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Seismic Anisotropy Of The Upper Crust In The Mountain Ranges Of Taiwan From The Taiger Explosion Experiment, Kuo-Chen Hao, Piotr Sroda, Francis T. Wu, Chien-Ying Wang, Yao-Wen Kuo 2013 Binghamton University--SUNY

Seismic Anisotropy Of The Upper Crust In The Mountain Ranges Of Taiwan From The Taiger Explosion Experiment, Kuo-Chen Hao, Piotr Sroda, Francis T. Wu, Chien-Ying Wang, Yao-Wen Kuo

Earth Sciences Faculty Scholarship

Taiwan is known as a strongly anisotropic region observed from SKS 1 - 2 s delay time and other teleseismic phases. An estimate of the crustal contribution to the total anisotropy from the foliated Central Range is essential to understanding the overall teleseismic results. We used P wave arrivals from the dense seismic arrays deployed during the TAIGER active source experiments and the permanent broadband seismic stations to determine the crustal anisotropy. From the arrival time analysis as a function of azimuth, we detected a clear cos(2 theta) pattern. The strength of the crustal anisotropy (0 - 15 km depth) …


Melt Generation Beneath Arctic Ridges: Implications From Ule, Lynne J. Elkins, K. W. Sims, J. Prytulak, J. Blichert-Toft, T. Elliott, J. Blusztajn, S. Fretzdorff,, M. Reagan, K. Haase, S. Humphris, J.-G. Schilling 2013 Bryn Mawr College

Melt Generation Beneath Arctic Ridges: Implications From Ule, Lynne J. Elkins, K. W. Sims, J. Prytulak, J. Blichert-Toft, T. Elliott, J. Blusztajn, S. Fretzdorff,, M. Reagan, K. Haase, S. Humphris, J.-G. Schilling

Geology Faculty Research and Scholarship

We present new 238U-230Th-226Ra-210Pb, 235U-231Pa, and Nd, Sr, Hf, and Pb isotope data for the slow- to ultraslow-spreading Mohns, Knipovich, and Gakkel Ridges. Combined with previous work, our data from the Arctic Ridges cover the full range of axial depths from the deep northernmost Gakkel Ridge shallowing upwards to the Knipovich, Mohns, and Kolbeinsey Ridges north of Iceland. Age-constrained samples from the Mohns and Knipovich Ridges have (230Th/238U) activity ratios ranging from 1.165 to 1.30 and 1.101 to 1.225, respectively. The high 230Th excesses of …


The Urban Heat Island And Its Influence On Precipitation In Denver, Colorado, Diana Thunen 2013 University of Denver

The Urban Heat Island And Its Influence On Precipitation In Denver, Colorado, Diana Thunen

Electronic Theses and Dissertations

Anthropogenic modification of the climate is an unintended yet serious effect of urbanization and it is happening in every city across the globe in the form of the urban heat island. The purpose of this study was to see if Denver, Colorado exhibits evidence of an urban heat island using meteorological data and if there has been a change in precipitation amounts since the urbanization of the city. It was concluded that Denver, Colorado does have an urban heat island that varies seasonally throughout the year with an average magnitude of 3.57°C during the day and 3.82°C at night. The …


Biostratigraphy Of The Halgaito Formation, Cutler Group Near Mexican Hat, San Juan County, Utah, Kimberly Marie Scott 2013 California State University, San Bernardino

Biostratigraphy Of The Halgaito Formation, Cutler Group Near Mexican Hat, San Juan County, Utah, Kimberly Marie Scott

Theses Digitization Project

The purpose of this thesis is to develop a better understanding of the paleontology and biostratigraphy of the Halgaito Formation and the position of the Carboniferous-Permian Boundary (CPB) within the Halgaito Formation which would provide useful data that can be extrapolated to other terrestrial ecosystems of the southwestern United States of America that are of comparable age.


Scales Over Shale: How Pennsylvania Got Fracked, Carlo E. Sica 2013 Syracuse University

Scales Over Shale: How Pennsylvania Got Fracked, Carlo E. Sica

Geography and the Environment - Theses

Shale gas has become one of Pennsylvania's major resources in recent years and the gas boom has proceeded in spite of uncertainty over the environmental risks of its production process. This thesis argues that location alone cannot explain why shale gas boomed in Pennsylvania. Using interviews with corporate and state executives, I argue that the scalar dimensions of the neoliberal environmental governance of shale gas were critical to understanding why shale gas boomed in Pennsylvania. These actors supported the preemption of local scales of governance by the state as a scalar fix for capital accumulation from shale gas development. They …


Probabilistic Modeling Of Rainfall Induced Landslide Hazard Assessment In San Juan La Laguna, Sololá, Guatemala, Patrice F. Cobin 2013 Michigan Technological University

Probabilistic Modeling Of Rainfall Induced Landslide Hazard Assessment In San Juan La Laguna, Sololá, Guatemala, Patrice F. Cobin

Dissertations, Master's Theses and Master's Reports - Open

The municipality of San Juan La Laguna, Guatemala is home to approximately 5,200 people and located on the western side of the Lake Atitlán caldera. Steep slopes surround all but the eastern side of San Juan. The Lake Atitlán watershed is susceptible to many natural hazards, but most predictable are the landslides that can occur annually with each rainy season, especially during high-intensity events. Hurricane Stan hit Guatemala in October 2005; the resulting flooding and landslides devastated the Atitlán region. Locations of landslide and non-landslide points were obtained from field observations and orthophotos taken following Hurricane Stan. This study used …


Understanding And Managing Karst Water Resources In Belize: Case Studies Of Both Past And Present In A Changing Climate, Jason S. Polk, Leslie North, Ben Miller, Jonathan Oglesby, Kegan McClanahan, Lowell Neeper, Aaron Holland, Bernie Strenecky 2013 Western Kentucky University

Understanding And Managing Karst Water Resources In Belize: Case Studies Of Both Past And Present In A Changing Climate, Jason S. Polk, Leslie North, Ben Miller, Jonathan Oglesby, Kegan Mcclanahan, Lowell Neeper, Aaron Holland, Bernie Strenecky

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Belize is a developing country that faces water resource issues in the forms of both quality and quantity, stemming from a long history of environmental stress and population threats, from the ancient Maya to present. Belize’s karst landscape, which comprises a large part of the country from the coast to the Maya Mountains, is characterized by springs, caves, sinkholes, and aquifers systems formed from the dissolution of carbonate (limestone, dolomite) rock. This research presents several different case studies, spanning from the ancient Maya and issues with drought to modern communities that rely on groundwater resources quickly being depleted. Past drought …


Ua12/13 Big Red, Small Planet, Christian Ryan-Downing , editor, Leslie North , editor 2013 Western Kentucky University

Ua12/13 Big Red, Small Planet, Christian Ryan-Downing , Editor, Leslie North , Editor

Sustainability Publications and Resources

At WKU, “The Spirit Makes the Master”. Our commitment to continuous improvement is clearly reflected in our sustainability efforts. WKU’s commitment to sustainability, whether demonstrated in campus operations or in educational programs, helps to ensure that our graduates are prepared to address the complicated environmental, social and economic issues we face today. They will be able to think critically, solve problems creatively and be engaged citizens. If that’s all we accomplish then we will have achieved great success. But our sustainability commitment pays dividends, as it also leads us to reduce our environmental footprint, practice social responsibility, and conserve natural …


Middle And Late Devonian New Albany Shale In The Kentucky Geological Survey Marvin Blan No. 1 Well, Hancock County, Kentucky, Brandon C. Nuttall 2013 University of Kentucky

Middle And Late Devonian New Albany Shale In The Kentucky Geological Survey Marvin Blan No. 1 Well, Hancock County, Kentucky, Brandon C. Nuttall

Report of Investigations--KGS

A 30-ft section of core was recovered in the Grassy Creek Member of the New Albany Shale in the Kentucky Geological Survey Marvin Blan No. 1 well, Hancock County, Ky. (permit 104925, API No. 16091013960000). Analysis characterized the New Albany Shale as a regional seal for preventing vertical migration of carbon dioxide stored in deeper zones, as a natural gas reservoir, and for its potential for enhanced gas recovery and sequestration of carbon dioxide. A show of natural gas at the top of the New Albany Shale was encountered during drilling. Core was recovered in an aluminum sleeve cut into …


Evaporite Karst And Hydrogeology Of The Castile Formation: Culberson County, Texas And Eddy County, New Mexico, Kevin W. Stafford 2013 College of Sciences and Mathematics, Department of Geology, Stephen F. Austin State University

Evaporite Karst And Hydrogeology Of The Castile Formation: Culberson County, Texas And Eddy County, New Mexico, Kevin W. Stafford

Faculty Publications

Karst development in Permian Castile evaporites has resulted in complex speleogenetic evolution with multiple phases of diagenetic overprinting. More than 10,000 surficial features, primarily sinkholes, occur throughout Culberson County, Texas, and Eddy County, New Mexico, based on GIS-analyses where laminated Castile sulfates crop out. Cave development is largely the result of hypogene processes, where ascending fluids from the underlying Bell Canyon Formation migrate near vertically through the Castile Formation, creating caves up to 100 meters deep and over 500 meters long, which have been breached through a combination of collapse and surface denudation. Numerous small and laterally limited epigene features …


Clastic Sinkhole And Pseudokarst Development In East Texas, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Wesley A. Brown 2013 College of Sciences and Mathematics, Department of Geology, Stephen F. Austin State University

Clastic Sinkhole And Pseudokarst Development In East Texas, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Wesley A. Brown

Faculty Publications

Pseudokarst development in East Texas is controlled primarily by a combination of suffosion and preferential flow paths, often creating small ephemeral sinkholes but occasionally persistent features develop in more indurated facies. Pseudokarst occurs in Claiborne (Eocene) strata in Angelina, Cherokee, Nacogdoches, Panola, Rusk, San Augustine and Shelby counties. Strata consist of interbedded fine- and coarse-grained clastics with variable cementation and associated permeabilities.


Caves And Karst Hydrology Of The Mariana Islands (Abstract), Kevin W. Stafford 2013 College of Sciences and Mathematics, Department of Geology, Stephen F. Austin State University

Caves And Karst Hydrology Of The Mariana Islands (Abstract), Kevin W. Stafford

Faculty Publications

Abstract Attached


Assessment Of Coal Geology, Resources, And Reserve Base In The Powder River Basin, Wyoming And Montana, James A. Luppens, David C. Scott, Lee M. Osmonson, Jon E. Haacke, Paul E. Pierce 2013 U.S. Geological Survey

Assessment Of Coal Geology, Resources, And Reserve Base In The Powder River Basin, Wyoming And Montana, James A. Luppens, David C. Scott, Lee M. Osmonson, Jon E. Haacke, Paul E. Pierce

United States Geological Survey: Publications

Using a geology-based assessment methodology, the U.S. Geological Survey estimated in-place resources of 1.07 trillion short tons of coal in the Powder River Basin, Wyoming and Montana. Of that total, with a maximum stripping ratio of 10:1, recoverable coal was 162 billion tons. The estimate of economically recoverable resources was 25 billion tons.


Modeling Rain-Fed Maize Vulnerability To Droughts Using The Standardized Precipitation Index From Satellite Estimated Rainfall-Southern Malawi Case Study, Harikishan Jayanthi, Gregory J. Husak, Chris Funk, Tamuka Magadzire, Adams Chavula, James P. Verdin 2013 University of California, Santa Barbara

Modeling Rain-Fed Maize Vulnerability To Droughts Using The Standardized Precipitation Index From Satellite Estimated Rainfall-Southern Malawi Case Study, Harikishan Jayanthi, Gregory J. Husak, Chris Funk, Tamuka Magadzire, Adams Chavula, James P. Verdin

United States Geological Survey: Staff Publications

During 1990s, disaster risk reduction emerged as a novel, proactive approach to managing risks from natural hazards. The World Bank, USAlD, and other international donor agencies began making efforts to mainstream disaster risk reduction in countries whose population and economies were heavily dependent on rain-fed agriculture. This approach has more significance in light of the increasing climatic hazard patterns and the climate scenarios projected for different hazard prone countries in the world. The Famine Early Warning System Network (FEWS NET) has been monitoring the food security issues in the sub-Saharan Africa, Asia and in Haiti. FEWS NET monitors the rainfall …


Characterizing Ledaps Surface Reflectance Products By Comparisons With Aeronet, Field Spectrometer, And Modis Data, T.K. Maiersperger, P.L. Scaramuzza, L. Leigh, S. Shrestha, K.P. Gallo, C.B. Jenkerson, J.L. Dwyer 2013 U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center

Characterizing Ledaps Surface Reflectance Products By Comparisons With Aeronet, Field Spectrometer, And Modis Data, T.K. Maiersperger, P.L. Scaramuzza, L. Leigh, S. Shrestha, K.P. Gallo, C.B. Jenkerson, J.L. Dwyer

United States Geological Survey: Staff Publications

This study provides a baseline quality check on provisional Landsat Surface Reflectance (SR) products as generated by the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center using Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) software. Characterization of the Landsat SR products leveraged comparisons between aerosol optical thickness derived from LEDAPS and measured by Aerosol Robotic Network (AERONET), as well as reflectance correlations with field spectrometer and Moderate Resolution Imaging Spectroradiometer (MODIS) data. Results consistently indicated similarity between LEDAPS and alternative data products in longer wavelengths over vegetated areas with no adjacent water, while less reliable performance was …


Radiocarbon Dating Late Quaternary Loess Deposits Using Small Terrestrial Gastropod Shells, Jeffrey S. Pigati, John McGeehin, Daniel R. Muhs, E. Arthur Bettis III 2013 U.S. Geological Survey, Denver Federal Center

Radiocarbon Dating Late Quaternary Loess Deposits Using Small Terrestrial Gastropod Shells, Jeffrey S. Pigati, John Mcgeehin, Daniel R. Muhs, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

No abstract provided.


Preliminary Summary Of Water Resource Investigations During 2012 At Timpanogos Cave National Monument, Utah, Lee J. Florea, Chelsie R. Dugan, Camille McKinney 2013 Ball State University

Preliminary Summary Of Water Resource Investigations During 2012 At Timpanogos Cave National Monument, Utah, Lee J. Florea, Chelsie R. Dugan, Camille Mckinney

National Cave and Karst Management Symposium 2013

This manuscript considers the hydrology and geochemistry of water resources within Timpanogos Cave National Monument in American Fork, Utah. In particular, data are presented for five cave pools within the Monument and the American Fork River that flows through the Monument. Two independent dye trace attempts in this study have not established a connection between the surface near the canyon rim at the south border of the Monument and the cave pools or the river. Ion chemistry of the pools reveals elevated sulfate concentrations. Analysis of sulfate and other reaction products suggests the possibility of combined carbonic and sulfuric acids …


Modeling The Metamorphic History Of Ultrahigh Pressure Rocks: Western China, Jesse Walters 2013 Central Washington University

Modeling The Metamorphic History Of Ultrahigh Pressure Rocks: Western China, Jesse Walters

Undergraduate Honors Theses

In order to better understand metamorphism during continent-continent collision, the pressure-temperature history of a garnet-k:yanite paragniess from the Dulan region of the N. Qaidam high-pressure (HP)/ ultrahigh-pressure (UHP) belt is modeled. The gneiss contains the assemblage Bt + Pl + Kfs + Grt + Ky + Qtz + Rt + Ap. An equilibrium assemblage diagram constructed for the sample's pelitic bulk composition predicts the observed assemblage to form at ~ 11-15 kbar and ~810-870 °C. The diagram predicts predicts ~2-8 vol% melt in the observed assemblage. Predicted mineral abundances closely match observed values, with 8-18 vol % garnet and 0-10 …


Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar 2013 Central Washington University

Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar

Undergraduate Honors Theses

The eastern portion of Washington State's Cascade Range is a place not previously examined for rock glaciers, due to proximity to the Pacific Ocean and its associated marine­-influenced climate. The objectives of this study were to determine spatial, activity, and genesis patterns, and paleoclimatic implications of Eastern Cascade rock glaciers. Using Google Earth, I found l 03 rock glaciers in the study area. Rock glaciers are more common further east of the Cascade crest and more north in latitude, with the largest concentrations occurring east of Lake Chelan (22) and in the Pasayten Wilderness (28) in the North Cascades. None …


The Tilt Of The Boron Triangle In Tourmaline, Charles J. Badgerow 2013 Eastern Michigan University

The Tilt Of The Boron Triangle In Tourmaline, Charles J. Badgerow

Senior Honors Theses and Projects

The tourmaline mineral group has a highly complex chemical composition and provides a wealth of information on Earth's processes. Past research has revealed numerous mysteries regarding the structure of the boron triangle within tourmaline, especially as it bonds to the Z- and Z'- cation sites. Although the Z- and Z' - are nominally the same site, the Z'-site has a greater effect on the stereochemistry of the boron triangle. Further, the Z' -site has a shorter bond-length with the boron triangle than the Z-site. We hypothesize that this variation affects the stereochemistry of the boron triangle, and have analyzed a …


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