokarst structures. U-Pb detrital zircon geochronology is at odds the time of formation and sedimentological evidence challenges their classification. "Filled sink" deposits yield primary zircon age populations of 2.8-2.6 Ga (~50% of all analyzed grains), 1.2-1.1 Ga (~25%), 1.8-1.6 Ga (~15%) and 1.5-1.3 Ga (~10%). These zircon populations most likely originated from the Superior Craton and Midcontinent Rift and/or Grenville orogen, respectively. The Warrensburg and Moberly channel-fill sandstones of central Missouri were identified as good candidates for Pennsylvanian aged …
Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori
Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori
Masters Theses
"Through the analysis of both U-Pb and (U-Th)/He ages from detrital zircon grains we can constrain thermal histories by establishing ages which correspond to crystallization and exhumation events, respectively. This combined geo-/thermochronologic approach is used here to constrain the history of the polyphase Nacimiento fault. This fault traverses central and southern California and has accumulated at least 150 km of slip since Late Cretaceous time. Major displacements along the structure occurred between 75 and 56 Ma, with Neogene to Holocene strike-slip remobilization linked to the San Andreas fault system. Detrital zircon U-Pb geochronology from Franciscan subduction assemblages west of the …
Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck
Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck
Masters Theses
"The spatial distribution of fracture sets associated with buckle folds has been well documented in field studies. There are difficulties, however, in placing accurate constraints on the timing of the initiation of individual fracture sets during the deformation history of the fold under in-situ conditions. This study investigates specific conditions that give rise to the initiation of various fracture sets in the hinge and limb of a pericline, based on an analysis of the effective stress evolution during the processes of buckling and erosional unloading. A 3D finite element modeling approach is used to simulate the effective stress evolution in …
Fluid Flow Through Deformation Band, Huining Zhang
Fluid Flow Through Deformation Band, Huining Zhang
Masters Theses
"Cataclastic deformation bands, which are common in porous sandstone, have the potential to restrict fluid flow. Geological studies have shown that permeability of deformation band shear zones can be one to five orders of magnitude less than for the sandstone host rock. However, recent studies based on simplified analytical estimates have shown that fluid flow in jointed deformation bands may not be retarded since joints play an important role in conducting fluids. In this study, 2 dimensional finite element analysis (FEA) is used to simulate the total discharge flow rate through jointed deformations. Variations of single planar and conjugate jointed …
Seismic Anisotropy And Mantle Dynamics Beneath The Central And Western United States, Bin Yang
Seismic Anisotropy And Mantle Dynamics Beneath The Central And Western United States, Bin Yang
Doctoral Dissertations
"Various tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other seismic stations in the central and western United States (CWUS) provide a distinct opportunity to test different anisotropy-forming mechanisms. For the first part of the study, a total of 4138 pairs of well-defined shear wave splitting (SWS) parameters observed at 445 stations on the northern Great Plains show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating …
Portable X-Ray Fluorescence Measurement Viability In Organic Rich Soils: Pxrf Response As A Function Of Organic Matter Presence, Roozbeh Ravansari
Portable X-Ray Fluorescence Measurement Viability In Organic Rich Soils: Pxrf Response As A Function Of Organic Matter Presence, Roozbeh Ravansari
Wayne State University Theses
Portable X-Ray fluorescence provides a cost effective method for producing rapid geochemical data. With advancements in X-Ray generation and detection technology, pXRF has become feasible for use on pedologic materials. Factors affecting pXRF soil measurements such as heterogeneity, moisture content, object geometry, and matrix interferences are widely recognized. However, the influence of organic matter on pXRF soil measurements is poorly understood.
This study examined the influence of organic matter fraction on pXRF trace metal measurements in a soil matrix. Incremental addition of three organic matter surrogates (cellulose, graphite powder, and confectioner’s sugar) was used to investigate the influence of increasing …
Integration Of Deterministic And Stochastic Models In A 1,4-Dioxane Contaminated Glacial Aquifer System, Washtenaw County, Michigan, Lena Kristin Pappas
Integration Of Deterministic And Stochastic Models In A 1,4-Dioxane Contaminated Glacial Aquifer System, Washtenaw County, Michigan, Lena Kristin Pappas
Wayne State University Theses
Hybrid models incorporating stochastic variability within a deterministic hydrostratigraphic framework provide an effective way to assess uncertainty in flow and transport model predictions. This study evaluated the distribution of groundwater flow and contaminant transport pathways in two ensembles of spatially variable hydraulic conductivity (K) distributions. The models comprised a 360 ft-thick sequence of Pleistocene glacial sediments in in an approximately 8 mi2 area across Washtenaw County, Michigan. Conditioned K fields were generated using Sequential Gaussian Simulation (SGS) and Sequential Indicator Simulation (SIS) constructed using indicator classes based on natural gamma ray logs from 77 monitoring wells. K fields were modeled …