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Trends In Streamflow And Precipitation For Selected Sites In The Elkhorn River Basin And In Streamflow In The Salt Creek And Platte River Basins, Nebraska, 1961–2011, Benjamin J. Dietsch, Kellan R. Strauch 2020 U.S. Geological Survey

Trends In Streamflow And Precipitation For Selected Sites In The Elkhorn River Basin And In Streamflow In The Salt Creek And Platte River Basins, Nebraska, 1961–2011, Benjamin J. Dietsch, Kellan R. Strauch

United States Geological Survey: Publications

To better understand the streamflow trends at the streamgages in the Elkhorn River Basin in Nebraska, the U.S. Geological Survey (USGS) in cooperation with the Lower Elkhorn Natural Resources District further investigated streamflow trends at the eight streamgages on the Elkhorn River, Salt Creek, and the Lower Platte River that indicated a positive trend in streamflow characteristics and analyzed precipitation trends in the four basins upstream from the Elkhorn River Basin streamgages. An analysis of four streamgages in the Elkhorn River Basin, one streamgage in Salt Creek Basin, and three streamgages in the Lower Platte River Basin that had previously …


Modeling Escherichia Coli In The Missouri River Near Omaha, Nebraska, 2012–16, Brenda K. Densmore, Brent M. Hall, Matthew T. Moser 2020 U.S. Geological Survey

Modeling Escherichia Coli In The Missouri River Near Omaha, Nebraska, 2012–16, Brenda K. Densmore, Brent M. Hall, Matthew T. Moser

United States Geological Survey: Publications

The city of Omaha, Nebraska, has a combined sewer system in some areas of the city. In Omaha, Nebr., a moderate amount of rainfall will lead to the combination of stormwater and untreated sewage or wastewater being discharged directly into the Missouri River and Papillion Creek and is called a combined sewer overflow (CSO) event. In 2009, the city of Omaha began the implementation of their Long Term Control Plan (LTCP) to mitigate the effects of CSOs on the Missouri River and Papillion Creek. As part of the LTCP, the city partnered with the U.S. Geological Survey (USGS) in 2012 …


Annotated Bibliography Of Scientific Research On Greater Sage-Grouse Published From 2015 To 2019, Sarah K. Carter, Robert S. Arkle, Heidi L. Bencin, Benjamin R. Harms, Daniel J. Manier, Aaron N. Johnston, Susan L. Phillips, Steven E. Hanser, Zachary H. Bowen 2020 USGS

Annotated Bibliography Of Scientific Research On Greater Sage-Grouse Published From 2015 To 2019, Sarah K. Carter, Robert S. Arkle, Heidi L. Bencin, Benjamin R. Harms, Daniel J. Manier, Aaron N. Johnston, Susan L. Phillips, Steven E. Hanser, Zachary H. Bowen

United States Geological Survey: Publications

The greater sage-grouse (Centrocercus urophasianus; hereafter GRSG) has been a focus of scientific investigation and management action for the past two decades. The 2015 U.S. Fish and Wildlife Service listing determination of “not warranted” was in part due to a large-scale collaborative effort to develop strategies to conserve GRSG populations and their habitat and to reduce threats to both. New scientific information augments existing knowledge and can help inform updates or modifications to existing plans for managing GRSG and sagebrush ecosystems. However, the sheer number of scientific publications can be a challenge for managers tasked with evaluating and …


Groundwater Availability Of The Northern High Plains Aquifer In Colorado, Kansas, Nebraska, South Dakota, And Wyoming, Steven M. Peterson, Jonathan P. Traylor, Moussa Guira 2020 U.S. Geological Survey

Groundwater Availability Of The Northern High Plains Aquifer In Colorado, Kansas, Nebraska, South Dakota, And Wyoming, Steven M. Peterson, Jonathan P. Traylor, Moussa Guira

United States Geological Survey: Publications

The Northern High Plains aquifer underlies about 93,000 square miles of Colorado, Kansas, Nebraska, South Dakota, and Wyoming and is the largest subregion of the nationally important High Plains aquifer. Irrigation, primarily using groundwater, has supported agricultural production since before 1940, resulting in nearly $50 billion in sales in 2012. In 2010, the High Plains aquifer had the largest groundwater withdrawals of any major aquifer system in the United States.Nearly one-half of those withdrawals were from the Northern High Plains aquifer, which has little hydrologic interaction with parts of the aquifer farther south. Land-surface elevation ranges from more than 7,400 …


Vertical Land Displacement Rates And Uncertainty In Hampton Roads, Va [Dataset], Brett Buzzanga, David P. S. Bekaert, Ben D. Hamlington, Simran S. Sangha 2020 Old Dominion University

Vertical Land Displacement Rates And Uncertainty In Hampton Roads, Va [Dataset], Brett Buzzanga, David P. S. Bekaert, Ben D. Hamlington, Simran S. Sangha

CCPO Data Sets

These data contain vertical rates (mm/yr) of surface land displacements and their associated uncertainties from 2015-03-15 to 2019-06-01.

They are associated with Buzzanga, B. A., Bekaert, D. P. S., Hamlington, B. D., and Sanga, S. (2020), "Towards Sustained Monitoring of Subsidence at the Coast Using InSAR and GNSS: An Application in Hampton Roads, Virginia. Geophysical Research Letters.


Joint Simulation Of Continuous And Categorical Variables For Mineral Resource Modeling And Recoverable Reserves Calculation, Sentle Augustinus Hlajoane 2020 Michigan Technological University

Joint Simulation Of Continuous And Categorical Variables For Mineral Resource Modeling And Recoverable Reserves Calculation, Sentle Augustinus Hlajoane

Dissertations, Master's Theses and Master's Reports

Spatial variability and uncertainty of continuous variables (grade) and categorical variables (rock-types) in mineral evaluation significantly impact the economics of mining projects. The conventional approach of simulating grades using deterministic rock- types is problematic since spatial variability, and uncertainty of grades at rock-type contacts are not well captured in deposits where the grade changes gradually between rock-types. Therefore, jointly simulating these variables can improve confidence (reduce uncertainty) in a resource model. Also, resource classification and recoverable reserve calculation can significantly improve the understanding of the deposit and its economic viability. This research utilized the Plural-Gaussian geostatistical simulation to jointly simulate …


Testing Interpretations Of The Displacement Magnitude Of The Teton Fault And Uplift Of The Teton Range, Wyoming With Integrated Flexural-Kinematic And Thermal Modeling, Autumn Helfrich 2020 University of Kentucky

Testing Interpretations Of The Displacement Magnitude Of The Teton Fault And Uplift Of The Teton Range, Wyoming With Integrated Flexural-Kinematic And Thermal Modeling, Autumn Helfrich

Theses and Dissertations--Earth and Environmental Sciences

The Teton fault is a range-front normal fault in northwestern Wyoming. Previous estimates of the maximum displacement (Dmax) on the Teton fault cover a wide range (2 - 11 km). Discrepancies also exist regarding the slip onset timing, which spans 2 - 13 Ma. To address these discrepancies, the exhumation history of the Teton Range is here investigated using forward flexural-kinematic (Move) and thermal-kinematic (Pecube) models that can be compared with previously reported apatite fission track (AFT) and apatite (U-Th)/He (AHe) ages from Mount Moran, which has been previously hypothesized to represent the …


The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross 2020 University of Colorado, Boulder

The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 Cel., the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to understand the drivers …


Northward Migration Of The Oregon Forearc On The Gales Creek Fault, Ray E. Wells, Richard J. Blakely, Sean Bemis 2020 Portland State University

Northward Migration Of The Oregon Forearc On The Gales Creek Fault, Ray E. Wells, Richard J. Blakely, Sean Bemis

Geology Faculty Publications and Presentations

The Gales Creek fault (GCF) is a 60-km-long, northwest-striking dextral fault system (west of Portland, Oregon) that accommodates northward motion and uplift of the Oregon Coast Range. New geologic mapping and geophysical models confirm inferred offsets from earlier geophysical surveys and document ∼12 km of right-lateral offset of a basement high in Eocene Siletz River Volcanics since ca. 35 Ma and ∼8.8 km of right-lateral separation of Miocene Columbia River Basalt at Newberg, Oregon, since 15 Ma (∼0.62 ± 0.12 mm/yr, average long-term rate). Relative uplift of Eocene Coast Range basalt basement west of the fault zone is at least …


Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila 2020 California Water Science Center, United States Geological Survey

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …


Emulsion Stability Of Heavy Oil With Surfactants And Nanoparticles, Zainab Abdulmohsein, Baojun Bai, Parthasakha Neogi 2020 Missouri University of Science and Technology

Emulsion Stability Of Heavy Oil With Surfactants And Nanoparticles, Zainab Abdulmohsein, Baojun Bai, Parthasakha Neogi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The recovered crude oil is often in form of an emulsion and the recovery is cut off when water to oil ratio exceeds a certain amount. The emulsions vary from water-in-oil to oil-in-water and the step that follows is to coalesce droplets to get two continuous liquids. Difficulties arise when the oil contains emulsifiers. There are naturally occurring surfactants, or the oil recovered is by enhanced oil recovery techniques which have additives that stabilize the droplets. We have considered below a heavy oil (viscosity 650-750 mPa.s) containing one of the three surfactants: a nonionic surfactant or a cationic surfactant or …


Soil Fatigue From Induced Seismicity, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz 2020 Missouri University of Science and Technology

Soil Fatigue From Induced Seismicity, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Induced seismicity and the effects on civil engineering systems are not completely understood and infrequently studied. One specific area that is not well known is soil fatigue which includes factors such as understanding the natural conditions of the subsurface as well as operational parameters under short duration impulse loads. With the increase of Geo induced seismic activity, soil fatigue becomes of greater concern to structures in the vicinity of this seismic load. The foundations of these structures can be affected by impulse loads which can ultimately cause failure. The lack of quantitative data puts the reliability of these civil engineering …


Corrigendum To "Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T.F. Wong, Xiaoju Pan 2020 Old Dominion University

Corrigendum To "Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T.F. Wong, Xiaoju Pan

OES Faculty Publications

No abstract provided.


Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart 2020 Murray State University

Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart

Murray State Theses and Dissertations

Floodplains can store large amounts of soil organic carbon (SOC) despite covering a small fraction of the global land area. Since these valley-bottom landforms build through the action of flooding, the century to millennial-scale record of overbank deposition could be important in understanding controls on deep (>30 cm) SOC storage. Yet, the influence of flood history and landform development on carbon content is surprisingly not well known. I use a combined geological and pedological approach to characterize the sedimentation, soil development, and SOC of fluvial terraces along an impounded reach of the humid-subtropical Tennessee River valley, U.S.A. The standardized …


The Enigmatic Curvature Of Central Iberia And Its Puzzling Kinematics, Daniel Pastor-Galan, Gabriel Gutierrez-Alonso, Arlo Brandon Weil 2020 Tohoku University

The Enigmatic Curvature Of Central Iberia And Its Puzzling Kinematics, Daniel Pastor-Galan, Gabriel Gutierrez-Alonso, Arlo Brandon Weil

Geology Faculty Research and Scholarship

The collision between Gondwana and Laurussia that formed the latest supercontinent, Pangea, occurred during Devonian to early Permian times and resulted in a largescale orogeny that today transects Europe, northwest Africa, and eastern North America. This orogen is characterized by an "S" shaped corrugated geometry in Iberia. The northern curve of the corrugation is the well-known and studied Cantabrian (or Ibero-Armorican) Orocline and is convex to the east and towards the hinterland. Largely ignored for decades, the geometry and kinematics of the southern curvature, known as the Central Iberian curve, are still ambiguous and hotly debated. Despite the paucity of …


Isotopic And Geochemical Tracers Of Groundwater Flow In The Shivwits Plateau, Grand Canyon National Park, Jonathan W. Wilson 2020 University of Kentucky

Isotopic And Geochemical Tracers Of Groundwater Flow In The Shivwits Plateau, Grand Canyon National Park, Jonathan W. Wilson

Theses and Dissertations--Earth and Environmental Sciences

As the impacts of global climate change on water resources continue to become more apparent, proper understanding and management of groundwater resources will be needed as supplies become more strained. Traditional methods of characterizing groundwater systems are time-intensive, costly, and can be difficult to complete in remote areas. Using ambient geochemical tracers from discrete sampling could aid in characterizing spring systems through determining flow paths, recharge areas, and carbon cycling. However, using discrete seasonal samples to understand the hydrogeology of complex, mixed-lithology aquifers has not been extensively examined. Here we explore using δ13C of dissolved organic carbon (DOC), …


“The Tale Of 3,000 Zircons”: An Investigation Of Grenville Sedimentation In Amazonia Using U/Pb Detrital Zircon Geochronology, Felicia R. Harris 2020 University of Kentucky

“The Tale Of 3,000 Zircons”: An Investigation Of Grenville Sedimentation In Amazonia Using U/Pb Detrital Zircon Geochronology, Felicia R. Harris

Theses and Dissertations--Earth and Environmental Sciences

The continental collision between Laurentia and Amazonia that generated Rodinia and the Grenville Orogen is proposed to be one of the largest, hottest and longest-lived orogens in Earth history. Subsequent erosion and weathering led to a mountain range’s worth of sediment recycled into clastic systems across North America, otherwise known as the “Great Grenville Sedimentation Event”. The Sunsas orogeny in Amazonia is correlative to the Grenville in North America and is proposed to be the result of final Rodinian collision at 1200-1000 Ma. Despite the connection between the two ranges and the robust sedimentary record in North America, little work …


Detecting Groundwater Discharge In The Clark Fork River Near Stone Container Using Spectral Alpha Decay Detection For Dissolved Radon In Surface Water Samples Abstract, Daniel William Forsland 2020 University of Montana

Detecting Groundwater Discharge In The Clark Fork River Near Stone Container Using Spectral Alpha Decay Detection For Dissolved Radon In Surface Water Samples Abstract, Daniel William Forsland

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Radon-222 (222Rn) was measured along 8.7 kilometers of the Clark Fork River, between Harper’s Bridge and Frenchtown, MT. Twelve water samples were taken along the stretch. Samples 1 through 4 and 10 through 12 were collected on a 1 km interval, samples 5 through 9 were taken on a 500 meter interval. Samples were analyzed for dissolved 222Rn using a RAD7 spectral alpha decay detector. Instream 222Rn was modeled to quantify groundwater discharge to the river. Literature on the Missoula Valley aquifer was analyzed, revealing an alluvial aquifer system to the east consisting of interbedded gravel, …


Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano 2020 Michigan Technological University

Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano

Dissertations, Master's Theses and Master's Reports

The study was focused on the Anak Krakatau sector collapse that occurred on 22 December 2018 in the Sunda Strait (Indonesia). The goal of the study was to monitor and analyze changes of the volcanic edifice and to try to understand causes that may have predisposed and triggered the sector collapse.

The use of different remote sensing techniques allowed the acquisition of thermal data, SO2 emission data, structural data and the identification and analysis of the eruptive events that occurred on Anak Krakatau in the period from 1° January 2016 to 28 February 2019. The acquisition of 1221 thermal …


Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. McGuire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch 2020 U.S. Geological Survey

Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. Mcguire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch

United States Geological Survey: Publications

The Mississippi River Valley alluvial (MRVA) aquifer is an important surficial aquifer in the Mississippi Alluvial Plain (MAP) area. The aquifer is generally considered to be an unconfined aquifer (fig. 1; Clark and others, 2011), and withdrawals are primarily used for irrigation (Maupin and Barber, 2005). These groundwater withdrawals have resulted in substantial areas of water-level decline in parts of the aquifer. Concerns about water-level declines and the sustainability of the MRVA aquifer have prompted the U.S. Geological Survey (USGS), as part of the USGS Water Availability and Use Science Program and with assistance from other Federal, State, and local …


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