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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 2018 Native Prairie Adaptive Management

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 2018 Missouri University of Science and Technology

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 2018 School of Civil and Construction Engineering, Oregon State University

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 2018 University of Kentucky

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 2018 Missouri University of Science and Technology

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 2018 Michigan Technological University

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 2018 University of Kentucky

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 2018 Harvard University

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 2018 Portland State University

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 2018 Arkansas Tech University

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 2018 Murray State University

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 2018 Missouri University of Science and Technology

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 …


Trace Element And Isotopic Fingerprinting Of Olivine Phenocrysts As Recorders Of Magmatic Processes In The Golden Trout Volcanic Field, Kern Plateau, Ca, Mark E. Szymanski 2018 Humboldt State University

Trace Element And Isotopic Fingerprinting Of Olivine Phenocrysts As Recorders Of Magmatic Processes In The Golden Trout Volcanic Field, Kern Plateau, Ca, Mark E. Szymanski

Cal Poly Humboldt theses and projects

Quaternary mafic volcanism in the western Basin and Range and in the southeastern Sierra Nevada is largely controlled by extensional stresses that promote magma generation through decompression melting of the lithospheric and asthenospheric mantle. Where volcanism occurs in the Sierra Nevada, like at the Golden Trout Volcanic Field GTVF), the eruption rate, number of vents, and eruption volume is an order of magnitude less than at neighboring Basin and Range volcanic fields such as the Big Pine Volcanic Field (BPVF). To determine the factors that cause these differences in adjacent and contemporaneous volcanic fields, I sampled rocks from both fields …


Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond III 2018 Kentucky Geological Survey

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 …


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