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Articles 22051 - 22080 of 29955
Full-Text Articles in Geology
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.
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, …
Application Of Integrated Reservoir Geomechanics For Well Planning Of High-Angled Wells In A Mature Oil Field, Ahmed K. Abbas, Ralph E. Flori, Yousif M.B. Al-Asadi, Mortadha Alsaba, Nasser A. Al-Hamad
Application Of Integrated Reservoir Geomechanics For Well Planning Of High-Angled Wells In A Mature Oil Field, Ahmed K. Abbas, Ralph E. Flori, Yousif M.B. Al-Asadi, Mortadha Alsaba, Nasser A. Al-Hamad
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Zubair oil reservoir has a significant potential to contribute to the petroleum supply in Iraq. Drilling highly deviated wells is a commonly used approach to enhance the production in mature fields. Drilling these wells in the Zubair Formation has been a challenge due to severe wellbore instability issues. This study presents how integrated reservoir geomechanics was used for efficient well planning and safe drilling of nearly horizontal wells (75° Inclination) through Zubair depleted sandstone oil reservoir. In this study, an integrated workflow was implemented mainly to build a geomechanical model using offset well data. The in-situ principal stresses and their …
Learning From Experience: An Automatic Ph Neutralization System Using Hybrid Fuzzy System And Neural Network, Ethar H.K. Alkamil, Seaar Al-Dabooni, Ahmed K. Abbas, Ralph Flori, Donald C. Wunsch
Learning From Experience: An Automatic Ph Neutralization System Using Hybrid Fuzzy System And Neural Network, Ethar H.K. Alkamil, Seaar Al-Dabooni, Ahmed K. Abbas, Ralph Flori, Donald C. Wunsch
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
In oil and gas industry, the pH level is one of the most important indicators of mud contamination while drilling. Although the process has simple components, the pH neutralization process is complicated in the mud circulation system. This difficulty is due to the high nonlinearity of the process. In this paper, the fuzzy neural network (FNN) is integrated to the fuzzy logic controller (FLC) to create a system which identifies pH fluctuation into a drilling mud system, assesses and signals its severity. And then, it automatically actuates a chemical treating fluids valve (CTFV), such as Caustic Soda (CS), for neutralizing …
Using Managed Pressure Drilling To Reduce Stuck Pipe Problem, Ethar H.K. Alkamil, Husam R. Abbood, Ralph E. Flori, George Medley, Sagar Nauduri, Mortadha Alsaba
Using Managed Pressure Drilling To Reduce Stuck Pipe Problem, Ethar H.K. Alkamil, Husam R. Abbood, Ralph E. Flori, George Medley, Sagar Nauduri, Mortadha Alsaba
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Differences between mud pressure in a wellbore and pore pressure in high permeability rocks can lead to differential sticking, particularly when drilling deviated wells and encountering mud losses. Several solutions, all challenging, can be used to address this problem, where the conventional mitigation method of managing the mud weight (MW) is often used. However, managed pressure drilling (MPD) offers a promising solution with a positive risk-adjusted cost and other benefits. Wells in the E oilfield in southern Iraq are typically drilled overbalanced and therefore often experience a high percentage of non-productive time (NPT) due to differential sticking. This study evaluates …
A Novel Ultra-Low Interfacial Tension Nanofluid For Enhanced Oil Recovery In Super-Low Permeability Reservoirs, Derong Xu, Baojun Bai, Ziyu Meng, Qiong Zhou, Zhe Li, Yao Lu, Hairong Wu, Jirui Hou, Wanli Kang
A Novel Ultra-Low Interfacial Tension Nanofluid For Enhanced Oil Recovery In Super-Low Permeability Reservoirs, Derong Xu, Baojun Bai, Ziyu Meng, Qiong Zhou, Zhe Li, Yao Lu, Hairong Wu, Jirui Hou, Wanli Kang
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The exploration and development of super-low permeability reservoirs have become a global focus in recent years. However, conventional flooding systems commonly face problems of high injection pressure and poor displacement efficiency in super-low permeability reservoirs. Thus, it is imperative to find new flooding agents that tackle such problems. In this study, a novel ultra-low interfacial tension (IFT) nanofluid was formulated, consisting of surfactants to achieve ultra-low IFT and silica nanoparticles to reduce injection pressure. The compatibility test between the surfactants and silica nanoparticles in 10,000 mg/L NaCl solution at 90 °C was conducted to ensure their adaption to harsh reservoir …
Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii
Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii
Contract Reports--KGS
The Newport 7.5-minute quadrangle is located in the Outer Bluegrass physiographic province (McFarlan, 1943) in the Greater Cincinnati metropolitan area of northern Kentucky and includes parts of Kenton and Campbell Counties. Topography is characterized by a relatively broad expanse of upland with moderate relief that is bounded by the Ohio River Valley, Licking River Valley, and Fourmile Creek. Gibbons (1973) mapped the bedrock geology of this quadrangle, which was later digitized by Sparks (2002). The entire quadrangle is underlain by horizontal Ordovician limestone and shale, consisting of the Point Pleasant Formation, Kope Formation, Fairview Formation, Bellevue Tongue of the Grant …
Surficial Geologic Map Of The Patriot 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Steven L. Martin
Surficial Geologic Map Of The Patriot 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Steven L. Martin
Contract Reports--KGS
The Patriot 7.5-minute quadrangle is located in Boone, Gallatin, and Grant Counties of northern Kentucky in the Outer Bluegrass physiographic province (McFarlan, 1943). Broad to narrow ridges, steep hillsides, and the Ohio River Valley characterize the topography of the quadrangle. The Ohio River has been made navigable by a series of high-level dams, and the Markland Locks and Dam controls the river level in this area (Ray, 1974). The bedrock geology, originally mapped by Swadley (1969), consists, from oldest to youngest, of the Point Pleasant Formation, the Kope Formation, the Fairview Formation, the Bellevue Tongue of the Grant Lake Limestone, …
Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb
Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb
Report of Investigations--KGS
The demolition by implosion of the Capital Plaza Tower in downtown Frankfort provided an opportunity to record seismic waves from a known source of seismic energy in order to observe local ground-motion amplification and resonance within the underlying unconsolidated sediment. The Kentucky Geological Survey deployed three strong-motion accelerographs at approximately equal distances around the tower to record ground motions induced by its collapse. The KGS instruments were installed at sites with different underlying geology: one on bedrock and two on Kentucky River Valley unconsolidated sediments.
Using images captured by a high-speed video camera, with timing synchronized with the clock of …
Calcic Paleosols In A Stratigraphic Context From Quaggasfontein, Eastern Cape Province, South Africa: Correlations In The Wapadsberg Pass Area And Implications For Late Permian Climate, Kaci B. Kus
Honors Theses
The Karoo Basin, South Africa, contains a reportedly continuous stratigraphic record spanning the terrestrial vertebrate extinction event equated with the Permian-Triassic boundary (PTB) in the marine record. The current hypothesis links this major loss in biodiversity and vertebrate turnover to a global change in climate towards aridification. Rapid climate change is interpreted to be reflected in continental rocks by a changeover from (1) greenish (Permian) to reddish (Triassic) mudrock, (2) a transition in the river architectures from meandering to braided regimes, and (3) wetland to calcic-bearing paleosols. Here, we present geochemical results on a 1.3-meter calcic paleoVertisol interval found ~34 …
Evidence For Ephemeral Middle Eocene To Early Oligocene Greenland Glacial Ice And Pan-Arctic Sea Ice, Aradhna Tripati, Dennis Darby
Evidence For Ephemeral Middle Eocene To Early Oligocene Greenland Glacial Ice And Pan-Arctic Sea Ice, Aradhna Tripati, Dennis Darby
OES Faculty Publications
Earth's modern climate is defined by the presence of ice at both poles, but that ice is now disappearing. Therefore understanding the origin and causes of polar ice stability is more critical than ever. Here we provide novel geochemical data that constrain past dynamics of glacial ice on Greenland and Arctic sea ice. Based on accurate source determinations of individual ice-rafted Fe-oxide grains, we find evidence for episodic glaciation of distinct source regions on Greenland as far-ranging as ~68°N and ~80°N synchronous with ice-rafting from circum-Arctic sources, beginning in the middle Eocene. Glacial intervals broadly coincide with reduced CO2 …
Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle
Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle
OES Faculty Publications
The ~ 3.48 billion-year-old Dresser Formation, Pilbara Craton, Western Australia, is a key geological unit for the study of Earth's earliest life and the habitats it occupied. Here, we describe a new suite of spheroidal to lenticular microstructures that morphologically resemble some previously reported Archean microfossils. Correlative microscopy shows that these objects have a size distribution, wall ultrastructure, and chemistry that are incompatible with a microfossil origin and instead are interpreted as pyritized and silicified fragments of vesicular volcanic glass. Organic kerogenous material is associated with much of the altered volcanic glass; variable quantities of organic carbon line or fill …
Giant Plagioclase In The Steens Basalt, Se Oregon: Cumulate Entrainment Revealed By Textural And In Situ Chemical Analysis, Conner H. Toth
Giant Plagioclase In The Steens Basalt, Se Oregon: Cumulate Entrainment Revealed By Textural And In Situ Chemical Analysis, Conner H. Toth
All Master's Theses
Many of the lava flows comprising the Steens Basalt in SE Oregon, the oldest and most mafic formation of the Columbia River Basalt Group (CRBG), contain exceptionally large (up to 5 cm) and abundant (up to 40 modal %) plagioclase crystals. This thesis presents a model for giant plagioclase formation in a complex system that integrates petrographic and in situ plagioclase compositional analyses with whole-rock data and computational modeling to explain systematic textural and chemical differences between plagioclase of the lower and upper Steens Basalt sub-sections. Lower Steens plagioclase are typically more chemically homogenous than upper Steens plagioclase and exhibit …
The Origin Of Dark Mats At The Sunrise Ridge Borrow Pit Site (45pi408) Mount Rainier National Park, Washington, Sean Stcherbinine
The Origin Of Dark Mats At The Sunrise Ridge Borrow Pit Site (45pi408) Mount Rainier National Park, Washington, Sean Stcherbinine
All Master's Theses
The Sunrise Ridge Borrow Pit Site is a precontact archaeological site located in the upland forest soils of Mount Rainier National Park. Site stratigraphy is complicated, consisting of tephra deposits from mostly known origins that are intercalated with dark sediments of unknown origin, referred to here as dark mats. Precontact occupation has been split previously into two components based on the ambiguous depositional history of the dark mats, notably their unknown parent material, depositional environment, and relationship with adjacent tephra strata. Stratigraphic samples from excavation units, features, and one off-site excavation unit was used to investigate these data gaps. Grain …
Geochronological And Geochemical Constraints On The Origin Of The Cartoogechaye Terrane, Western North Carolina: Implications For The Late Precambrian To Early Paleozoic Evolution Of The Eastern Laurentian Margin, Kevin B. Walsh Jr.
Theses and Dissertations--Earth and Environmental Sciences
The Cartoogechaye terrane (CT) is an enigmatic migmatite terrane within the Central Blue Ridge province of the southern Appalachians. Previous work identified exotic Pb isotope compositions within the CT (Quinn, 2012). More recent studies that mapped the extent of potentially exotic metaigneous lithologies yield U-Pb zircon ages consistent with a native Laurentian margin metasedimentary origin (Larkin, 2016). This study focused on the possible extent of similar lithologies in the Clyde quadrangle and provides further constraints on the crustal affinity of the CT. The Clyde quadrangle consists of four distinct lithologic packages: the CT, Ashe metamorphic suite, Great Smoky Group, and …
Climate-Change-Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters, G. T. Mitchum
Climate-Change-Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters, G. T. Mitchum
CCPO Publications
Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change-driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y2. Coupled with the average climate-change-driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections.
Assessing The Impact Of The Conservation Reserve Program On Honey Bee Health, Otto, C.R.V., O'Dell, S., Bryant, R.B., Euliss, N.H., Bush
Assessing The Impact Of The Conservation Reserve Program On Honey Bee Health, Otto, C.R.V., O'Dell, S., Bryant, R.B., Euliss, N.H., Bush
United States Geological Survey: Publications
Insect pollinators are critically important for maintaining U.S. food production and ecosystem health. The upper Midwest is home to more than 40 percent of all U.S. honey bee colonies and is considered by many beekeepers to be America’s last beekeeping refuge. Beekeepers come to this region because their honey bees require high-quality grassland and bee-friendly agricultural crops to make honey and to improve bee health. Agricultural grassland, such as those enrolled in the Conservation Reserve Program (CRP), support flowers that provide bees with the pollen and nectar they need. In 2014, the U.S. Department of Agriculture (USDA) and the U.S. …
Adaptive Management In Native Grasslands Managed By The U.S. Fish And Wildlife Service—Implications For Grassland Birds, Lawrence D. Igl, Welsey E. Newton, Todd A. Grant, Cami S. Dixon
Adaptive Management In Native Grasslands Managed By The U.S. Fish And Wildlife Service—Implications For Grassland Birds, Lawrence D. Igl, Welsey E. Newton, Todd A. Grant, Cami S. Dixon
United States Geological Survey: Publications
Burning and grazing are natural processes in native prairies that also serve as important tools in grassland management to conserve plant diversity, to limit encroachment of woody and invasive plants, and to maintain or improve prairies. Native prairies managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region of the northern Great Plains have been extensively invaded by nonnative, cool-season species of grasses. These invasions were believed to reflect a common management history of long-term rest and little or no defoliation by natural processes (burning and grazing). To address the challenges associated with these invasive species, …
Evaluating Restored Tidal Freshwater Wetlands, Andrew H. Baldwin1,, Richard S. Hammerschlag, Donald R. Cahoon
Evaluating Restored Tidal Freshwater Wetlands, Andrew H. Baldwin1,, Richard S. Hammerschlag, Donald R. Cahoon
United States Geological Survey: Staff Publications
Tidal freshwater wetlands are recognized as highly productive coastal wetlands that support diverse assemblages of plants and animals and complex biogeochemical cycles (in this book, see Chapter 18 by Whigham et al. and Chapter 19 by Megonigal and Neubauer). Many tidal freshwater wetlands and their associated ecosystem services have been damaged or destroyed by urbanization, agriculture, and other human activities (Baldwin, 2004; Barendregt et al., 2006). Increasing recognition of the value of remaining wetlands and environmental regulations requiring wetland mitigation (i.e., enhancement, creation, or restoration of wetlands to compensate for wetland losses; Kentula, 2000) has driven the restoration of all …
The Global Food-Energy-Water Nexus, Paolo D’Odorico, Kyle Frankel Davis, Lorenzo Rosa, Joel A. Carr, Davide Chiarelli, Jampel Dell’Angelo, Jessica Gephart, Graham K. Macdonald, David A. Seekell, Samir Suweis, Maria Cristina Rulli
The Global Food-Energy-Water Nexus, Paolo D’Odorico, Kyle Frankel Davis, Lorenzo Rosa, Joel A. Carr, Davide Chiarelli, Jampel Dell’Angelo, Jessica Gephart, Graham K. Macdonald, David A. Seekell, Samir Suweis, Maria Cristina Rulli
United States Geological Survey: Staff Publications
Water availability is a major factor constraining humanity’s ability to meet the future food and energy needs of a growing and increasingly affluent human population. Water plays an important role in the production of energy, including renewable energy sources and the extraction of unconventional fossil fuels that are expected to become important players in future energy security. The emergent competition for water between the food and energy systems is increasingly recognized in the concept of the “food-energy-water nexus.” The nexus between food and water is made even more complex by the globalization of agriculture and rapid growth in food trade, …