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2017

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Full-Text Articles in Physical Sciences and Mathematics

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

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

Conservation and Survey Division

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 …


Evaluation Of The Community Multiscale Air Quality Model For Simulating Winter Ozone Formation In The Uinta Basin, Rebecca Matichuk, Gail Tonnesen, Deborah Luecken, Rob Gillam, Sergey L. Napelenok, Kirk R. Baker, Donna Schwede, Ben Murphy, Detlev Helmig, Seth N. Lyman, Shawn Roselle Dec 2017

Evaluation Of The Community Multiscale Air Quality Model For Simulating Winter Ozone Formation In The Uinta Basin, Rebecca Matichuk, Gail Tonnesen, Deborah Luecken, Rob Gillam, Sergey L. Napelenok, Kirk R. Baker, Donna Schwede, Ben Murphy, Detlev Helmig, Seth N. Lyman, Shawn Roselle

Bingham Research Center

The Weather Research and Forecasting (WRF) and Community Multiscale Air Quality (CMAQ) models were used to simulate a 10 day high-ozone episode observed during the 2013 Uinta Basin Winter Ozone Study (UBWOS). The baseline model had a large negative bias when compared to ozone (O3) and volatile organic compound (VOC) measurements across the basin. Contrary to other wintertime Uinta Basin studies, predicted nitrogen oxides (NOx) were typically low compared to measurements. Increases to oil and gas VOC emissions resulted in O3 predictions closer to observations, and nighttime O3 improved when reducing the deposition velocity …


Probiotic Strain Stenotrophomonas Acidaminiphila Bj1 Degrades And Reduces Chlorothalonil Toxicity To Soil Enzymes, Microbial Communities And Plant Roots, Qingming Zhang, Muhammad Saleem, Caixia Wang Dec 2017

Probiotic Strain Stenotrophomonas Acidaminiphila Bj1 Degrades And Reduces Chlorothalonil Toxicity To Soil Enzymes, Microbial Communities And Plant Roots, Qingming Zhang, Muhammad Saleem, Caixia Wang

Plant and Soil Sciences Faculty Publications

Chlorothalonil, a non-systemic and broad-spectrum fungicide, is widely used to control the pathogens of agricultural plants. Although microbial degradation of chlorothalonil is known, we know little about the colonization and degradation capacity of these microbes in the natural and semi-natural soil environments. Therefore, we studied the colonization and detoxification potential of a chlorothalonil degrading Stenotrophomonas acidaminiphila probiotic strain BJ1 in the soil under green conditions. The results from polymerase chain reaction-denaturing gradient gel electrophoresis demonstrated that probiotic strain BJ1 successfully colonized the soil by competing with the native biota. Moreover, the bacterial inoculation stimulated some members of indigenous soil microbial …


Flowstone Growth In Gournier River (Vercors, France): A Diachronic Landscape Analysis By 3d Modelling And Photo Draping, Kim Genuite, Yves Perrette, Stéphane Jaillet Dec 2017

Flowstone Growth In Gournier River (Vercors, France): A Diachronic Landscape Analysis By 3d Modelling And Photo Draping, Kim Genuite, Yves Perrette, Stéphane Jaillet

International Journal of Speleology

Calcite surface has been reported by cavers and scientists over the last decades. Here, we present a methodological work aimed at quantifying that growth. We suggest a method of draping old photographs of a part of the Gournier Cave onto a 3D model. This work relies on a collection of photographs taken by cavers. We have chosen to study a site for which the maximum number of photographs was available. The series of photographs over time makes it possible to overcome the limitation of calcite crust dating. The acquisition of the 3D model has been achieved using terrestrial LIDAR. Then, …


Hydrodynamic Controls On The Morphodynamic Evolution Of Subaqueous Landforms, Timothy L. Nelson Dec 2017

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

University of 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 …


Mitigating Non-Linearity In Full Waveform Inversion Using Scaled-Sobolev Norms, Mohammad Akbar Hosain Zuberi Dec 2017

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

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

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 …


Industrial-Age Doubling Of Snow Accumulation In The Alaska Range Linked To Tropical Ocean Warming, Dominic Winski, Erich Osterberg, David Ferris, Karl Kreutz, Cameron Wake, Seth Campbell, Robert Hawley, Samuel Roy, Sean Birkel, Douglas Introne, Michael Handley Dec 2017

Industrial-Age Doubling Of Snow Accumulation In The Alaska Range Linked To Tropical Ocean Warming, Dominic Winski, Erich Osterberg, David Ferris, Karl Kreutz, Cameron Wake, Seth Campbell, Robert Hawley, Samuel Roy, Sean Birkel, Douglas Introne, Michael Handley

Dartmouth Scholarship

Future precipitation changes in a warming climate depend regionally upon the response of natural climate modes to anthropogenic forcing. North Pacific hydroclimate is dominated by the Aleutian Low, a semi-permanent wintertime feature characterized by frequent low-pressure conditions that is influenced by tropical Pacific Ocean temperatures through the Pacific-North American (PNA) teleconnection pattern. Instrumental records show a recent increase in coastal Alaskan precipitation and Aleutian Low intensification, but are of insufficient length to accurately assess low frequency trends and forcing mechanisms. Here we present a 1200-year seasonally- to annually-resolved ice core record of snow accumulation from Mt. Hunter in the Alaska …


Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl Dec 2017

Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl

Plant and Soil Sciences Faculty Publications

Mammalian herbivores are an essential component of grassland and savanna ecosystems, and with feedbacks to the climate system. To date, the response and feedbacks of mammalian herbivores to changes in both abiotic and biotic factors are poorly quantified and not adequately represented in the current global land surface modeling framework. In this study, we coupled herbivore population dynamics in a global land model (the Dynamic Land Ecosystem Model, DLEM 3.0) to simulate populations of horses, cattle, sheep, and goats, and their responses to changes in multiple environmental factors at the site level across different continents during 1980–2010. Simulated results show …


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 Dec 2017

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

Geology 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 …


Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz Dec 2017

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 …


Geology Of The Northern Alto Relex Area, Big Bend National Park, Brewster County, Texas, Robert Schoen Dec 2017

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 …


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

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 Dec 2017

Outer Space: A Steam Voyage, Jancy Mcphee

The 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.


Cataloging Wonder: The Art And Science Of The Collection, Christine Metzger Dec 2017

Cataloging Wonder: The Art And Science Of The Collection, Christine Metzger

The STEAM Journal

The Exploring Science in the Studio National Science Foundation grant funded three initiatives at California College of the Arts, a private four-year art and design college in the San Francisco Bay Area. The grant sponsored annual Science-in-the-Studio which embedded scientists into the art and design studio curriculum, the creation of Mobile Units for Scientific Exploration (MUSE) and a new collection of science materials, equipment, and natural specimens, and a national symposium on integrating science into the art and design studio curriculum. Approximately 30 SitS classes have been offered since 2010, and the Exploring Science in the Studio symposium was convened …


Rethinking Holocene Ecological Relationships Among Caribou, Muskoxen, And Human Hunters On Banks Island, Nwt, Canada: A Stable Isotope Approach, Jordon S. Munizzi Dec 2017

Rethinking Holocene Ecological Relationships Among Caribou, Muskoxen, And Human Hunters On Banks Island, Nwt, Canada: A Stable Isotope Approach, Jordon S. Munizzi

Electronic Thesis and Dissertation Repository

This dissertation explores the ecology of caribou (Rangifer tarandus spp.) and muskoxen (Ovibos moschatus), and its relevance to human hunters on Banks Island, NWT, Canada, over the last 4000 years, primarily through the isotopic analysis of modern and archaeological faunal remains.

First, we establish baseline carbon and nitrogen isotope relationships between modern vegetation and caribou and muskox bone collagen using Bayesian mixing models. The models indicate that dwarf shrub (Salix arctica) does not contribute significantly to bone collagen isotopic compositions in either species, while sedges and yellow lichen (Cetraria tilesii) do. These findings …


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 Dec 2017

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 …


Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon Dec 2017

Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon

Electronic Theses and Dissertations

Understanding lake vulnerability with respect to eutrophication and loss of water quality is important for sustainability of aquatic ecosystems. This project aims at identifying and quantifying the effects of relevant physiochemical, climate, and watershed characteristics on lake vulnerability in order to develop management decision tools for the Maine Department of Environmental Protection (MEDEP). In a changing chemical and physical environment, using independent variables from each of these categories and then relating them to the summer lake epilimnetic phosphorus (P) concentrations allows for development of models to inform stakeholders of lake vulnerability to eutrophication problems.

We studied 24 lakes covering a …


Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung Dec 2017

Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung

McKelvey School of Engineering Theses & Dissertations

Manganese (hydr)oxide (Mn (hydr)oxide) minerals are ubiquitous in aquatic and terrestrial environments. These minerals have high surface areas and are highly sorptive and redox active. From decades of accumulated knowledge about natural redox cycling, we have found that Mn (hydr)oxides play critical roles as electron donors and acceptors in elemental geochemical cycling and biological metabolisms in nature. Thus, Mn (hydr)oxides have garnered increasing interest to understand natural systems. Considering the variety of redox reactions with Mn (hydr)oxides in nature, it is also expected that there should be diverse pathways to form Mn (hydr)oxides through abiotic and biotic processes. Previous studies …


Polarimetric Synthetic Aperture Radar (Sar) Application For Geological Mapping And Resource Exploration In The Canadian Arctic, Byung-Hun Choe Dec 2017

Polarimetric Synthetic Aperture Radar (Sar) Application For Geological Mapping And Resource Exploration In The Canadian Arctic, Byung-Hun Choe

Electronic Thesis and Dissertation Repository

The role of remote sensing in geological mapping has been rapidly growing by providing predictive maps in advance of field surveys. Remote predictive maps with broad spatial coverage have been produced for northern Canada and the Canadian Arctic which are typically very difficult to access. Multi and hyperspectral airborne and spaceborne sensors are widely used for geological mapping as spectral characteristics are able to constrain the minerals and rocks that are present in a target region. Rock surfaces in the Canadian Arctic are altered by extensive glacial activity and freeze-thaw weathering, and form different surface roughnesses depending on rock type. …


Ordovician Continental Paleogeography And Paleoenvironment For The Michigan Basin From Paleomagnetic Analysis, Michelle Macrae Dec 2017

Ordovician Continental Paleogeography And Paleoenvironment For The Michigan Basin From Paleomagnetic Analysis, Michelle Macrae

Electronic Thesis and Dissertation Repository

This study investigates the paleomagnetic record of Paleozoic rocks from two Michigan basin localities in southwestern Ontario to help close the 40 myr gap in Paleozoic paleomagnetic data. Paleomagnetic data from the Queenston (Upper Ordovician) formation consistently exhibits easily removed viscous remanence, an intermediate and a high temperature component consistent with the unblocking temperatures of magnetite and hematite respectively. Alternating-field and thermal demagnetization in 16–20 steps up to 670º C typically reveal a southeastern, shallow up direction removed from magnetite, and a southwestern, steep up direction removed from hematite. A Late Paleozoic overprint was preserved in the magnetite and a …


A Method For The Geometric Analysis Of Rugose Coral Growth Ridges As Paleoenvironmental Indicators In The Middle Devonian Hungry Hollow Member Of Widder Formation, Michigan Basin, Andrew Thomson Dec 2017

A Method For The Geometric Analysis Of Rugose Coral Growth Ridges As Paleoenvironmental Indicators In The Middle Devonian Hungry Hollow Member Of Widder Formation, Michigan Basin, Andrew Thomson

Electronic Thesis and Dissertation Repository

Skeletons of Devonian rugose corals feature submillimetre-scale growth ridges on their outer surface (epitheca) that record the successive positions of the coral polyp during longitudinal corallite growth. Specimens of rugose corals Eridophyllum and Cystiphylloides from the Hungry Hollow Member of the Middle Devonian Widder Formation were sectioned longitudinally and imaged by SEM, and image processing techniques were applied to extract a line representing the epithecal surface. Local extrema found through peak detection allowed growth ridges to be represented as simplified triangles, so that geometric measurements (area, length) could be related to coral growth and analyzed in reference to possible paleoenvironmental …


Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz Dec 2017

Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz

International Journal of Speleology

The Carajás Mineral Province has one of the largest concentrations of caves in Brazil, and its iron ore is among the country’s main exports. As a result of iron ore intense extraction, new environmental policies have been implemented. In an attempt to balance economic activity and environmental conservation, an inventory and a relevance-based classification of caves were implemented in 2008 as criteria for environmental licensing of mining ventures. This implementation motivated the present study of phosphate speleothems in Carajás’ caves developed in ferriferous rocks. The objectives of this study are to describe the phosphate minerals and their formation processes based …


The Impact Of Reduced Arctic Sea Ice Extent On Cryospheric Snowfall, Alexander Carne Dec 2017

The Impact Of Reduced Arctic Sea Ice Extent On Cryospheric Snowfall, Alexander Carne

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Satellite observations show that sea ice extent in the Arctic has been declining from 1979 through present day, reaching record minimum extents in 2007 and 2012. Reduced sea ice extent allows for greater expanses of open water to interact with the Arctic atmosphere, potentially leading to changes in the Arctic climate. The greatest declines in Arctic sea ice extent have occurred in summer and autumn. During these seasons, it is likely that the decrease in Arctic sea ice extent led to an increase in atmospheric sensible and latent heat fluxes, possibly leading to increases in Arctic temperature and moisture. Increases …


Stable Cu, Fe, And Ni Isotopic Systematics Of The Sudbury Offset Dikes And Associated Rocks, Peter Christoffersen Dec 2017

Stable Cu, Fe, And Ni Isotopic Systematics Of The Sudbury Offset Dikes And Associated Rocks, Peter Christoffersen

Electronic Thesis and Dissertation Repository

The stable isotope ratio compositions of Fe, Ni, and Cu (δ56Fe, δ60Ni, and δ65Cu) are reported for the first time in rocks from the Sudbury Igneous Complex (SIC). Massive sulfide ores, Quartz Diorite (QD), Inclusion bearing Quartz Diorite (IQD), and rocks from members of the Main Mass of the SIC were analyzed. The objective was to better understand the origin(s) and source(s) of the Offset Dikes and the associated sulfide mineralization. Based on stable isotope ratios and petrographic observations, two distinct types of sulfide mineralization hosted within the Offset Dikes are identified. Massive sulfide …


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 Dec 2017

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 Dec 2017

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 Dec 2017

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 …


Improving The Accuracy Of Cosmic-Ray Neutron Probe Estimate Of Soil Water Content Using Multiple Detectors And Remote Sensing Estimates Of Vegetation, Xiaochen Dong Dec 2017

Improving The Accuracy Of Cosmic-Ray Neutron Probe Estimate Of Soil Water Content Using Multiple Detectors And Remote Sensing Estimates Of Vegetation, Xiaochen Dong

School of Natural Resources: Dissertations, Theses, and Student Research

The recently developed Cosmic-ray Neutron Probe (CRNP) for estimating soil water content (SWC) fills a critical measurement gap between point scale methods and large scale measurements collected from remote sensing. CRNP works by measuring the change in low-energy neutron intensity over time. However, the accuracy of CRNP to measure SWC is well known to be affected by other hydrogen sources (e.g. soil organic content, atmospheric water vapor, vegetation and surface water). This study focuses on the influence of rapidly growing vegetation in agricultural fields on the accuracy of the CRNP method. Here we use data from three long-term CRNP study …


Cloudsat-Based Assessment Of Gpm Microwave Imager Snowfall Observation Capabilities, Giulia Panegrossi, Jean-François Rysman, Daniele Casella, Anna Cinzia Marra, Mark Kulie Dec 2017

Cloudsat-Based Assessment Of Gpm Microwave Imager Snowfall Observation Capabilities, Giulia Panegrossi, Jean-François Rysman, Daniele Casella, Anna Cinzia Marra, Mark Kulie

Department of Geological and Mining Engineering and Sciences Publications

The sensitivity of Global Precipitation Measurement (GPM) Microwave Imager (GMI) high-frequency channels to snowfall at higher latitudes (around 60N/S) is investigated using coincident CloudSat observations. The 166 GHz channel is highlighted throughout the study due to its ice scattering sensitivity and polarization information. The analysis of three case studies evidences the important combined role of total precipitable water (TPW), supercooled cloud water,and background surface composition on the brightness temperature (TB) behavior for different snow-producing clouds. A regression tree statistical analysis applied to the entire GMI-CloudSat snowfall dataset indicates which variables influence the 166 GHz polarization difference (166∆TB)and its …