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The Compass: A Shifting Paradigm, Larry E. Davis

The Compass: Earth Science Journal of Sigma Gamma Epsilon

No abstract provided.

Major Milestones In The Development Of Sigma Gamma Epsilon's Core Traditions, Richard L. Ford

The Compass: Earth Science Journal of Sigma Gamma Epsilon

No abstract provided.

Sigma Gamma Epsilon News And Information

The Compass: Earth Science Journal of Sigma Gamma Epsilon

No abstract provided.

An Aphelaspis Zone (Upper Cambrian, Paibian) Trilobite Faunule In The Central Conasauga River Valley, North Georgia, Usa, David R. Schwimmer

Faculty Bibliography

Middle and Upper Cambrian strata (Cambrian Series 3 and Furongian) in the southernmost Appalachians (Tennessee to Alabama) comprise the Conasauga Formation or Group. Heretofore, the youngest reported Conasauga beds in the Valley and Ridge Province of Georgia were of the late Middle Cambrian (Series 3: Drumian) Bolaspidella Zone, located on the western state boundary in the valley of the Coosa River. Two new localities sited eastward in the Conasauga River Valley, yield a diagnostic suite of trilobites from the Upper Cambrian Aphelaspis Zone. Very abundant, polymeroid trilobites at the primary locality are referable to Aphelaspis brachyphasis, which is a species …

The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Post-Speleogenetic Biogenic Modification Of Gomantong Caves, Sabah, Borneo, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

The Gomantong cave system of eastern Sabah, Malaysia, is well-known as an important site for harvesting edible bird-nests and, more recently, as a tourist attraction. Although the biology of the Gomantong system has been repeatedly studied, very little attention has been given to the geomorphology. Here, we report on the impact of geobiological modification in the development of the modern aspect of the cave, an important but little recognized feature of tropical caves. Basic modeling of the metabolic outputs from bats and birds (CO₂, H₂O, heat) reveals that post-speleogenetic biogenic corrosion can erode bedrock by between …

Drought Monitoring: Historical And Current Perspectives, Michael J. Hayes, Mark D. Svoboda, Brian D. Wardlow, Martha C. Anderson, Felix Kogan

National Drought Mitigation Center: Faculty Publications

Drought is a normal, recurring feature of climate throughout the world, with characteristics and impacts that can vary from region to region. Figure 1.1 illustrates the regular occurrence of drought within the United States between 1895 and 2010 with approximately 14% of the country, on average (plotted by black dotted line), experiencing severe to extreme drought conditions during any given year. Drought conditions can persist in a region for several years, as occurred in the United States in the 1930s, 1950s, and early 2000s, and tree ring and other proxy records confirm that multiple-year droughts are part of the long-term …

Investigation Of Arsenic In The Transition Zone Basin Of The Mojave River, Matthew Edward Howard

Theses Digitization Project

The purpose of this project was to identify the source(s) of arsenic in the Transition Zone subbasin of the Mojave River. The transition zone is a sub-section of the Mojave River watershed. The project area is located in the arid southwestern desert region of the United States. 43 monitoring wells were sampled during September of 2010 and October of 2011. The objective of this project is to understand the processes by which arsenic is being released from sediment into groundwater supply. This project is part of an ongoing study of Transition Zone subbasin and will be used in future work …

Interannual And Spatial Impacts Of Phenological Transitions, Growing Season Length, And Spring And Autumn Temperatures On Carbon Sequestration: A North America Flux Data Synthesis, Chaoyang Wu, Alemu Gonsamo, Jing Ming Chen, Werner A. Kurz, David T. Price, Peter M. Lafleur, Rachhpal S. Jassal, Danilo Dragoni, Gil Bohrer, Christopher M. Gough, Shashi B. Verma, Andrew E. Suyker, J. William Munger

School of Natural Resources: Faculty Publications

Understanding feedbacks of ecosystem carbon sequestration to climate change is an urgent step in developing future ecosystem models. Using 187 site-years of flux data observed at 24 sites covering three plant functional types (i.e. evergreen forests (EF), deciduous forests (DF) and non-forest ecosystems (NF) (e.g., crop, grassland, wetland)) in North America, we present an analysis of both interannual and spatial relationships between annual net ecosystem production (NEP) and phenological indicators, including the flux-based carbon uptake period (CUP) and its transitions, degree-day-derived growing season length (GSL), and spring and autumn temperatures. Diverse responses were acquired between annul NEP and these indicators …

A Five-Year Analysis Of Carbon Stock Plots In The Gordon Natural Area’S Big Woods, Cathy Spahr, Chad Hudson, Andy Tamez

Forest Carbon Storage Study Documents

No abstract provided.

A Synoptic Perspective Of The Record 1-2 May 2010 Mid-South Heavy Precipitation Event, Joshua D. Durkee, Lee Campbell, Kyle Berry, Dustin Jordan, Gregory Goodrich, Rezaul Mahmood, Stuart Foster

High Plains Regional Climate Center: Staff Publications

During 1–2 May 2010, a series of strong thunderstorms led to 41, 57, and 43 tornado, severe wind, and severe hail reports, respectively, across portions of the southern United States. In addition to severe weather, these storms also distributed recordsetting rainfall amounts across the mid-South region, which contributed to historic flooding across portions of central and western Kentucky and Tennessee (Fig. 1). This heavy precipitation event was sampled by multiple surface observational networks, including (but not limited to) 48 research-grade automated stations from the Kentucky Mesonet (www.kymesonet .org), first-order automated stations from the National Weather Service (NWS; www.ncdc.noaa.gov /oa/ncdc.html), and …

Holocene House Hunting: An Application Of Satellite Image Analysis Towards Locating Prehistoric Archeological Sites In Alaska's Brooks Range, Joseph Keeney

Undergraduate Honors Theses

In this study, satellite image analysis was applied to archeological sites at Lake Matcharak in the Brooks Range of Alaska. The Goal was to test whether or not satellite remote sensing, which has been successful in locating large-size archeological features, could be applied to small-size prehistoric features found in Arctic Alaska. Using 1-m resolution IKONOS and 30-m resolution ASTER DEM data, vegetation indices (NDVI and tasseled cap) and slope were generated and stacked into one image. Supervised and unsupervised classifications were then applied to the resulting image to look for spectral/slope characteristics that were unique to known site locations at …

Drought Drove Forest Decline And Dune Building In Eastern Upper Michigan, Usa, As The Upper Great Lakes Became Closed Basins, Walter L. Loope, Henry M. Loope, Ronald J. Goble, Timothy G. Fisher, David E. Lytle, Robert J. Legg, Douglas A. Wysocki, Paul R. Hanson, Aaron R. Young

Department of Earth and Atmospheric Sciences: Faculty Publications

Current models of landscape response to Holocene climate change in midcontinent North America largely reconcile Earth orbital and atmospheric climate forcing with pollen-based forest histories on the east and eolian chronologies in Great Plains grasslands on the west. However, thousands of sand dunes spread across 12,000 km² in eastern upper Michigan (EUM), more than 500 km east of the present forest-prairie ecotone, present a challenge to such models. We use 65 optically stimulated luminescence (OSL) ages on quartz sand deposited in silt caps (n = 8) and dunes (n = 57) to document eolian activity in EUM. Dune building …

Bacterial Diversity In Biological Soil Crusts From Extrazonal Mountain Dry Steppes In Northern Mongolia, Anne Kemmling, Birgit Pfeiffer, Rolf Daniel, Michael Hoppert

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Biological Soil Crusts (BSCs), consisting of prokaryotes, microalgae, lichens, mosses and eventually small vascular plants, cover wide areas in arid and semi-arid environments. In the present study, the microbial diversity of these crusts was explored at extrazonal mountain steppe sites in the western Khentej (Northern Mongolia). At the study site the Siberian taiga borders on the Mongolian-Daurian forest steppe, resulting in a unique intermixture of the dark taiga, the light taiga, and forest steppe (DULAMSUREN 2004). Due to the presence of boreal, temperate and dauric elements the forest steppe is eminently rich in species (MÜHLENBERG et al. 2004).

BSCs in …

A Diatom Record Of Late Pliocene Cooling From The Ross Sea Continental Shelf, And-1b, Antarctica, Charlotte Sjunneskog, Diane Winter

ANDRILL Research and Publications

A late Pliocene – early Pleistocene, 2.9–2.0Ma, diatom record from the Antarctic Geological Drilling Program (ANDRILL) MIS drillcore AND-1B is presented. This core, recovered from beneath the Ross Ice Shelf south of Ross Island, comprises multiple diatomaceous-sediment units deposited during interglacial periods with open water over the core site. These represent interglacial phases of orbitally paced climate cycles and are punctuated by glacial advances. Extant diatom assemblages have limited presence in the late Pliocene record, which makes environmental interpretation less straight forward. We employ modern ecological data in combination with late Pliocene to present variation in diatom assemblages across the …

Kinematics And Basin Formation Along The Ezinepazar-Sungurlu Fault Zone, Ne Anatolia, Turkey, Mehmet Korhan Erturaç, Okan Tüysüz

Turkish Journal of Earth Sciences

The Ezinepazar-Sungurlu Fault (EzSF) is a major offshoot of the dextral North Anatolian Fault (NAF) zone, which bifurcates from the main fault strand around the Niksar pull-apart basin (37°E) and strikes through the Central Anatolian Block for 200 km to the west (34°E). The easternmost segment of the EzSF, the Ezinepazar Fault (EzF), which ruptured during the 1939 Erzincan earthquake (Mw= 7.8), has a very remarkable expression as a single-strand fault. Micromammal dating of young sediments along this segment indicate that the EzF was initiated during the Middle Pleistocene (0.7-1 Ma) and propagated westward accumulating 6.5±0.5 km maximum morphological offset. …

Varying Sediment Sources (Hudson Strait, Cumberland Sound, Baffin Bay) To The Nw Labrador Sea Slope Between And During Heinrich Events 0 To 4, J. T. Andrews, Donald C. Barber, A. E. Jennings, D. D. Erbel, B. Maclean, M. E. Kirby, J. S. Stoner

Geology Faculty Research and Scholarship

Core HU97048-007PC was recovered from the continental Labrador Sea slope at a water depth of 945m, 250km seaward from the mouth of Cumberland Sound, and 400km north of Hudson Strait. Cumberland Sound is a structural trough partly floored by Cretaceous mudstones and Paleozoic carbonates. The record extends from ~ 10 to 58k cal a BP. On-board logging revealed a complex series of lithofacies, including buff-colored detrital carbonate-rich sediments [Heinrich (H)-events] frequently bracketed by black facies. We investigate the provenance of these facies using quantitative X-ray diffraction on drill-core samples from Paleozoic and Cretaceous bedrock from the SE Baffin Island Shelf, …

Limnoarchaeology Using Commercially Available Side Scan Sonar: The Locks Of The Muscle Shoals Canal, Alabama, Robert Kavanaugh

Geography

This research aims to introduce, utilize and analyze commercially available side-scan sonar units as a viable scientific research tool in the interest of historic preservation and archaeological inventory of submerged structures and landscapes using a case study of the Muscle Shoals Canal in Alabama. Opened in November 1890, the nine locks of the Muscle Shoals Canal allowed traffic on the Tennessee River to circumvent the treacherous "Muscle Shoals", an achievement that replaced an abandoned attempt from over a half century earlier. The canal would continue operations until April 1918, when construction of Wilson Dam blocked river traffic through the canal. …

A New Late Holocene Eolianite Record From Altınkum Beach, North Cyprus, Ahmet Evren Ergi̇nal, Nafi̇ye Güneç Kiyak, Topçu Ahmet Ertek

Turkish Journal of Earth Sciences

In this study, we investigated the main depositional characteristics and obtained Optically Stimulated Luminescence (OSL) ages of coastal eolianite on the north coast of Cyprus, where this occurrence had not previously been recorded. Based on EDX/SEM and XRD data and field observations, the studied eolianite that crops out between elevations of 1 m and 14 m a.s.l. is made up predominantly of quartz grains, most of which consist of medium- to fine-grained sand. The rock comprises aragonite, calcite and quartz with lesser amounts of bornite and hematite as accessory minerals. OSL ages indicated that the initial deposition of eolianite sands …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopologues: 1. Comparison Between Models And Observations, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Debra Wunch, Vanessa Sherlock, Nicholas Deutscher, David Griffith, Paul O. Wennberg, Kimberly Strong, Dan Smale, Emmanuel Mahieu, Sabine Barthlott, Frank Hase, Omaira García, Justus Notholt, Thorsten Warneke, Geoffrey Toon, David Sayres, Sandrine Bony, Jeonghoon Lee, Derek Brown, Ryu Uemura, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

The goal of this study is to determine how H₂O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H₂O characteristics that are robust across data sets and that can be used to evaluate …

Limnoarchaeology Using Commercially Available Side Scan Sonar: The Locks Of The Muscle Shoals Canal, Alabama, Robert Kavanaugh

Theses

No abstract provided.

Trap Efficiency Of A Silted Prairie Reservoir: Rapidan Reservoir, Blue Earth County, Minnesota, Katherine Brosch Rassmussen

All Graduate Theses, Dissertations, and Other Capstone Projects

Rapidan Dam and Reservoir are located along the Blue Earth River south of Mankato, Minnesota. The dam was constructed in 1911 as a source of hydroelectric power to supplement the surroundings communities. Currently, the reservoir is heavily silted and provides little hydroelectric benefit while proving costly to maintain. This study (1) defines the sedimentary, geomorphic, stream flow and suspended load characteristics of the reservoir for 2008-2009 and (2) compares these parameters with those available from 1985 (23 years prior). Stream gauging and sediment sampling took place in 2008 and 2009 at three monitoring locations (two upstream and one downstream of …

Chromite-Hosted Silicate Melt Inclusions From Basalts In The Stravaj Complex, Southern Mirdita Ophiolite Belt (Albania), Izabella Havancsàk, Friedrich Koller, Jànos Kodolànyi, Csaba Szabò, Volker Höck, Kujtim Onuzi

Turkish Journal of Earth Sciences

The Stravaj ophiolite compex, part of the western Mirdita ophiolite belt in Albania, is located east of the Shpati massif, and west of the Shebenik massif. The Stravaj ophiolite sequence itself consist of MOR-related and subduction-related volcanic rocks (Hoeck et al. 2007) formed by pillow lavas and various dykes. The deeper units are formed by gabbros and plagioclase-bearing peridotites. The pillow lavas are intersected by basaltic dykes with a rather primitive composition. The studied basaltic dyke contains former relics of olivine, fresh spinel and clinopyroxene phenocrysts in a glassy groundmass. The silicate phases are strongly altered. The spinels appear as …

Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl

Turkish Journal of Earth Sciences

To provide quantitative palaeoclimate estimates based on different palaeobotanical techniques for three contemporaneous Pliocene leaf floras, we applied the Coexistence Approach (CoA), leaf margin analysis (LMA), the Climate Leaf Analysis Multivariate Program (CLAMP) and the European Leaf Physiognomic Approach (ELPA). Furthermore, we compared recently published estimates from an additional locality with our data. The leaf physiognomic techniques yield lower mean annual temperatures than the CoA, which is most likely caused by taphonomic biases. Due to these potential biases we are in favour of the CoA as the most reliable method, and its palaeotemperature estimates show similar temperatures for all localities. …

Growth Of Extensional Faults And Folds During Deposition Of An Evaporite-Dominated Half-Graben Basin; The Carboniferous Billefjorden Trough, Svalbard, Alvar Braathen, Karoline Bælum, Harmon Maher Jr., Simon J. Buckley

Geography and Geology Faculty Publications

Normal-sense movements along two major strands of the Billefjorden Fault Zone controlled sedimentation in the Carboniferous Billefjorden Trough. The Billefjorden Trough is a more than 2000 meters thick, west-dipping half-graben basin where accommodation was provided by combinations of extensional faulting and folding throughout the basin history. Whereas previous workers have interpreted several of these folds as due to Tertiary contraction, we argue that they developed during rifting, as extensional forced folds in the style described by other workers from rifts such as the Gulf of Suez. The present basin geometry indicates that accommodation was facilitated by a combination of fault …

Assessment Of Climate Change Effect On Water Harvesting Structures In Rainfed Regions: Geospatial Data Mining Approach, Sreedhar Nallan, Leisa Armstrong

Research outputs 2012

Advances in the Information and Technologies (ICT) may assist researchers in the assessment of watershed development programmes by developing better visualization understanding of their impacts. GIS based research studies utilizing remote sensing images can facilitate in identifying the potential zones for watershed development and enable improved ground water resources. Effective watershed management is dependent on a number of factors such as demography, climate, soil, land use and topography and these are affected by changing climatic conditions. For example, changes in rainfall intensity and volume in rain fed areas can influence the effectiveness of the placement of watershed structures. Existing methods …

Holocene Arroyo Cut And Fills Cycles, South-Central Washington, Matthew Ian Durkee

All Master's Theses

Ephemeral streams have cut deeply incised arroyos into alluvial and eolian sediments in many of the watersheds within the Yakima Training Center (YTC) military reservation, south-central Washington. The most recent channel incision episode along Selah Creek is primarily attributed to multiple failures of an irrigation reservoir dam during the winters of 1909 and 1910. The modern arroyo exposed evidence of at least one previous episode of arroyo incision to a depth of ~4 m that occurred just prior to 1530- 1340 cal yr BP. Filling of this paleo-arroyo with fine to coarse grained sand ceased between 650-103 cal yr BP. …

Applying Gis Metrics To Determine Degree Of Glacial Modification In Mountainous Landscapes, Carl Delbert Swanson Ii

All Master's Theses

The ability to quantitatively assess the degree of glaciation in mountainous areas can be a powerful tool in unraveling the evolution of landscapes, and provide key insights in regions where field research is difficult. Here we determine, test, and apply metrics that assess the relative degree of past glacial modification in mountainous landscapes. Results show that slope results can be used to quantitatively assess the degree to which an area is modified by glaciation. In particular, analysis of basins using slope frequency distribution curves and slope vs. elevation plots capture steeper slopes, flatter valley bottoms, cirques, and arêtes of glaciated …

Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, F. Benjamin Zhan, T. Edwin Chow, Jeff Gaines Wilson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Background: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005.

Methods: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality …

Hydraulic Conductivity Of The High Plains Aquifer Re-Evaluated Using Surface Drainage Patterns, Wei Luo, Darryll T. Pederson

Department of Earth and Atmospheric Sciences: Faculty Publications

The High Plains Aquifer (HPA), underlying parts of 8 states from South Dakota to Texas, is one of the largest fresh water aquifers in the world and accounts for 30% of the groundwater used for irrigation in the US. Determining the distribution of HPA’s hydraulic conductivity (K) is critical for water management and addressing water quality issues. K is traditionally estimated from well pumping data coupled with computer modeling and is known to be highly variable, spanning several orders of magnitude for the same type of rock. Here we show that applying our innovative method of determining effective …