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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 2018 West Virginia University

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 2018 West Virginia University

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 …


On The Spatial Modelling Of Mixed And Constrained Geospatial Data, Hassan Talebi 2018 Edith Cowan University

On The Spatial Modelling Of Mixed And Constrained Geospatial Data, Hassan Talebi

Theses: Doctorates and Masters

Spatial uncertainty modelling and prediction of a set of regionalized dependent variables from various sample spaces (e.g. continuous and categorical) is a common challenge for geoscience modellers and many geoscience applications such as evaluation of mineral resources, characterization of oil reservoirs or hydrology of groundwater. To consider the complex statistical and spatial relationships, categorical data such as rock types, soil types, alteration units, and continental crustal blocks should be modelled jointly with other continuous attributes (e.g. porosity, permeability, seismic velocity, mineral and geochemical compositions or pollutant concentration). These multivariate geospatial data normally have complex statistical and spatial relationships which should …


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

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 …


Spatial And Temporal Characterization Of The Petrified Springs Fault, Central Walker Lane, Nevada: Documenting Middle Miocene Dextral Slip, Andrew Hoxey 2018 Central Washington University

Spatial And Temporal Characterization Of The Petrified Springs Fault, Central Walker Lane, Nevada: Documenting Middle Miocene Dextral Slip, Andrew Hoxey

All Master's Theses

The Central Walker Lane, NV is an active dextral shear zone superimposed on the western boundary of the Basin and Range extensional province. Approximately 25% of dextral shear along the Pacific-North American plate boundary accommodated in the Walker Lane, a NW-striking, intracontinental dextral fault system in eastern California- western Nevada. In the Central Walker Lane, shear is accommodated on five major NW- striking faults, one of which is the Petrified Springs fault, with poorly constrained slip magnitudes, slip rates, and initiation ages. We completed new detailed geologic mapping, combined with structural studies, and 40Ar/39Ar geochronology document offset …


Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach 2018 Central Washington University

Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach

All Master's Theses

The nearly continuous volcanic eruption record at Mt. Etna dating back approximately 700 years provides an excellent opportunity to investigate the geochemical evolution of a highly active volcano. Of particular interest is elucidating the cause of a selective enrichment in alkali elements (K, Rb, Cs) and 87Sr/86Sr. This alkali enrichment trend, which began in the 17th century and accelerated after 1971, was accompanied by an increase in the volume, frequency, and explosivity of eruptions. To explain this enrichment, two major arguments are invoked: (1) crustal contributions (e.g., assimilation of the sedimentary basement), and (2) changes in …


2017 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, H. Reiners-Hild 2017 University of Nebraska at Lincoln

2017 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, H. Reiners-Hild

Conservation and Survey Division: Faculty and Staff Publications

Twenty participants completed the 2017 Water Leaders Academy bringing the total number of graduates to 101 since the inception of the program in 2011. Assessment of participants’ transformational leadership skills, champion of innovation skills, water knowledge and engagement, civic capacity, and entrepreneurial leadership behaviors showed a significant increase over the course of the year, from both participants’ and their raters’ perspectives. Feedback from participants was highly positive and constructive. Participant concerns were addressed, and only minor changes are planned for the 2018 Academy curriculum. Results of the program assessment indicate that the curriculum is meeting Academy objectives. Most importantly, Alumni …


Hydrodynamic Controls On The Morphodynamic Evolution Of Subaqueous Landforms, Timothy L. Nelson 2017 LSU New Orleans

Hydrodynamic Controls On The Morphodynamic Evolution Of Subaqueous Landforms, Timothy L. Nelson

LSU New Orleans Theses and Dissertations

The southern Chandeleur Islands are an ideal setting to study shoal evolution given their history of submergence and re-emergence. Here, numerical models shed light on the attendant processes contributing to shoal recovery/reemergence following a destructive storm event. Simulations of a synthetic winter storm along a cross-shore profile using Xbeach shows that convergence of wave-induced sediment transport associated with repeated passage of cold-fronts initiates aggradation, but does not lead to reemergence. A Delft3d model of the entire island chain shows that as these landforms aggrade alongshore processes driven by incident wave refraction on the shoal platform, backbarrier circulation and resulting transport …


Characterizing Basement Structures To Evaluate Their Influence On Overlaying Sedimentary Layers: Case Study Of Three Fields In The Central Kansas Uplift, Muhammad S. Karim 2017 Fort Hays State University

Characterizing Basement Structures To Evaluate Their Influence On Overlaying Sedimentary Layers: Case Study Of Three Fields In The Central Kansas Uplift, Muhammad S. Karim

Master's Theses or Doctor of Nursing Practice

Potential field and well log data were used to investigate basement features and the overlaying sedimentary layers across four counties in the Central Kansas Uplift. The objective of this study was to (1) investigate and determine the orientation of basement structures/features, (2) estimate the depth to basement, and (3) examine the influence (if any) and relationship between the basement features and the overlaying sedimentary deposits of three oil fields in the study area. Aeromagnetic data was used to interpret and map basement features by applying derivative filters. Well log data was used to pick formation top values and create contour …


Geology Of The Northern Alto Relex Area, Big Bend National Park, Brewster County, Texas, Robert Schoen 2017 Stephen F. Austin State University

Geology Of The Northern Alto Relex Area, Big Bend National Park, Brewster County, Texas, Robert Schoen

Electronic Theses and Dissertations

Detailed, 1:12,000-scale geologic field mapping was conducted around Alto Relex in the northern Sierra Del Carmen Mountains in Big Bend National Park. Alto Relex is a prominent, near vertical, ~1000 foot-high fault-line scarp. Cretaceous rocks in the area were folded and faulted by Laramide compression, intruded by Tertiary sills and overprinted by high-angle normal faults from Basin and Range extension. During the Laramide Orogeny and Basin and Range extension, the underlying basement shear zone called, the Texas Lineament, was reactivated creating a transpressional and transtensional regimes. The general geology of this area was outlined by Moustafa (1988) working primarily from …


Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz 2017 Stephen F. Austin State University

Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz

Electronic Theses and Dissertations

Preliminary investigation of the Bullard Peak metamorphic series (BPMS) in the northwestern Wind Mountain quadrangle within the Burro Mountains of southwestern New Mexico suggests a possible previously unidentified shear zone, prompting detailed (1:12,000) geologic mapping and collection of structural data. The study area has a complex tectonic history, including 1) ~1.65 Ga metamorphism during accretion of the Mazatzal terrane to Laurentia’s southern margin; 2) ~1.4 Ga intrusion of Granite and Rhyolite Province granitoids; 3) significant uplift during the formation of the Ancestral Rockies (~300 Ma) and the Rocky Mountains (~70-50 Ma); and 4) inversion tectonics with reactivation of compressional faults …


Enhanced Recent Local Moisture Recycling On The Northwestern Tibetan Plateau Deduced From Ice Core Deuterium Excess Records, Wenling An, Shugui Hou, Qiong Zhang, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu 2017 Nanjing University

Enhanced Recent Local Moisture Recycling On The Northwestern Tibetan Plateau Deduced From Ice Core Deuterium Excess Records, Wenling An, Shugui Hou, Qiong Zhang, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu

Department of Earth, Environment and Sustainability Faculty Publications

Local moisture recycling plays an essential role in maintaining an active hydrological cycle of the Tibetan Plateau (TP). Previous studies were largely limited to the seasonal time scale due to short and sparse observations, especially for the northwestern TP. In this study, we used a two‐component mixing model to estimate local moisture recycling over the past decades from the deuterium excess records of two ice cores (i.e., Chongce and Zangser Kangri) from the northwestern TP. The results show that on average almost half of the precipitation on the northwestern TP is provided by local moisture recycling. In addition, the local …


Using Foraminifera In Stemseas Site 1 To Understand The Recent Paleoceanographic And Paleoclimatic History Of Tanner Basin, California Borderland, Michael Stanley Stone 2017 James Madison University

Using Foraminifera In Stemseas Site 1 To Understand The Recent Paleoceanographic And Paleoclimatic History Of Tanner Basin, California Borderland, Michael Stanley Stone

Senior Honors Projects, 2010-2019

In May of 2016, the STEMSEAS Educational Transit cruise OC1605-tranA collected the STEMSEAS Site 1 core from the Tanner Basin in the California Borderland. This research serves as the first formal survey of the foraminifera preserved within that core. The purpose of this research is to use foraminifera preserved within that core to understand the recent depositional and paleoenvironmental conditions at Site 1, and to place that information into a regional paleoceanographic and paleoclimatic context. In pursuing this purpose, this research aims to answer three questions: 1) Can biostratigraphic markers in the foraminiferal assemblages in STEMSEAS Site 1 core be …


Outer Space: A Steam Voyage, Jancy McPhee 2017 SciArt Exchange

Outer Space: A Steam Voyage, Jancy Mcphee

The Transdisciplinary STEAM+ Journal

SciArt Exchange offers multi-disciplinary art contests, artwork events, consulting, training and community resources to support science and technology education, collaboration, and innovation. Using a science-integrated- with-art approach, SciArt Exchange supports, prepares, and convenes people of all ages, backgrounds and affiliations to discuss and potentially solve space, science, and technology challenges. This field note shares the Humans in Space Art Program and the Project Mars Competition.


Effect Of An 860-M Thick, Cold, Freshwater Aquifer On Geothermal Potential Along The Axis Of The Eastern Snake River Plain, Idaho, Thomas E. Lachmar, Thomas G. Freeman, Christopher J. Sant, Jeffrey R. Walker, Joseph F. Batir, John W. Shervais, James P. Evans, Dennis L. Nielson, David D. Blackwell 2017 Utah State University

Effect Of An 860-M Thick, Cold, Freshwater Aquifer On Geothermal Potential Along The Axis Of The Eastern Snake River Plain, Idaho, Thomas E. Lachmar, Thomas G. Freeman, Christopher J. Sant, Jeffrey R. Walker, Joseph F. Batir, John W. Shervais, James P. Evans, Dennis L. Nielson, David D. Blackwell

Geosciences Faculty Publications

A 1912-m exploration corehole was drilled along the axis of the eastern Snake River Plain, Idaho. Two temperature logs run on the corehole display an obvious inflection point at about 960 m. Such behavior is indicative of downward fluid flow in the wellbore. The geothermal gradient above 935 m is 4.5 °C/km, while the gradient is 72–75 °C/km from 980 to 1440 m. Projecting the higher gradients upward to where they intersect the lower gradient on the temperature logs places the bottom of the cold, freshwater Snake River Plain aquifer, which suppresses the geothermal gradient at this location, at least …


The Sedimentary Imprint Of Pleistocene Glacio-Eustasy: Implications For Global Correlations Of Seismic Sequences, Cecilia M. McHugh, Craig S. Fulthorpe, Koichi Hoyanagi, Peter Blum, Gregory S. Mountain, Kenneth G. Miller 2017 CUNY Queens College

The Sedimentary Imprint Of Pleistocene Glacio-Eustasy: Implications For Global Correlations Of Seismic Sequences, Cecilia M. Mchugh, Craig S. Fulthorpe, Koichi Hoyanagi, Peter Blum, Gregory S. Mountain, Kenneth G. Miller

Publications and Research

We evaluate lithofacies, chronology, and seismic sequences from the Canterbury Basin, New Zealand passive continental slope (Integrated Ocean Drilling Program [IODP] Expedition 317 Site U1352 and environs) and compare this with slope sequences from the New Jersey passive margin. Our goal is to understand continental slope sedimentation in response to glacio-eustasy and test the concepts of sequence stratigraphy. High-resolution geochemical elemental and lithostratigraphic analyses were calibrated to a chronology constructed from benthic foramininferal oxygen isotopes for the past ~1.8 m.y. We identify lithofacies successions by their unique geochemical and lithologic signature and correlate them with marine isotope stages (MIS) at …


Classification Of A Meteorite Found Near Colgate, North Dakota, Justin Germann 2017 University of North Dakota

Classification Of A Meteorite Found Near Colgate, North Dakota, Justin Germann

Undergraduate Theses and Senior Projects

In 1999 a 39 Kg stony meteorite was found near Colgate, North Dakota, during the construction of a new house. The surface of the meteorite contains many shallow regmaglypts and a weathered crust with a reddish orange color to dark brown-red, and the interior reveals a high abundance of metallic flecks. The SiO2/MgO ratio is 1.5, FeO/SiO2 ratio is 0.71, the Femetallic/FeO ratio is 0.72, the total metallic Fe is 19.8%,the average chondrule diameter is 0.3 mm, and the Fa composition is 20.27 mol%. The meteorite also has a crystalline matrix, with mostly well segregated chondrules, little igneous glass, and …


Usarray Imaging Of Continental Crust In The Conterminous United States, Xiaofei Ma, Anthony R. Lowry 2017 Utah State University

Usarray Imaging Of Continental Crust In The Conterminous United States, Xiaofei Ma, Anthony R. Lowry

Geosciences Faculty Publications

The thickness and bulk composition of continental crust provide important constraints on the evolution and dynamics of continents. Crustal mineralogy and thickness both may influence gravity anomalies, topographic elevation, and lithospheric strength, but prior to the inception of EarthScope’s USArray, seismic measurements of crustal thickness and properties useful for inferring lithology are sparse. Here we improve upon a previously published methodology for joint inversion of Bouguer gravity anomalies and seismic receiver functions by using parameter space stacking of cross correlations of modeled synthetic and observed receiver functions instead of standard H-κ amplitude stacking. The new method is applied to estimation …


Geological Framework Of The Continental Shelf Of South Carolina Winyah Bay: Paleodrainage, Transgressions And Essential Fish Habitat, Amanda Roach 2017 Coastal Carolina University

Geological Framework Of The Continental Shelf Of South Carolina Winyah Bay: Paleodrainage, Transgressions And Essential Fish Habitat, Amanda Roach

Electronic Theses and Dissertations

A regional geophysical survey of the inner continental shelf off central South Carolina was completed on a cooperative cruise between NOAA and Coastal Carolina University in July 2015. An integrated mapping suite comprised of subbottom echosounder, side scan, multibeam and split beam sonars was used to define the regional geologic framework, including paleodrainage patterns across the shelf and to identify potential fish habitat locations that will provide additional inputs to a thematic habitat mapping routine developed by NOAA. Results from the thematic mapper characterization suggest that large-scale framework elements such as paleochannel networks may play a role in determining benthic …


Re–Os Isotope Geochronology Of The Shangbao Pyrite–Flourite Deposit In Southeastern Hunan, South China: Evidence For Multiple Mineralization Events And The Role Of Crust–Mantle Interaction In Polymetallic Deposits, Cheng Cheng Huang, Hai Feng Guo, Jie Li, Qiang Wang, Chunfu Zhang, Derek Wyman, Gong Jian Tang 2017 Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Re–Os Isotope Geochronology Of The Shangbao Pyrite–Flourite Deposit In Southeastern Hunan, South China: Evidence For Multiple Mineralization Events And The Role Of Crust–Mantle Interaction In Polymetallic Deposits, Cheng Cheng Huang, Hai Feng Guo, Jie Li, Qiang Wang, Chunfu Zhang, Derek Wyman, Gong Jian Tang

Geosciences Faculty Publications

In South China, both crustal reworking and crust–mantle interaction were important geological processes during the Paleozoic and Mesozoic eras. However, the relationships between these two processes and metal mineralization are still unknown. Here we report rhenium and osmium isotopic data for pyrite grains from a pyrite deposit associated with a granite intrusion in the Shangbao area, southeastern Hunan Province (South China). Two pyrite samples, both containing many euhedral pyrite grains, were collected from the same locality, but the samples yield distinct ages. Six euhedral pyrite grains from one sample yield an isochronal age of 279 ± 12 Ma, with an …


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