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Analysis Of Small Faults In A Sandstone Reservoir Analog, San Rafael Desert: Implications For Fluid Flow At The Reservoir-Scale, Leslie Noël Clayton 2019 Utah State University

Analysis Of Small Faults In A Sandstone Reservoir Analog, San Rafael Desert: Implications For Fluid Flow At The Reservoir-Scale, Leslie Noël Clayton

All Graduate Theses and Dissertations

We examined small-displacement faults in the Jurassic Entrada Sandstone adjacent to the Iron Wash Fault, central Utah east of the San Rafael Swell, in order to describe the nature and timing of past fluid movement and deformation in the Entrada Sandstone. Using field studies, microscopy, and X-ray diffraction analysis, we identified mineralized fractures and cementation features in association with deformation bands and fractures at the interface of the Earthy and Slick Rock Members of the Entrada Sandstone.

Where the faults cross the Earthy-Slick Rock Member interface, deformation band faults in the Slick Rock Member become opening-mode fractures in the Earthy ...


Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed 2019 University of Tennessee

Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed

University of Tennessee Honors Thesis Projects

No abstract provided.


Metadata And Minerals : A Library – Museum Pilot Project, Christine Baker 2019 Colorado School of Mines

Metadata And Minerals : A Library – Museum Pilot Project, Christine Baker

Digital Initiatives Symposium

The Arthur Lakes Library and the Geology Museum at Colorado School of Mines (Mines) worked together to explore ways to promote the Museum’s unique collections. A task force formed to conduct a pilot project that involved creating digital access, via Mines Institutional Repository, to a set of the Museum’s mineral specimens from Creede Mining District. The Metadata Librarian collaborated with the Museum Collections Manager throughout this process to establish metadata requirements and workflows. This presentation explains how the pilot project came about and describes the preparation, metadata and workflow development, as well as the collaborative experience and evolution ...


Using Principle Component Analysis To Analyze Tertiary And Quaternary Spectral Mixtures, David Burnett 2019 Olivet Nazarene University

Using Principle Component Analysis To Analyze Tertiary And Quaternary Spectral Mixtures, David Burnett

Scholar Week 2016 - present

CRISM images from Mars are expected to contain carbonates such as magnesite. Prior research has been successfully able to determine the approximate percent composition of phyllosilicates in binary lab mixtures using Principle Component Analysis (PCA). In order to expand this model to work on CRISM images, one of preliminary steps is allowing the algorithm to work on mixtures with more than two components, which was the primary purpose of this research.


Measurements Of Geomagnetic Declination (1685-1910) Using Land Surveys, Lidar, And Stone Walls, John W. Delano PhD 2019 University at Albany, State University of New York

Measurements Of Geomagnetic Declination (1685-1910) Using Land Surveys, Lidar, And Stone Walls, John W. Delano Phd

Atmospheric and Environmental Science Faculty Scholarship

Nearly 1200 kilometers of boundaries surveyed in 1685-1910, upon which stone walls were subsequently built, were measured using high-resolution LiDAR (Light Detection and Ranging) in the northeastern United States (New Hampshire and New York). The geomagnetic declinations at the time of the original land surveys of those stone wall-defined boundaries have been determined and compared with (i) current geophysical models (i.e., gufm1, IGRF12; United States Historical Declinations-USHD), and (ii) measured declinations (Bauer, 1902). With the exception of lower declinations (i.e., 1.5° eastward) in 1775-1810, the results of this study are in good agreement with gufm1 and IGRF12 ...


Spatiotemporal Variability Of Benthic Silica Fluxes In The Ngom Shelf, Byron Ebner 2019 Louisiana State University

Spatiotemporal Variability Of Benthic Silica Fluxes In The Ngom Shelf, Byron Ebner

LSU Master's Theses

Dissolved silica (DSi), plays an important role in regulating primary productivity of silicifying organisms, such as diatoms which precipitate hard parts composed of biogenic silica (bSi) in coastal and shelf ecosystems fed by major rivers. In the Northern Gulf of Mexico (NGOM), loading of nitrogen and phosphorous have increased compared to a decline in DSi in the Mississippi River. Continued decreasing in DSi loading could lead to limited diatom growth and production or shifts in community composition, therefore, it is important understand the role of benthic fluxes in providing silica to the overlying water column as there are few regional ...


Full Issue 48(1), 2019 University of South Florida

Full Issue 48(1)

International Journal of Speleology

No abstract provided.


Table Of Contents, 2019 University of South Florida

Table Of Contents

International Journal of Speleology

No abstract provided.


Guano-Related Phosphate-Rich Minerals In European Caves, Philippe Audra, Jo De Waele, Ilham Bentaleb, Alica Chroňáková, Václav Krištůfek, Ilenia M. D'Angeli, Cristina Carbone, Giuliana Madonia, Marco Vattano, Giovanna Scopelliti, Didier Cailhol, Nathalie Vanara, Marjan Temovski, Jean-Yves Bigot, Jean-Claude Nobécourt, Ermanno Galli, Fernando Rull, Aurelio Sanz-Arranz 2019 University of Nice Sophia-Antipolis

Guano-Related Phosphate-Rich Minerals In European Caves, Philippe Audra, Jo De Waele, Ilham Bentaleb, Alica Chroňáková, Václav Krištůfek, Ilenia M. D'Angeli, Cristina Carbone, Giuliana Madonia, Marco Vattano, Giovanna Scopelliti, Didier Cailhol, Nathalie Vanara, Marjan Temovski, Jean-Yves Bigot, Jean-Claude Nobécourt, Ermanno Galli, Fernando Rull, Aurelio Sanz-Arranz

International Journal of Speleology

Guano is a typical deposit found in caves derived from the excretions of bats and in minor cases of birds. These organic deposits decompose and form a series of acid fluids and gases that can interact with the minerals, sediments, and rocks present in the cave. Over sixty phosphates are known and described from caves, but guano decay also often leads to the formation of nitrates and sulfates. In this study twenty-two European caves were investigated for their guano-related secondary minerals. Using various analytical techniques, seventeen phosphates, along with one sulfate (gypsum), were recognized as secondary products of guano decay ...


Examination Of The Climate Factors That Reduced Wheat Yield In Northwest India During The 2000s, Avik Mukherjee, Shih-Yu (Simon) Wang, Parichart Promchote 2019 Utah State University

Examination Of The Climate Factors That Reduced Wheat Yield In Northwest India During The 2000s, Avik Mukherjee, Shih-Yu (Simon) Wang, Parichart Promchote

Shih-Yu (Simon) Wang

In India, a significant reduction of wheat yield would cause a widespread impact on food security for 1.35 billion people. The two highest wheat producing states, Punjab and Haryana in northern India, experienced a prolonged period of anomalously low wheat yield during 2002–2010. The extent of climate variability and change in influencing this prolonged reduction in wheat yield was examined. Daily air temperature (Tmax and Tave) was used to calculate the number of days above optimum temperature and growing degree days (GDD) anomaly. Two drought indices, the standard precipitation and evapotranspiration index and the radiation-based precipitation ...


The Modern Mississippi: Provenance Indicators And Human Impact, Brittney Gregory 2019 Louisiana State University and Agricultural and Mechanical College

The Modern Mississippi: Provenance Indicators And Human Impact, Brittney Gregory

Brittney Gregory

No abstract provided.


Nitrogen Fertilizer Suppresses Mineralization Of Soil Organic Matter In Maize Agroecosystems, Navreet K. Mahal, William R. Osterholz, Fernando E. Miguez, Hanna J. Poffenbarger, John E. Sawyer, Daniel C. Olk, Sotirios V. Archontoulis, Michael J. Castellano 2019 Iowa State University

Nitrogen Fertilizer Suppresses Mineralization Of Soil Organic Matter In Maize Agroecosystems, Navreet K. Mahal, William R. Osterholz, Fernando E. Miguez, Hanna J. Poffenbarger, John E. Sawyer, Daniel C. Olk, Sotirios V. Archontoulis, Michael J. Castellano

John E. Sawyer

The possibility that N fertilizer increases soil organic matter (SOM) mineralization and, as a result, reduces SOM stocks has led to a great debate about the long-term sustainability of maize-based agroecosystems as well as the best method to estimate fertilizer N use efficiency (FNUE). Much of this debate is because synthetic N fertilizer can positively or negatively affect SOM mineralization via several direct and indirect pathways. Here, we test a series of hypotheses to determine the direction, magnitude, and mechanism of N fertilizer effect on SOM mineralization and discuss the implications for methods to estimate FNUE.Wemeasured the effect of ...


Nitrogen Fertilizer Suppresses Mineralization Of Soil Organic Matter In Maize Agroecosystems, Navreet K. Mahal, William R. Osterholz, Fernando E. Miguez, Hanna J. Poffenbarger, John E. Sawyer, Daniel C. Olk, Sotirios V. Archontoulis, Michael J. Castellano 2019 Iowa State University

Nitrogen Fertilizer Suppresses Mineralization Of Soil Organic Matter In Maize Agroecosystems, Navreet K. Mahal, William R. Osterholz, Fernando E. Miguez, Hanna J. Poffenbarger, John E. Sawyer, Daniel C. Olk, Sotirios V. Archontoulis, Michael J. Castellano

Michael Castellano

The possibility that N fertilizer increases soil organic matter (SOM) mineralization and, as a result, reduces SOM stocks has led to a great debate about the long-term sustainability of maize-based agroecosystems as well as the best method to estimate fertilizer N use efficiency (FNUE). Much of this debate is because synthetic N fertilizer can positively or negatively affect SOM mineralization via several direct and indirect pathways. Here, we test a series of hypotheses to determine the direction, magnitude, and mechanism of N fertilizer effect on SOM mineralization and discuss the implications for methods to estimate FNUE.Wemeasured the effect of ...


Substrate Influences Turtle Nest Temperature, Incubation Period, And Offspring Sex Ratio In The Field, Timothy S. Mitchell, Fredric J. Janzen 2019 Iowa State University

Substrate Influences Turtle Nest Temperature, Incubation Period, And Offspring Sex Ratio In The Field, Timothy S. Mitchell, Fredric J. Janzen

Fredric Janzen

Temperature-dependent sex determination, where egg incubation temperature irreversibly determines offspring sex, is a common sex-determining mechanism in reptiles. Weather is the primary determinant of temperature in reptile nests, yet the effects of weather are mediated through the nest microhabitat selected by the mother (e.g., overstory canopy cover). One potentially important aspect of the nest microhabitat is the physical substrate used for nesting. However, the influence of substrate type on nest temperature and offspring sex determination has never been experimentally assessed in the field. We incubated eggs of Painted Turtles (Chrysemys picta) in three substrate types similar to those commonly ...


Mississippian-Devonian Black Shales Of Kentucky: East-West Transect In Five Cores From The Appalachian Basin To The Illinois Basin, Patrick J. Gooding, Frank R. Ettensohn 2019 University of Kentucky

Mississippian-Devonian Black Shales Of Kentucky: East-West Transect In Five Cores From The Appalachian Basin To The Illinois Basin, Patrick J. Gooding, Frank R. Ettensohn

Kentucky Geological Survey Map and Chart

Devonian-Mississippian black shales are widespread across North America and underlie nearly 70 percent of Kentucky (Kepferle and Roen, 1981; Ettensohn and others, 1988). These black-shale units are among the most thoroughly investigated format ions in the commonwealth, because t hey have sourced most of t he conventional hydrocarbons (Gooding and Ettensohn, 2008; Gooding, 2013), have been major producers of gas in both the Illinois and Appalachian Basins, and have major potential as unconventional producers in both basins. In fact, maturation indicators such as vitrinite reflectance and total organic carbon, from both basins, show that the shales are most ly mature ...


Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya 2019 University of Dayton

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Umesh K. Haritashya

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they ...


Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek 2019 University of Exeter

Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek

Umesh K. Haritashya

Despite recent research identifying a clear anthropogenic impact on glacier recession, the effect of recent climate change on glacier-related hazards is at present unclear. Here we present the first global spatio-temporal assessment of glacial lake outburst floods (GLOFs) focusing explicitly on lake drainage following moraine dam failure. These floods occur as mountain glaciers recede and downwaste. GLOFs can have an enormous impact on downstream communities and infrastructure. Our assessment of GLOFs associated with the rapid drainage of moraine-dammed lakes provides insights into the historical trends of GLOFs and their distributions under current and future global climate change. We observe a ...


Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya, Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi 2019 University of Dayton

Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya, Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi

Umesh K. Haritashya

Glacier recession driven by climate change produces glacial lakes, some of which are hazardous. Our study assesses the evolution of three of the most hazardous moraine-dammed proglacial lakes in the Nepal Himalaya—Imja, Lower Barun, and Thulagi. Imja Lake (up to 150 m deep; 78.4 x 106 m3 volume; surveyed in October 2014) and Lower Barun Lake (205 m maximum observed depth; 112.3 x 106 m3 volume; surveyed in October 2015) are much deeper than previously measured, and their readily drainable volumes are slowly growing. Their surface areas have been increasing at an accelerating ...


Supplemental Data For 'Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya', Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi 2019 University of Dayton

Supplemental Data For 'Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya', Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi

Umesh K. Haritashya

Supplementary data for the article "Evolution and Controls of Large Glacial Lakes in the Nepal Himalaya"


Substrate Influences Turtle Nest Temperature, Incubation Period, And Offspring Sex Ratio In The Field, Timothy S. Mitchell, Fredric J. Janzen 2019 Iowa State University

Substrate Influences Turtle Nest Temperature, Incubation Period, And Offspring Sex Ratio In The Field, Timothy S. Mitchell, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Temperature-dependent sex determination, where egg incubation temperature irreversibly determines offspring sex, is a common sex-determining mechanism in reptiles. Weather is the primary determinant of temperature in reptile nests, yet the effects of weather are mediated through the nest microhabitat selected by the mother (e.g., overstory canopy cover). One potentially important aspect of the nest microhabitat is the physical substrate used for nesting. However, the influence of substrate type on nest temperature and offspring sex determination has never been experimentally assessed in the field. We incubated eggs of Painted Turtles (Chrysemys picta) in three substrate types similar to those commonly ...


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