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Modeling Urban Hydrology: A Comparison Of New Urbanist And Traditional Neighborhood Design Surface Runoff, C. Andrew Day, Keith A. Bremer Ph.D. Jan 2013

Modeling Urban Hydrology: A Comparison Of New Urbanist And Traditional Neighborhood Design Surface Runoff, C. Andrew Day, Keith A. Bremer Ph.D.

Geosciences Faculty Publications

Urban development affects the amount of potential surface runoff generated during storms by changing the amount of impervious cover across the landscape. However, the degree of surface runoff alteration depends on the type of urban development in place. New urbanist developments are designed with higher densities and encourage a diversity of land uses, while traditional neighborhood developments have a monotone land use pattern with medium-to- low densities. Two neighborhoods within the city of Austin, Texas- Mueller, a new urbanist development, and Circle C Ranch, a traditional neighborhood development- were used to study the effect of development type on potential surface …


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

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 …


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

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 …


A Comprehensive Approach To Alluvial Fan Management: A Case Study Of Travertine Point, Coachella Valley, Jason Joseph Thomas Jan 2013

A Comprehensive Approach To Alluvial Fan Management: A Case Study Of Travertine Point, Coachella Valley, Jason Joseph Thomas

Theses Digitization Project

The purpose of this project is to make a contribution towards improving the sustainability of developments (master plan communities) on alluvial fans. To do this, the authors intent is to further the goals of the Integrated Approach for Sustainable Development on Alluvial Fans Task Force.


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 Jan 2013

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 Jan 2013

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 …


The Contribution Of Small Anthropogenic Particulates (Sap) To The Sediment Load Of A Major Ephemeral Fluvial System, Santa Ana River (Sar), Southern California, Junjie Shen Jan 2013

The Contribution Of Small Anthropogenic Particulates (Sap) To The Sediment Load Of A Major Ephemeral Fluvial System, Santa Ana River (Sar), Southern California, Junjie Shen

Theses Digitization Project

This research was undertaken to explore the distribution of small anthropogenic particulates (SAP) in the Santa Ana River (SAR), and to determine the contribution of SAP to the sediment load of the SAR. SAP have never been documented before in the fluvial systems, especially in Southern California. This project will effectively establish a baseline for future changes in SAP for environmental monitoring and regulations.


Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin Jan 2013

Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin

High Plains Regional Climate Center: Staff Publications

A cost-effective approach was used to investigate the relationship between emission of the greenhouse gases (GHG), namely, CO2, CH4, and N2O and energy fluxes from a swine waste lagoon. Energy fluxes were calculated using the Penman method. The energy fluxes showed a diurnal pattern as expected of such fluxes. We found that air temperature and latent energy, lagoon surface temperature and solar radiation, as well as air temperature and wind speed can be used to predict for CO2, CH4, and N2O emissions, respectively. Comparison of observed and predicted …


Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson Jan 2013

Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson

High Plains Regional Climate Center: Staff Publications

This document is one of series of regional climate descriptions designed to provide input that can be used in the development of the National Climate Assessment (NCA). As part of a sustained assessment approach, it is intended that these documents will be updated as new and well-vetted model results are available and as new climate scenario needs become clear. It is also hoped that these documents (and associated data and resources) are of direct benefit to decision makers and communities seeking to use this information in developing adaptation plans.

There are nine reports in this series, one each for eight …


Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch Jan 2013

Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS), in cooperation with the North Dakota Department of Transportation and the North Dakota State Water Commission, completed hydrographic surveys at six Missouri River bridges and one Yellowstone River bridge during the 2011 flood of the Missouri River system. Bridges surveyed are located near the cities of Cartwright, Buford, Williston, Washburn, and Bismarck, N. Dak. The river in the vicinity of the bridges and the channel through the city of Bismarck, N. Dak., were surveyed. The hydrographic surveys were conducted using a high-resolution multibeam echosounder (MBES), the RESON SeaBatTM 7125, during June 6–9 and June …


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 Jan 2013

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 Jan 2013

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 Jan 2013

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 …


Old Dominion University Climate Change And Sea Level Rise Initiative, Winter 2013, Larry P. Atkinson (Editor) Jan 2013

Old Dominion University Climate Change And Sea Level Rise Initiative, Winter 2013, Larry P. Atkinson (Editor)

CCSLRI Newsletters

Winter 2013 Newsletter of the Old Dominion University Climate Change and Sea Level Rise Initiative


Summer Co2 Evasion From Streams And Rivers In The Kolyma River Basin, North-East Siberia, Blaize A. Denfeld, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes Jan 2013

Summer Co2 Evasion From Streams And Rivers In The Kolyma River Basin, North-East Siberia, Blaize A. Denfeld, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes

Geography

Inland water systems are generally supersaturated in carbon dioxide (CO2) and are increasingly recognized as playing an important role in the global carbon cycle. The Arctic may be particularly important in this respect, given the abundance of inland waters and carbon contained in Arctic soils; however, a lack of trace gas measurements from small streams in the Arctic currently limits this understanding.We investigated the spatial variability of CO2 evasion during the summer low-flow period from streams and rivers in the northern portion of the Kolyma River basin in north-eastern Siberia. To this end, partial pressure of carbon dioxide (pCO2) and …


Five Year Carbon Storage Analysis In The Gordon Natural Area, Joy Fritschle, Chad Hudson, Catherine Spahr, Andy Tamez Jan 2013

Five Year Carbon Storage Analysis In The Gordon Natural Area, Joy Fritschle, Chad Hudson, Catherine Spahr, Andy Tamez

Forest Carbon Storage Study Documents

The Gordon Natural Area (GNA) serves as a natural laboratory for a range of class research projects. In a Geography Field Methods course led by Dr. Fritschle, students established five permanent carbon-study plots in 2008. Since then, students have returned to these plots to measure the carbon stock of standing trees in five plots located along a topographic gradient: floodplain, ridge-top, lower mid-slope, mid-slope and upper mid-slope. Using U.S. Forest Service established guidelines, all trees greater than 5 cm and up to 73 cm in diameter at breast height (DBH) were measured and identified within each 40 m circular plot. …


Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar Jan 2013

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 Jan 2013

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 …


Chemostratigraphy Of The Early Pliocene Diatomite Interval From Mis And-1b Core (Antarctica): Paleoenvironment Implications, Giovanna Scopelliti, Adriana Bellanca, Donata Monien, Gerhard Kuhn Jan 2013

Chemostratigraphy Of The Early Pliocene Diatomite Interval From Mis And-1b Core (Antarctica): Paleoenvironment Implications, Giovanna Scopelliti, Adriana Bellanca, Donata Monien, Gerhard Kuhn

ANDRILL Research and Publications

The AND-1B drill core (1285 m-long) was recovered, inside the ANDRILL (ANtarctic geological DRILLing) Program, during the austral summer of 2006/07 from beneath the floating McMurdo Ice Shelf. Drilling recovered a stratigraphic succession of alternating diamictites, diatomites and volcaniclastic sediments spanning about the last 14 Ma. A core portion between 350 and 480 mbsf, including a 80 m-thick diatomite interval recording the early Pliocene warming event, was investigated in term of opal biogenic content and element geochemistry. Across the diatomite interval, in spite of the lithological uniformity, a fluctuating biogenic opal profile mirrors the δ18O record, testifying a decrease in …


Geo402/585: Field Methods; Labs 4-5 Gordon Natural Area Carbon Stock Pilot Study, Joy Fritschle Jan 2013

Geo402/585: Field Methods; Labs 4-5 Gordon Natural Area Carbon Stock Pilot Study, Joy Fritschle

Gordon Natural Area-related Curricula Documents

No abstract provided.


Challenges Of Cave Management In A Developing Country: A Case Study Of Grotte Marie-Jeanne, Departemente Sud, Haiti, Patricia N. Kambesis, Brian Oakes, Michael Lace Jan 2013

Challenges Of Cave Management In A Developing Country: A Case Study Of Grotte Marie-Jeanne, Departemente Sud, Haiti, Patricia N. Kambesis, Brian Oakes, Michael Lace

National Cave and Karst Management Symposium 2013

As with many developing countries,Haiti has environmental, economic and cultural challenges that complicate natural resource management. Karst landscapes dominate Haiti and caves are abundant as recent cave and karst inventory data indicate. Though the caves and karst are subject to environmental challenges they also provide the potential for the development of tourism that would improve local economic conditions. There are 500 documented caves in Haiti of which, five are show caves. Of those, only one, Grotte Marie-Jeanne, located in Port-ấ -Piment in Departement Sud, has a structured cave management plan that addresses identification of cave resources, visitor access, interpretive guidelines, …


Identifying Ditch Geometry And Top Of The Bank Location Using Airborne Lidar Point Cloud, Naime Celik Jan 2013

Identifying Ditch Geometry And Top Of The Bank Location Using Airborne Lidar Point Cloud, Naime Celik

Open Access Theses

The geometry of agricultural drainage ditches is very important in crop production as it impacts drainage of cropland and affects vegetation and soil erosion along the banks of the ditches. Thus, implementation of water conservation and management practices in engineered and natural ditches necessitates determination of ditch geometry along the reach of the ditch. This study explores the use of airborne commercial Light Detection and Ranging (LiDAR) technology to identify the top of the ditch banks. The method was developed to obtain the normalized cross sectional shape of the ditch using one-dimensional spline fits to ground classified points from the …


Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar Jan 2013

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 103 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 were …


Modeling Bedrock Mining Hotspots Within The Ouachita National Forest, Arkansas, Stephanie H. Mehlhope Jan 2013

Modeling Bedrock Mining Hotspots Within The Ouachita National Forest, Arkansas, Stephanie H. Mehlhope

Theses and Dissertations--Geography

This study, concentrating on the Ouachita Mountain Range in western-central Arkansas, extends prior work on treethrows and their influence on soil development in the region by supplying a method of determining hotspots of bedrock mining by treethrow. Binary logistic regression analysis was employed to determine the abiotic and biotic factors that are highly correlated with the rate of bedrock detachment found in uprooted rootwads from three study sites within the Ouachita National Forest. The produced logistic regression models suggest topographic factors, tree specific characteristics, as well as the local geology and soil characteristics all have a significant effect upon the …


Revisiting The Genesis Of Red Mediterranean Soils, Nicolas Fedoroff, Marie-Agnes Courty Jan 2013

Revisiting The Genesis Of Red Mediterranean Soils, Nicolas Fedoroff, Marie-Agnes Courty

Turkish Journal of Earth Sciences

This work, aside from being a classical discussion on the processes of rubefaction and illuviation, is an attempt to cross the abundant literature on red Mediterranean soils (RMSs) written by pedologists, and also by paleopedologists and geologists, with the climatic frame established by paleoclimatologists for the Quaternary. Such an approach leads us to consider that the development of the RMSs was discontinuous, occurring during periods of environmental stability, i.e. interglacials, characterized by a humid climate (precipitations exceeding evapotranspiration) with dry and hot summers. The impact of glacial intervals on the RMS covers is presently only partially documented. Aeolian processes during …


Coastal Inundation Due To Sea Level Rise And Extreme Sea State And Its Potential Impacts: Çukurova Delta Case, Özlem Si̇mav, Dursun Zafer Şeker, Cem Gazi̇oğlu Jan 2013

Coastal Inundation Due To Sea Level Rise And Extreme Sea State And Its Potential Impacts: Çukurova Delta Case, Özlem Si̇mav, Dursun Zafer Şeker, Cem Gazi̇oğlu

Turkish Journal of Earth Sciences

With the rising sea level becoming a more pressing issue to coastal areas, a comprehensive analysis has been conducted to assess the vulnerability of the Çukurova Delta under the projected inundation by the end of the century. The level of inundation was estimated from a multimission satellite altimetry sea level anomaly and significant wave height data between September 1992 and February 2012. Superposed to the clear annual oscillation with 6.2 cm amplitude peaking around the beginning of October, the mean sea level signal exhibits a positive trend of 3.4 ± 0.1 mm/year over the altimetric data period. The extreme wave …


Comparison Of Pcr And Quantitative Real-Time Pcr Methods For The Characterization Of Ruminant And Cattle Fecal Pollution Sources, Meredith R. Raith, Catherine A. Kelty, John F. Griffith, Alexander Schriewer, Stefan Wuertz, Sophie Mieszkin, Michele Gourmelon, Georg H. Reischer, Andreas H. Farnleitner, Jared S. Ervin, Patricia A. Holden, Darcy L. Ebentier, Jennifer A. Jay, Dan Wang, Alexandria B. Boehm, Tiong Gim Aw, Joan B. Rose, E. Balleste, W.G. Meijer, Mano Sivaganesan, Orin C. Shanks Jan 2013

Comparison Of Pcr And Quantitative Real-Time Pcr Methods For The Characterization Of Ruminant And Cattle Fecal Pollution Sources, Meredith R. Raith, Catherine A. Kelty, John F. Griffith, Alexander Schriewer, Stefan Wuertz, Sophie Mieszkin, Michele Gourmelon, Georg H. Reischer, Andreas H. Farnleitner, Jared S. Ervin, Patricia A. Holden, Darcy L. Ebentier, Jennifer A. Jay, Dan Wang, Alexandria B. Boehm, Tiong Gim Aw, Joan B. Rose, E. Balleste, W.G. Meijer, Mano Sivaganesan, Orin C. Shanks

United States Environmental Protection Agency: Publications

The State of California has mandated the preparation of a guidance document on the application of fecal source identification methods for recreational water quality management. California contains the fifth highest population of cattle in the United States, making the inclusion of cow-associated methods a logical choice. Because the performance of these methods has been shown to change based on geography and/or local animal feeding practices, laboratory comparisons are needed to determine which assays are best suited for implementation. We describe the performance characterization of two end-point PCR assays (CF128 and CF193) and five real-time quantitative PCR (qPCR) assays (Rum2Bac, BacR, …


Ice-Age Megafauna In Arctic Alaska: Extinction, Invasion, Survival, Daniel H. Mann, Pamela Groves, Michael L. Kunz, Richard E. Reanier, Benjamin V. Gaglioti Jan 2013

Ice-Age Megafauna In Arctic Alaska: Extinction, Invasion, Survival, Daniel H. Mann, Pamela Groves, Michael L. Kunz, Richard E. Reanier, Benjamin V. Gaglioti

United States Geological Survey: Staff Publications

Radical restructuring of the terrestrial, large mammal fauna living in arctic Alaska occurred between 14,000 and 10,000 years ago at the end of the last ice age. Steppe bison, horse, and woolly mammoth became extinct, moose and humans invaded, while muskox and caribou persisted. The ice age mega fauna was more diverse in species and possibly contained 6x more individual animals than live in the region today. Mega faunal biomass during the last ice age may have been 30x greater than present. Horse was the dominant species in terms of number of individuals. Lions, short-faced bears, wolves, and possibly grizzly …


Thermal History Of Nearly Metamict Zircon Of The Taza-Guercif Basin (Morocco) Revealed Using Scanning Electron Microscope High-Density Fission-Track Dating, Tyler Michael Izykowski Jan 2013

Thermal History Of Nearly Metamict Zircon Of The Taza-Guercif Basin (Morocco) Revealed Using Scanning Electron Microscope High-Density Fission-Track Dating, Tyler Michael Izykowski

Theses and Dissertations

Northwest Africa provides unique insight into a wide range of geologic processes throughout a vast portion of Earth's history. Moroccan geology in particular can provide valuable insight, from the formations of West Africa through the Eburnian orogeny (~2000 Ma), Gondwana during the Pan-African orogeny (~900-500 Ma), and Pangaea by means of the Hercynian (Variscan) orogeny (~400-300 Ma), to more recent crustal and climatic events, such as the Messinian salinity crisis (5.96-5.33 Ma). However, the current lack of western literature regarding this region presents a significant obstacle in understanding the aforementioned processes. Herein, I employ a new technique in zircon fission-track …


Determining The Sediment Source Area Through Petrographic Analysis Of The Hermosa Formation, Silverton, Southwestern Co, Kristina P. Pourtabib Jan 2013

Determining The Sediment Source Area Through Petrographic Analysis Of The Hermosa Formation, Silverton, Southwestern Co, Kristina P. Pourtabib

Undergraduate Honors Theses

The Pennsylvanian/Permian Hermosa Formation in southwestern Colorado is composed of arkosic sandstone, marine limestone, and shale that formed at a time when the region consisted of open-marine carbonate shelves and coastal plains. During the time of deposition, there were many tectonically active highlands in the region, including the Ancestral Rocky Mountains, San Luis Highlands, and the Uncompahgre, Emery, Zuni-Defiance-Kaibab Uplifts. Previous studies have attributed the source of the main sediment supply of the Hermosa Formation to the Uncompahgre branch of the Ancestral Rocky Mountains with smaller amounts of elastics from the Defiance-Zuni uplifts (Wengerd and Matheny, 1958; Wengerd and Strickland, …