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The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack

Chemistry & Biochemistry Faculty Publications

Seepage of coal-bed methane (CBM) through soils is a potential source of atmospheric CH₄ and also a likely source of ancient (i.e. ¹⁴C-dead) carbon to soil microbial communities. Natural abundance ¹³C and ¹⁴C compositions of bacterial membrane phospholipid fatty acids (PLFAs) and soil gas CO₂ and CH₄ were used to assess the incorporation of CBM-derived carbon into methanotrophs and other members of the soil microbial community. Concentrations of type I and type II methanotroph PLFA biomarkers (16:1ω8c and 18:1ω8c, respectively) were elevated in CBM-impacted soils compared with a control site. Comparison …

Tragulidae (Artiodactyla, Ruminantia) From The Middle Miocene Chinji Formation Of Pakistan, Muhammad Akbar Khan, Muhammad Akhtar

Turkish Journal of Earth Sciences

The fossil record of the Siwalik tragulids remains poorly documented. The study of the tragulid material from the Chinji Formation allows the identification of 3 species: Dorcatherium minus, Dorcatherium majus and Dorcabune anthracotherioides. The tragulid assemblage is quite rich and Dorcatherium is the predominant taxon in the Chinji Formation of Pakistan. The fossils from the Chinji Formation of the Chakwal district, northern Pakistan, may document the first appearance of the 3 tragulid species in the Lower Siwaliks. The selenodonty and palaeoecology of the Siwalik tragulids are also discussed.

Multi-Proxy Evidences Of Mid-Pleistocene Dry Climates Observed On Calcretes In Central Turkey, Ceren Küçükuysal, Asuman Günal Türkmenoğlu, Seli̇m Kapur

Turkish Journal of Earth Sciences

Palaeosols are very important in reconstructing palaeoclimate studies, since they are accepted as useful climate markers and as potential providers of proxy data. The study of the palaeosols of the Plio-Pleistocene rock sequences around Ankara revealed evidence for a reconstruction of the Quaternary palaeoclimate of the region. The study area is located in Bala, south-east of Ankara, which contains Middle Pleistocene red palaeosols with powdery to nodular calcrete developments, alternating with channel deposits. During this warm and arid period in the Pleistocene, the limited water available in the soil led to the accumulation of low magnesian carbonates, forming calcretes. The …

Applying Dc Resistivity Imaging To Investigating The Relationship Between Water Quality And Transpiration Beneath Circular Islands In The Okavango Delta, Botswana: A Case Study Of Thata Island, E. M. Shemang, L. N. Molwalefhe, Kevin L. Mickus

College of Natural and Applied Sciences

An electrical resistivity survey was carried out on Thata Island, one of the numerous circular islands in the Okavango Delta, to investigate the mechanism governing interactions between surface water, vegetation and groundwater. Seven data profiles were collected across the island and modelling results indicated that the centre of the island had low resistivity values (less than 10 ohm-m), while resistivity values increased laterally outside the island. Such lateral resistivity zoning responded to variation in shallow groundwater chemistry below the islands having a high concentration of solutes inside and the presence of fresh water outside the islands. Borehole to surface resistivity …

Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif

Browse all Theses and Dissertations

A stromatolite is a laminated benthic microbial deposit. Its uniqueness arises from being present since the Precambrian to the present. Stromatolites recorded a peak time during the Mesoproterozoic, subsequently they witnessed abrupt rises and falls in abundance with the steepest decline in the Ordovician period, from which it never recovered from. There is no consensus yet regarding the reasons behind the decline of stromatolites. Thus the decline of these microbial deposits remains an enigma. Additionally, a literature gap exists regarding the reasons that specifically led to the Ordovician decline. Accordingly, the focus of this literature-based MSc. thesis is to find …

Appropriate Terminology For Karst-Like Phenomena: The Problem With ‘Pseudokarst’, Rolan S. Eberhard, Chris Sharples

International Journal of Speleology

The practice of referring to certain morphologically karst-like phenomena as ‘pseudokarst’ is problematic, because it ignores basic principles of sound classification, logical naming conventions and accepted geomorphic classifications and terminology. These problems have compounded the difficulty in establishing an accepted classification of ‘pseudokarst’ types. The practice embodies a karst-centric perspective which should be avoided in favour of using conventional geomorphic terminology for non-karstic features. We illustrate this by providing existing conventional terms for many ‘pseudokarst’ types reported in the literature.

Predictive Models For Escherichia Coli Concentrations At Inland Lake Beaches And Relationship Of Model Variables To Pathogen Detection, Donna S. Francy, Erin A. Stelzer, Joseph W. Duris, Amie M. G. Brady, John H. Harrison, Heather E. Johnson, Michael W. Ware

United States Geological Survey: Staff Publications

Predictive models, based on environmental and water quality variables, have been used to improve the timeliness and accuracy of recreational water quality assessments, but their effectiveness has not been studied in inland waters. Sampling at eight inland recreational lakes in Ohio was done in order to investigate using predictive models for Escherichia coli and to understand the links between E. coli concentrations, predictive variables, and pathogens. Based upon results from 21 beach sites, models were developed for 13 sites, and the most predictive variables were rainfall, wind direction and speed, turbidity, and water temperature. Models were not developed at sites …

Chronology And Provenance Of Last-Glacial (Peoria) Loess In Western Iowa And Paleoclimatic Implications, Daniel R. Muhs, E. Arthur Bettis Iii, Helen M. Roberts, Stephen S. Harlan, James B. Paces, Richard L. Reynolds

United States Geological Survey: Staff Publications

Geologic archives show that the Earth was dustier during the last glacial period. One model suggests that increased gustiness (stronger, more frequent winds) enhanced dustiness. We tested this at Loveland, Iowa, one of the thickest deposits of last-glacial-age (Peoria) loess in the world. Based on K/Rb and Ba/Rb, loess was derived not only from glaciogenic sources of the Missouri River, but also distal loess from non-glacial sources in Nebraska. Optically stimulated luminescence (OSL) ages provide the first detailed chronology of Peoria Loess at Loveland. Deposition began after ~27 ka and continued until ~17 ka. OSL ages also indicate that mass …

Origin Of The Sinai-Negev Erg, Egypt And Israel: Mineralogical And Geochemical Evidence For The Importance Of The Nile And Sea Level History, Daniel R. Muhs, Joel Roskin, Haim Tsoar, Gary Skipp, James Budahn, Amihai Sneh, Naomi Porat, Jean-Daniel Stanley, Itzhak Katra, Dan G. Blumberg

United States Geological Survey: Staff Publications

The Sinai-Negev erg occupies an area of 13,000 km² in the deserts of Egypt and Israel. Aeolian sand of this erg has been proposed to be derived from the Nile Delta, but empirical data supporting this view are lacking. An alternative source sediment is sand from the large Wadi El Arish drainage system in central and northern Sinai. Mineralogy of the Negev and Sinai dunes shows that they are high in quartz, with much smaller amounts of K-feldspar and plagioclase. Both Nile Delta sands and Sinai wadi sands, upstream of the dunes, also have high amounts of quartz relative …

A Global Standard For Monitoring Coastal Wetland Vulnerability To Accelerated Sea-Level Rise, Edward L. Webb, Daniel A. Friess, Ken W. Krauss, Donald R. Cahoon, Glenn R. Guntenspergen, Jacob Phelps

United States Geological Survey: Staff Publications

Sea-level rise threatens coastal salt-marshes and mangrove forests around the world, and a key determinant of coastal wetland vulnerability is whether its surface elevation can keep pace with rising sea level. Globally, a large data gap exists because wetland surface and shallow subsurface processes remain unaccounted for by traditional vulnerability assessments using tide gauges. Moreover, those processes vary substantially across wetlands, so modelling platforms require relevant local data. The low-cost, simple, high-precision rod surface-elevation table–marker horizon (RSET-MH) method fills this critical data gap, can be paired with spatial data sets and modelling and is financially and technically accessible to every …

The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs

United States Geological Survey: Staff Publications

Study of geologic records of dust composition, sources and deposition rates is important for understanding the role of dust in the overall planetary radiation balance, fertilization of organisms in the world’s oceans, nutrient additions to the terrestrial biosphere and soils, and for paleoclimatic reconstructions. Both glacial and non-glacial processes produce fine-grained particles that can be transported by the wind. Geologic records of dust flux occur in a number of depositional archives for sediments: (1) loess deposits; (2) lake sediments; (3) soils; (4) deep-ocean basins; and (5) ice sheets and smaller glaciers. These archives have several characteristics that make them highly …

Putting Local Knowledge And Context To Work For Gunnison Sage-Grouse Conservation, Corrine Noel Knapp, James Cochran, F. Stuart Chapin Iii, Gary Kofinas, Nathan Sayre

Human–Wildlife Interactions

Successful conservation requires adequate understanding of focal species and ecology, practices that may assist species survival, and a community of people willing and able to conserve the species. For many species at risk, we operate with imperfect knowledge in complex conservation contexts. In this case study involving the Gunnison sage-grouse (Centrocercus minimus), we interviewed 26 community-defined local experts, including both those with and without related academic degrees, to assess the utility of local knowledge for understanding and informing conservation opportunities.This project suggests several benefits of integrating local knowledge that apply specifically to rare and endemic populations, including the …

Vitals Rates And Seasonal Movements Of Two Isolated Greater Sage-Grouse Populations In Utah's West Desert, Jason D. Robinson, Terry A. Messmer

Human–Wildlife Interactions

Declines in greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) populations in Utah over the last century parallel range-wide trends. However, little is known about the ecology of sage-grouse populations that inhabit Utah’s naturally fragmented habitats. Utah’s West Desert sage-grouse populations occupy sagebrush (Artemisia spp.) habitats that are geographically separated by the Great Salt Lake, and largely confined to the Sheeprock and Deep Creek watersheds. From 2005 to 2006, we monitored sage-grouse that were radio-collared in each watershed to determine the factors affecting the vital rates in these isolated populations. Livestock grazing by domestic cattle was the dominate land use, …

Seismic Reflection Exploration Of Geothermal Reservoir Atnaval Air Station (Nas) Fallon, Nevada, Alay Ghebremariam Gebregiorgis

Open Access Theses & Dissertations

The Primary objective of this study is to increase geologic and tectonic understanding of the geothermal resources at the Naval Air Station (NAS) Fallon, Nevada. The seismic reflection method is employed to study faults, fractures and other tectonic structures in the subsurface in order to identify geothermal drill targets. The efficiency of geothermal systems is strongly dependent on water circulation. Discrete faults may be permeable and provide pathways for water flow depending on the fracture density. It is therefore desirable to detect and map faults and fracture zones and characterize their physical properties when evaluating a geothermal prospect.

The seismic …

Are 34s-Enriched Authigenic Sulfide Minerals A Proxy For Elevated Methane Flux And Gas Hydrates In The Geologic Record?, Walter S. Borowski, Nancy M. Rodriguez, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

The sulfate–methane transition (SMT) zone is a diagenetic transition within anoxic marine sediments created by the metabolic activity of a consortium of sulfate-reducing bacteria and methane-oxidizing Archaea. As interstitial dissolved sulfate is consumed by microbially mediated sulfate reduction of sedimentary organic matter (SOM) and anaerobic oxidation of methane (AOM) large enrichments of ³⁴S occur in the interstitial sulfate pool. These isotopic enrichments are transmitted to the dissolved sulfide pool (∑HS⁻) and subsequently into sulfide minerals (So, ∼FeS, FeS₂).

We investigate the sulfur isotopic composition of pore-water sulfate and sulfide minerals at three sites underlain …

Microbially Induced Sedimentary Structures Recording An Ancient Ecosystem In The Ca. 3.48 Billion-Year-Old Dresser Formation, Pilbara, Western Australia, Nora Noffke, Daniel Christian, David Wacey, Robert M. Hazen

OES Faculty Publications

Microbially induced sedimentary structures (MISS) result from the response of microbial mats to physical sediment dynamics. MISS are cosmopolitan and found in many modern environments, including shelves, tidal flats, lagoons, riverine shores, lakes, interdune areas, and sabkhas. The structures record highly diverse communities of microbial mats and have been reported from numerous intervals in the geological record up to 3.2 billion years (Ga) old. This contribution describes a suite of MISS from some of the oldest well-preserved sedimentary rocks in the geological record, the early Archean (ca. 3.48 Ga) Dresser Formation, Western Australia. Outcrop mapping at the meter to …

Evolution Of High Tooth Replacement Rates In Sauropod Dinosaurs, Michael D. D'Emic, John A. Whitlock, Kathlyn M. Smith, Daniel C. Fisher, Jeffrey A. Wilson

Earth, Environment & Sustainability: Faculty Publications

Background: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates.

Methodology/Principal Findings: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined …

Full Issue 42(2)

International Journal of Speleology

All articles in Volume 42 Issue 2. Does not include cover image.

Do Cryoconite Holes Have The Potential To Be Significant Sources Of C, N, And P To Downstream Depauperate Ecosystems Of Taylor Valley, Antarctica?, Elizabeth A. Bagshaw, Martyn Tranter, Andrew G. Fountain, Kathleen A. Welch, Hassan J. Basagic, W. Berry Lyons

Geology Faculty Publications and Presentations

Nutrient recycling occurs in hydrologically isolated cryoconite holes on the glaciers of the McMurdo Dry Valleys, Antarctica. Biogeochemical processes enrich the cryoconite holes with solute and nutrients compared to the source sediment and glacier ice. The position of the glacier within the landscape affects the physical and biogeochemical character of the cryoconite holes, with those found in more biologically productive areas of the valley having higher concentrations of C, N, and P and higher pH. Comprehensive assessment of the quality and quantity of bioavailable C, N, and P shows that the cryoconite holes represent a significant store of nutrient in …

The Use Of Passive Seismological Imaging In Speleogenetic Studies; An Example From Kanaan Cave, Lebanon, Carole Nehme, Christophe Voisin, Armand Mariscal, Pierre-Charles Gérard, Cécile Cornou, Badr Jabbour-Gédéon, Samer Amhaz, Nancy Salloum, Nada Badaro-Saliba, Jocelyne Adjizian-Gérard, Jean-Jacques Delannoy

International Journal of Speleology

Among many parameters that control the evolution of caves stands the volume of unconsolidated clay sediments generally produced by the alteration of the calcareous rocks. Here we introduce the use of a passive seismological imaging technique to investigate the clay deposits and estimate its total volume in a cave. Applied for the first time for speleogenesis studies, the HVSR (Horizontal / Vertical Spectral Ration) is a geophysical technique that can help better interpret cave geomorphology. We apply seismological spectral techniques (H/V ratio) on ambient noise vibrations to derive the clay volume, as well as its shape. This technique applied on …

A Model For The Formation Of Layered Soda-Straw Stalactites, Bence Paul, Russell Drysdale, Helen Green, Jon Woodhead, John Hellstrom, Rolan Eberhard

International Journal of Speleology

Climate records based upon instrumental data such as rainfall measurements are usually only available for approximately the last 150 years at most. To fully investigate decadal-scale climate variation, however, these records must be extended by the use of climate proxies. Soda-straw stalactites (straws) are a previously under-utilised potential source of such data. In this contribution we investigate the structure and formation of straws and look at some issues that may affect the reliability of straw-based palaeoclimate records. We use laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) trace element analysis to document surface contamination features that have the potential to obscure annual …

Layer-Bounding Surfaces In Stalagmites As Keys To Better Paleoclimatological Histories And Chronologies, Loren Bruce Railsback, Pete D. Akers, Lixin Wang, Genevieve A. Holdridge, Ny Riavo Voarintsoa

International Journal of Speleology

Petrographic recognition of layer-bounding surfaces in stalagmites offers an important tool in constructing paleoclimate records. Previous petrographic efforts have examined thickness of layers (a possible proxy for annual rainfall) and alternation of layers in couplets (a possible indicator of seasonality). Layer-bounding surfaces, in contrast, delimit series of layers and represent periods of non-deposition, either because of exceptionally wet or exceptionally dry conditions.

Two types of layer-bounding surfaces can be recognized according to explicitly defined petrographic criteria. Type E layer-bounding surfaces are surfaces at which layers have been truncated or eroded at the crest of a stalagmite. Keys to their recognition …

Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities.

Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such …

Combating Forced Labour And Human Trafficking In Africa: The Role Of Endogenous And Exogenous Forces, Ambe J. Njoh, Elizabeth N.M. Ayuk-Etang

School of Geosciences Faculty and Staff Publications

It is widely believed that indigenous culture and tradition are at the root of the human trafficking and forced labour problem in Africa. Adherents to this viewpoint also claim that endogenous as opposed to exogenous forces impede efforts to eradicate the problem. This study employed a loglinear regression model to test the tenability of this claim. It hypothesized an inverse association between indigenous culture/tradition and efforts to combat human trafficking. The hypothesis was rejected. It is shown that anti-trafficking initiatives are less successful where indigenous tradition is dominated, or has been usurped, by imported cultural practices.

An Estimate Of Groundwater Recharge In The Nabogo River Basin, Ghana Using Water Table Fluctuation Method And Chloride Mass Balance, Melanie Lynn Krautstrunk

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Cambrian-Precambrian fractured sandstone aquifer in the Nabogo River Basin in the Sahelian Northern Region in Ghana is one of the most important sources for fresh water supply for the local rural communities there. Recent population growth and commercial agricultural interests in this region could have an impact on this critical water resource. Groundwater recharge estimates are determined in this study using the Water Table Fluctuation Method and Chloride Mass Balance and can be applied to future sustainability studies of the region's water resources. Recharge estimates of the Water Table Fluctuation Method are in a range of 10-143 mm/yr or …

Integrated Approach For Hydrogeologic Investigations In Africa: Inferences From Space-Borne And Land-Based Gravity, Aeromagnetic, Gis, And Remote Sensing Data, Mohamed El Sayed Ahmed Ahmed

Dissertations

An integrated (space-borne and land-based gravity, aeromagnetic, GIS, and remote sensing) approach was developed, tested, and applied to investigate the following on regional scales (Africa) or local scales (El Qaa Plain, Sinai): (1) assess the capability of GRACE data (04/2002 to 08/2011) for monitoring elements of hydrologic systems on the sub-basin level (Task 1); (2) address the nature and the controlling factors (e.g., climatic and/or human pressure-related) affecting the inter-annual GRACE-derived Terrestrial Water Storage (TWS) trends over a large suite of hydrologic systems and domains in (Africa) (Task 2); and (3) identify the structural, geologic and hydrologic settings as well …

Assessing The Impacts Of Surface Water Removal For Use In Natural Gas Extraction On A Watershed Level, Carrie Ann Davis

Graduate Theses and Dissertations

In this study, the Soil and Water Assessment Test (SWAT) was used as a tool to predict whether diffuse water removal from the Cadron Creek watershed for use with natural gas development would have an impact on downstream flow within the watershed. Cadron Creek watershed expands across four counties within Arkansas and is located in the Fayetteville Shale Gas region. This region is experiencing significant growth in natural gas development. Successful development of shale gas depends on the identification of what water supplies are available for production without interfering with community and environmental needs. The SWAT model used to evaluate …

Variability Of Pennsylvanian-Permian Carbonate Associations And Implications For Nw Pangea Palaeogeography, East-Central British Columbia, Canada, K. D. Zubin-Stathopoulos, B. Beauchamp, V. I. Davydov, C. M. Henderson

Geosciences Faculty Publications and Presentations

Different stages of Pennsylvanian-Permian carbonate sedimentation in east-central British Columbia record a complex history of changing environments influenced by evolving palaeogeography and climate. Newly recognized tectonically controlled features affected the distribution and variability of carbonate associations, providing new interpretations for this portion of the west coast of Pangea. Both a heterozoan (cool water) and photozoan (warm-water) association were identified on either side of a palaeogeographic high here informally termed “Tipinahokan Peninsula”. Cool water carbonates were located outboard, or to the west of this high, an area influenced by upwelling waters. Inboard of this high, a warm, protected sea developed, here …

Sigma Gamma Epsilon Undergraduate Research Poster Session, Erika Elswick

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Sigma Gamma Epsilon undergraduate research poster session will highlight recent and on-going student research. Abstracts for poster presentations will be available in the Geological Society of America Abstracts with Programs, 2012 Annual Meeting, Charlotte, North Carolina, 4-7 November 2012.

Geosciences Newsletter - 2012, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 5, No. 1

• Faculty Updates
• Faculty Updates
• Deanna Romanosky
• Publications
• MGRRE
• Alumni Award
• Gifts
• Grants
• Endowments