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Integrated Ocean, Earth, And Atmospheric Observations For Resilience Planning In Hampton Roads, Virginia, Jon Derek Loftis, Molly Mitchell, Larry Atkinson, Ben Hamlington, Tom Allen, David Forrest, Teresa Updyke, Navid Tahvildari, David Bekaert, Mark Bushnell Jan 2018

Integrated Ocean, Earth, And Atmospheric Observations For Resilience Planning In Hampton Roads, Virginia, Jon Derek Loftis, Molly Mitchell, Larry Atkinson, Ben Hamlington, Tom Allen, David Forrest, Teresa Updyke, Navid Tahvildari, David Bekaert, Mark Bushnell

CCPO Publications

Building flood resilience in coastal communities requires a precise understanding of the temporal and spatial scales of inundation and the ability to detect and predict changes in flooding. In Hampton Roads, the Intergovernmental Pilot Project’s Scientific Advisory Committee recommended an integrated network of ocean, earth, and atmospheric data collection from both private and public sector organizations that engage in active scientific monitoring and observing. Since its establishment, the network has grown to include monitoring of water levels, land subsidence, wave measurements, current measurements, and atmospheric conditions. High-resolution land elevation and land cover data sets have also been developed. These products …


Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle Jan 2018

Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle

All Master's Theses

Low summer river base flow places a strain on natural and economic resources of the Eastern Cascades. A major contributor to stream flow in this region is snow pack which has declined over the past few decades because of a warming climate. In addition, glacial runoff, which contributes significantly to base flow in summer dry periods, will diminish from glacial recession. However, rock glaciers, because their internal ice (i.e., permafrost) is insulated by an outer debris layer, react slowly to climate change, thus acting as sinks for ice and liquid water storage in mountain environments. This study utilized ground penetrating …


Two Post-Glacial Sagebrush Steppe Fire Records At The Wildland-Urban Interface, Eastern Cascades, Washington, Dusty Pilkington Jan 2018

Two Post-Glacial Sagebrush Steppe Fire Records At The Wildland-Urban Interface, Eastern Cascades, Washington, Dusty Pilkington

All Master's Theses

Recent increases in large fires in the rapidly developing wildland-urban interface (WUI) areas of central Washington, where development intermixes with wildland fuels, contribute to federal firefighting costs exceeding of $1 billion annually. In addition, cheatgrass (Bromus tectorum) invasion and anthropogenic-caused warming shorten fire return intervals while lengthening fire seasons. These climatic, ecological, economic, and social factors combine with fuel accumulation resulting from historic fire suppression to threaten lives and property in the WUI. To plan for safe growth in WUI areas, long-term fire histories are needed to expand understanding of past fire regimes in an understudied ecosystem, sagebrush …


Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver Jan 2018

Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver

All Master's Theses

Along the Columbia River, hundreds of miles of transportation infrastructure and over sixty hydroelectric dams have been constructed. This altered a rich cultural landscape with evidence of 10,000 years of continuous occupation. Researchers have attempted to understand the impacts of anthropogenic factors on the Columbia River, focusing on the riverine environment. However, the effect of transportation and hydroelectricity developments to eolian landforms on the floodplains and adjoining slopes have not been studied. Focusing on 2,800 acres near Celilo Falls, this study 1) establishes a baseline condition of eolian landforms from 1805 to 1900; 2) conducts an air photo increment analysis …


Glacial Deposits, Vol. 43, 2018, Department Of Geography, Geology, And The Environment Jan 2018

Glacial Deposits, Vol. 43, 2018, Department Of Geography, Geology, And The Environment

Glacial Deposits

Newsletter of the Department of Geography, Geology, and the Environment


Impacts Of Drainage Systems On Stormwater Hydrology: Rocky Branch Watershed, Columbia, South Carolina, Logan Ress Jan 2018

Impacts Of Drainage Systems On Stormwater Hydrology: Rocky Branch Watershed, Columbia, South Carolina, Logan Ress

Theses and Dissertations

The effects of urbanization and associated land use changes, specifically increases in impervious surfaces, have long been the focal point of urban hydrologic research. However, studies and calculations that consider impervious surfaces alone do not encompass all factors that influence urban hydrologic response. Artificial structures such as storm sewer (SS) systems and road networks increase rates of stormwater conveyance, yet these artificial networks are rarely considered in computations of drainage densities and associated hydrologic alterations. This study examines several hydrologically relevant descriptors that can be used to better understand the impact of urbanization on small watersheds. Rainfall and stormflow data …


The Role Of Channel Fens In Permafrost Degradation Induced Changes In Peatland Discharge At Scotty Creek, Nt, Lindsay Elena Stone Jan 2018

The Role Of Channel Fens In Permafrost Degradation Induced Changes In Peatland Discharge At Scotty Creek, Nt, Lindsay Elena Stone

Theses and Dissertations (Comprehensive)

Permafrost degradation in the peat-rich southern fringe of the discontinuous permafrost zone is producing substantial changes to land cover with concomitant expansion of permafrost-free wetlands (bogs and fens) and shrinkage of forest supported by permafrost peat plateaus. Predicting discharge from headwater basins in this region depends on understanding and numerically representing the interactions between storage and discharge within and between the major land cover types, and how these interactions are changing. To better understand the implications of land cover change on wetland discharge, the hydrological behaviour of a channel fen in the headwaters of Scotty Creek, Northwest Territories, Canada, dominated …


Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes Jan 2018

Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes

Theses and Dissertations--Plant and Soil Sciences

Irrigation needs to be applied to soils in relatively humid regions such as western Kentucky to supply water for crop uptake to optimize and stabilize yields. Characterization of soil and crop variability at the field scale is needed to apply site specific management and to optimize water application. The objective of this work is to propose a characterization and modeling of soil and crop processes to improve irrigation management. Through an analysis of spatial and temporal behavior of soil and crop variables the variability in the field was identified. Integrative analysis of soil, crop, proximal and remote sensing data was …


Effects Of Increasing Deciduous Shrub Litter On Ecosystem Functioning In Alpine Tundra, Alejandro Emmanuel Benhumea Jan 2018

Effects Of Increasing Deciduous Shrub Litter On Ecosystem Functioning In Alpine Tundra, Alejandro Emmanuel Benhumea

Open Access Theses & Dissertations

Rising temperatures due to global warming have resulted in rapid environmental changes in northern environments, resulting in an increase in deciduous shrub growth which has the potential to alter soil ecosystem properties and processes. In order to address some potential mechanisms by which shrubs alter ecosystem properties and processes, we designed an experiment which separated the effects of physical shrub presence and the effects of litter quantity in a fully factorial experiment on a north facing alpine plateau in the southwest Yukon, Canada. Specifically, we asked the following questions: What are effects of shrub litter, independent of shrub presence, on …


Geometry, Timing, And Kinematics Of Neogene Extensional And Transtensional Structures Of Southern Death Valley: Implications For Regional Reconstructions And A Corrective Method For Rigid Body Rotations, Zachariah Fleming Jan 2018

Geometry, Timing, And Kinematics Of Neogene Extensional And Transtensional Structures Of Southern Death Valley: Implications For Regional Reconstructions And A Corrective Method For Rigid Body Rotations, Zachariah Fleming

Open Access Theses & Dissertations

Chapter 1:Advancements in computing capabilities over the last decade have allowed for the routine creation of Structure from Motion-Multiview Stereo (SfM-MVS) terrain models that can serve as base for high resolution geologic mapping. Outcrops models developed from these systems are high-resolution, photo-realistic 3D base providing unprecedented capability for geometric analysis. Yet, before this technology becomes a mainstay of field geology, the potential errors associated with it must be well understood. Here, we compare orientation measurements from multi-point analyses on the SfM-MVS point clouds to those taken in the field with the objective of resolving the geometry of complex folds within …


The Performance Of 2d And 3d Tsunami Evacuation Maps: A Case Study For Seaside, Oregon, Aaron M. Taveras Jan 2018

The Performance Of 2d And 3d Tsunami Evacuation Maps: A Case Study For Seaside, Oregon, Aaron M. Taveras

Cal Poly Humboldt theses and projects

Tsunami evacuation maps are intended to inform the public about the geographic extent of the hazard and where to evacuate, but these maps can be difficult to interpret for people unfamiliar with cartographic semiology. This study focuses on the performance of tsunami evacuation maps and how the tsunami hazard is represented cartographically, as at-risk communities must be able to act quickly, and effectively understand tsunami maps to remain aware of the hazard and adequately evacuate. This study investigated the use of static three-dimensional (3D) perspective maps and travel time to safety representation (shown using point markers and choropleth symbology), as …


Driving Factors On Runoff Change In The North Semiarid Rapidly Urbanization Watershed, Yong Bai, Rui-Zhong Gao, Xi-Xi Wang, Wei-Na Wang Jan 2018

Driving Factors On Runoff Change In The North Semiarid Rapidly Urbanization Watershed, Yong Bai, Rui-Zhong Gao, Xi-Xi Wang, Wei-Na Wang

Civil & Environmental Engineering Faculty Publications

The hydrological process of a watershed influences a lot on the local socioeconomic development. The analysis of runoff change caused by the rapid urbanization on the watershed is of important significance in the management and protection of the local water resource. In this study, based on the land use information from remotely sensed images, the hydrometeorological observation data and the social economy data from 1997 to 2015, the relationship between the influencing factors and the runoff trend in Wulanmulun River watershed was analyzed at different time scale using the improved Mann-Kendall Test and PCA (principal component analysis) method. The results …


Spatial And Temporal Variability Of The Snow Environment In The Western Canadian Arctic, Philip Mann Jan 2018

Spatial And Temporal Variability Of The Snow Environment In The Western Canadian Arctic, Philip Mann

Theses and Dissertations (Comprehensive)

Snow cover in the Western Canadian Arctic is a significant input to the hydrological mass balance, it produces shelter and habitat for animals and humans, and supports interactions with vegetation and climate. The Arctic-tundra snow cover is greatly impacted by wind erosion, redistribution and deposition of snow during high wind events over the winter months. As a result, the end of winter snow cover is characterised by significant small-scale (on the order of a few meters) spatial variations in snow cover depth, density, and thus snow water equivalent (SWE), and runoff. Future climate related changes to snow cover depth and …


The Effects Of Fire On Snow Accumulation, Snowmelt And Ground Thaw On A Peat Plateau In Subarctic Canada, Elyse Mathieu Jan 2018

The Effects Of Fire On Snow Accumulation, Snowmelt And Ground Thaw On A Peat Plateau In Subarctic Canada, Elyse Mathieu

Theses and Dissertations (Comprehensive)

During the past century, the highest rates of warming have occurred at latitudes above 60oN, where air temperatures have risen at twice the rate of other regions. In northwestern Canada, this warming has coincided with an increase in the frequency, size and severity of wildfires. The influence of such fires on the trajectory of on-going permafrost thaw is not well understood. As a consequence, the combined impacts of climate warming induced permafrost thaw and possible feedbacks arising from wildfires cannot be properly assessed. This study examines the impact of a 2.7 ha low-severity wildfire (July 2014) on water …


Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul Jan 2018

Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul

Theses and Dissertations (Comprehensive)

Accelerated climate warming in northern regions is causing permafrost degradation, leading to the reduction of the areal extent of permafrost. Permafrost is the foundation for many northern ecosystems and communities, so its thaw can have important ecological and societal consequences. Thaw of ice-rich permafrost can cause subsidence of the ground surface proportional to excess ice content. Terrain settlement can cause ponding or damage to infrastructure. Following a surface disturbance that removes much of the vegetation cover, a shift in the ground thermal regime can cause an increase in active layer thickness and rapid thaw of the top portion of permafrost. …


Terrestrial Lidar Raw Dataset For: Stemflow Dynamics In Relation To Individual Tree Canopy Structure, Neighborhood Conditions, And Meteorological Factors, Sandra A. Yankine, John T. Van Stan Ii, Jean-Francois Cote, Anke Hildebrandt, Dylan C. Mesta, Gustavo O. Maldonado, Jan Friesen Jan 2018

Terrestrial Lidar Raw Dataset For: Stemflow Dynamics In Relation To Individual Tree Canopy Structure, Neighborhood Conditions, And Meteorological Factors, Sandra A. Yankine, John T. Van Stan Ii, Jean-Francois Cote, Anke Hildebrandt, Dylan C. Mesta, Gustavo O. Maldonado, Jan Friesen

Datasets

These are raw 3-D (x,y,z) point files of a forest plot. Scans were collected at Herty Pines in Statesboro, Georgia, USA. Scans were collected using a Leica ScanStation C-10. Files were co-registered using Leica Cyclone II. Although file extension is ".pts" these are in ASCII format.


Temporal Changes In Submarine Groundwater Discharge In A Georgia Salt Marsh, Tanner C. Avery, Jacque L. Kelly Jan 2018

Temporal Changes In Submarine Groundwater Discharge In A Georgia Salt Marsh, Tanner C. Avery, Jacque L. Kelly

Earth, Environment & Sustainability: Faculty Presentations (1988-2022)

No abstract provided.


Imaging The Subsurface In Eastern Part Of Lake Chesterfield Using A Combination Of Geophysical Tools, Jiawei Li Jan 2018

Imaging The Subsurface In Eastern Part Of Lake Chesterfield Using A Combination Of Geophysical Tools, Jiawei Li

Masters Theses

"The Lake Chesterfield North Dam in Wildwood city, Missouri has been leaking, more or less continuously since the dam was constructed in 1986 despite mitigation efforts in 1988, 1994, 1995, 2004, and 2005. Neither the grouting efforts in 1988, 1994, 1995, 2004 or 2005, nor the placement and rehabilitation of an impervious clay liner in 2005 has solved the problem. Indeed, in June of 2017, the water level in Lake Chesterfield dropped at an alarmingly rapid rate.

Prior to authorizing additional mitigation work, the Lake Chesterfield Home Owners Association (LCHOA) decided to acquire geophysical data across the dry lake bed. …


Hydrogeology And Water Management In The Arkwright Underground Coal Mine, Pittsburgh Seam, Northern West Virginia, Bryant D. Mountjoy Jan 2018

Hydrogeology And Water Management In The Arkwright Underground Coal Mine, Pittsburgh Seam, Northern West Virginia, Bryant D. Mountjoy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Arkwright #1 is a closed underground mine in the Pittsburgh coal seam near Morgantown, West Virginia USA. Arkwright shares perimeter boundaries/barriers with three other closed Pittsburgh seam mines (Osage #3, Jordan #93, Federal #1) and is partially overlain by flooded Sewickley seam mines, 25 m above it. This mine is significant primarily because it manages and treats water diverted from nearly 20 other closed mines over a 600 square kilometer area. This study examines water levels, pump records, and mine maps to describe the hydrogeology of Arkwright Mine. After closure in 1995, Arkwright and the adjacent northern Osage mines began …


Population Dynamics And Water Resource Consumption In Spokane, Wa, Daniel Jesus Castillo Jan 2018

Population Dynamics And Water Resource Consumption In Spokane, Wa, Daniel Jesus Castillo

EWU Masters Thesis Collection

No abstract provided.


Spatial And Temporal Analysis Of Surface Water Quality In Relation To Marcellus Shale Gas Development In The Northern Panhandle Of West Virginia, Rachel Yesenchak Jan 2018

Spatial And Temporal Analysis Of Surface Water Quality In Relation To Marcellus Shale Gas Development In The Northern Panhandle Of West Virginia, Rachel Yesenchak

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pre-existing water chemistry data available from the West Virginia Department of Environmental Protection were used to examine temporal changes in surface water quality related to the onset of Marcellus Shale gas drilling activity in the state of West Virginia. Drilling is concentrated in the northwestern portion of the state. Watersheds were delineated for twelve discrete stream sampling locations in the Upper Ohio-Wheeling HUC-8 sub-basin, where shale gas drilling is prevalent. Kruskal-Wallis tests were deployed to compare pre- and post-drilling concentrations of conductivity, chloride, and total suspended solids for each location. Increased concentrations of these parameters are associated with surface water …


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 Jan 2018

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, …


Recent Ecological Change In Ancient Lakes, Stephanie E. Hampton, Suzanne Mcgowan, Ted Ozersky, Salvatore G. P. Virdis, Tuong Thuy Vu, Trisha L. Spanbauer, Benjamin M. Kraemer, George Swann, Anson W. Mackay, Stephen M. Powers, Michael F. Meyer, Stephanie G. Labou, Catherine M. O'Reilly, Morgan Dicarlo, Aaron W. E. Galloway, Sherilyn C. Fritz Jan 2018

Recent Ecological Change In Ancient Lakes, Stephanie E. Hampton, Suzanne Mcgowan, Ted Ozersky, Salvatore G. P. Virdis, Tuong Thuy Vu, Trisha L. Spanbauer, Benjamin M. Kraemer, George Swann, Anson W. Mackay, Stephen M. Powers, Michael F. Meyer, Stephanie G. Labou, Catherine M. O'Reilly, Morgan Dicarlo, Aaron W. E. Galloway, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

Ancient lakes are among the best archivists of past environmental change, having experienced more than one full glacial cycle, a wide range of climatic conditions, tectonic events, and long association with human settlements. These lakes not only record long histories of environmental variation and human activity in their sediments, but also harbor very high levels of biodiversity and endemism. Yet, ancient lakes are faced with a familiar suite of anthropogenic threats, which may degrade the unusual properties that make them especially valuable to science and society. In all ancient lakes for which data exist, significant warming of surface waters has …


Evaluating Soil Moisture–Precipitation Interactions Using Remote Sensing: A Sensitivity Analysis, Trent W. Ford, Steven M. Quiring, Balbhadra Thakur, Rohit Jogineedi, Adam Houston, Shanshui Yuan, Ajay Kalra, Noah Lock Jan 2018

Evaluating Soil Moisture–Precipitation Interactions Using Remote Sensing: A Sensitivity Analysis, Trent W. Ford, Steven M. Quiring, Balbhadra Thakur, Rohit Jogineedi, Adam Houston, Shanshui Yuan, Ajay Kalra, Noah Lock

Department of Earth and Atmospheric Sciences: Faculty Publications

The complex interactions between soil moisture and precipitation are difficult to observe, and consequently there is a lack of consensus as to the sign, strength, and location of these interactions. Inconsistency between soil moisture–precipitation interaction studies can be attributed to a multitude of factors, including the difficulty of demonstrating causal relationships, dataset differences, and precipitation autocorrelation. The purpose of this study is to explore these potential confounding factors and determine which are most important for consideration when assessing statistical coupling between soil moisture and precipitation. Soil moisture is assessed via three remote sensing datasets: theAdvancedMicrowave Scanning Radiometer for EarthObserving System, …


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 Jan 2018

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 …


Environmental Governance And Climate Change Adaptation In The Okavango Delta, Botswana, Jamie Shinn Jan 2018

Environmental Governance And Climate Change Adaptation In The Okavango Delta, Botswana, Jamie Shinn

Faculty & Staff Scholarship

Increased environmental variability as a result of climate change will continue to intensify in coming decades, with particularly acute consequences for those living in already marginal conditions. The impacts of these biophysical changes require new approaches to environmental governance to facilitate successful forms of climate change adaptation for individuals and communities in changing social-ecological systems.


Reducing Uncertainties In Applying Remotely Sensed Land Use And Land Cover Maps In Land-Atmosphere Interaction: Identifying Change In Space And Time, Yaqian He, Timothy A. Warner, Brenden E. Mcneil, Eungul Lee Jan 2018

Reducing Uncertainties In Applying Remotely Sensed Land Use And Land Cover Maps In Land-Atmosphere Interaction: Identifying Change In Space And Time, Yaqian He, Timothy A. Warner, Brenden E. Mcneil, Eungul Lee

Faculty & Staff Scholarship

Land use and land cover (LULC) data are a central component of most land-atmosphere interaction studies, but there are two common and highly problematic scale mismatches between LULC and climate data. First, in the spatial domain, researchers rarely consider the impact of scaling up fine-scale LULC data to match coarse-scale climate datasets. Second, in the temporal domain, climate data typically have sub-daily, daily, monthly, or annual resolution, but LULC datasets often have much coarser (e.g., decadal) resolution. We first explored the effect of three spatial scaling methods on correlations among LULC data and a land surface climatic variable, latent heat …


Past And Future Drought In Mongolia, Amy Hessl, Kevin J. Anchukaitis, Casey Jelsema, Benjamin Cook, Oyunsanaa Byambasuren, Caroline Leland, Baatarbileg Nachin, Neil Pederson, Hanqin Tian, Laia Andreu Hayles Jan 2018

Past And Future Drought In Mongolia, Amy Hessl, Kevin J. Anchukaitis, Casey Jelsema, Benjamin Cook, Oyunsanaa Byambasuren, Caroline Leland, Baatarbileg Nachin, Neil Pederson, Hanqin Tian, Laia Andreu Hayles

Faculty & Staff Scholarship

The severity of recent droughts in semiarid regions is increasingly attributed to anthropogenic climate change, but it is unclear whether these moisture anomalies exceed those of the past and how past variability compares to future projections. On the Mongolian Plateau, a recent decade-long drought that exceeded the variability in the instrumental record was associated with economic, social, and environmental change. We evaluate this drought using an annual reconstruction of the Palmer Drought Severity Index (PDSI) spanning the last 2060 years in concert with simulations of past and future drought through the year 2100 CE.We show that although the most recent …


Improved Kerogen Models For Determining Thermal Maturity And Hydrocarbon Potential Of Shale, Vikas Agrawal, Shikha Sharma Jan 2018

Improved Kerogen Models For Determining Thermal Maturity And Hydrocarbon Potential Of Shale, Vikas Agrawal, Shikha Sharma

Faculty & Staff Scholarship

Kerogen is the insoluble component of organic-rich shales that controls the type and amount of

hydrocarbons generated in conventional and unconventional reservoirs. Significant progress has

recently been made in developing structural models of kerogen. However, there is still a large gap in understanding the evolution of the molecular components of kerogen with thermal maturation and their hydrocarbon (HC) generative potential. Here, we determine the variations in different molecular fragments of kerogen from a Marcellus Shale maturity series (with VRo ranging from 0.8 to 3) using quantitative 13C MultiCP/MAS NMR and MultiCP NMR/DD (dipolar dephasing). These molecular variations provide insight into …


Risk Assessment And Mapping Of Hand, Foot, And Mouth Disease At The County Level In Mainland China Using Spatiotemporal Zero-Inflated Bayesian Hierarchical Models, Chao Song, Yaqian He, Yanchen Bo, Jinfeng Wang, Zhoupeng Ren, Huibin Yang Jan 2018

Risk Assessment And Mapping Of Hand, Foot, And Mouth Disease At The County Level In Mainland China Using Spatiotemporal Zero-Inflated Bayesian Hierarchical Models, Chao Song, Yaqian He, Yanchen Bo, Jinfeng Wang, Zhoupeng Ren, Huibin Yang

Faculty & Staff Scholarship

Hand, foot, and mouth disease (HFMD) is a worldwide infectious disease, prominent in China. China’s HFMD data are sparse with a large number of observed zeros across locations and over time. However, no previous studies have considered such a zero-inflated problem on HFMD’s spatiotemporal risk analysis and mapping, not to mention for the entire Mainland China at county level. Monthly county-level HFMD cases data combined with related climate and socioeconomic variables were collected. We developed four models, including spatiotemporal Poisson, negative binomial, zero-inflated Poisson (ZIP), and zero-inflated negative binomial (ZINB) models under the Bayesian hierarchical modeling framework to explore disease …