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2014

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Articles 841 - 870 of 1044

Full-Text Articles in Earth Sciences

Natural Phenomena As Potential Influence On Social And Political Behavior: The Earth’S Magnetic Field, Jackie R. East Jan 2014

Natural Phenomena As Potential Influence On Social And Political Behavior: The Earth’S Magnetic Field, Jackie R. East

Theses and Dissertations--Political Science

Researchers use natural phenomena in a number of disciplines to help explain human behavioral outcomes. Research regarding the potential effects of magnetic fields on animal and human behavior indicates that fields could influence outcomes of interest to social scientists. Tests so far have been limited in scope. This work is a preliminary evaluation of whether the earth’s magnetic field influences human behavior it examines the baseline relationship exhibited between geomagnetic readings and a host of social and political outcomes. The emphasis on breadth of topical coverage in these statistical trials, rather than on depth of development for any one model, …

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From Geology To Art History: Ceramist Alexandre Brongniart’S Overlooked Contribution To The Developing Science Of Art History In The Early Nineteenth Century, Julia A. Carr-Trebelhorn Jan 2014

From Geology To Art History: Ceramist Alexandre Brongniart’S Overlooked Contribution To The Developing Science Of Art History In The Early Nineteenth Century, Julia A. Carr-Trebelhorn

Theses and Dissertations--Art and Visual Studies

Alexandre Brongniart was known for his work as an important geologist and as an administrator at the Sèvres Porcelain Manufactory, but his roles as art historian and museologist are overlooked. Brongniart created a holistic methodology taken directly from science and applied it to ceramic art of all cultures and eras. He had a uniquely modern perspective on time, world culture, and archeology. Brongniart wrote about the art of Asia and the Americas on an equal status with that of the Classical West at least fifty years before it became a mainstream idea. Brongniart integrated scientific principle and practice into the …

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Monitoring The Influence Of Acid Deposition On Soil And Implications To Forest Health In The Daniel Boone National Forest, Tyler M. Sanderson Jan 2014

Monitoring The Influence Of Acid Deposition On Soil And Implications To Forest Health In The Daniel Boone National Forest, Tyler M. Sanderson

Theses and Dissertations--Forestry and Natural Resources

Combustion of fossil fuels has contributed to many environmental problems including acid deposition. The Clean Air Act (CAA) was created to reduce ecological problems by cutting emissions of sulfur and nitrogen. Reduced emissions and rainfall concentrations of acidic ions have been observed since the enactment of the CAA, but soils continue to receive some acid inputs. Soils sensitive to acid deposition have been found to have low pH, a loss of base cations and a shift in the mineral phase controlling the activity of Al3+ and/or SO42-. If inputs continue, soil may be depleted of base …

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Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu Jan 2014

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

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Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova Jan 2014

Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

A description of finite element model and analysis of a shell with an infill is performed. A large diameter thin cylindrical shell structure with the edge leaning against compressible foundation soil is analyzed. Different materials are considered individually for the models of each structure shell and infill component (metal or reinforced concrete shell, and granular or elastic infill in a shell and foundation soil loaded by the structure). Contact conditions between 1) the infill and the shell’s inner surface and 2) between the foundation material and the shell edge are analyzed. An example of calculating strain conditions in the shell …

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Assessing Optimal Set Of Implemental Physical Parameterization Schemes In A Multi-Physics Land Surface Model Using Genetic Algorithm, S. Hong, X. Yu, S. K. Park, Y.-S. Choi, Boksoon Myoung Jan 2014

Assessing Optimal Set Of Implemental Physical Parameterization Schemes In A Multi-Physics Land Surface Model Using Genetic Algorithm, S. Hong, X. Yu, S. K. Park, Y.-S. Choi, Boksoon Myoung

Mathematics, Physics, and Computer Science Faculty Articles and Research

Optimization of land surface models has been challenging due to the model complexity and uncertainty. In this study, we performed scheme-based model optimizations by designing a framework for coupling "the micro-genetic algorithm" (micro-GA) and "the Noah land surface model with multiple physics options" (Noah-MP). Micro-GA controls the scheme selections among eight different land surface parameterization categories, each containing 2–4 schemes, in Noah-MP in order to extract the optimal scheme combination that achieves the best skill score. This coupling framework was successfully applied to the optimizations of evapotranspiration and runoff simulations in terms of surface water balance over the Han River …

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Exploring The Hydrogeologic Controls On Brackish Water And Its Suitability For Use In Hydraulic Fracturing: The Dockum Aquifer, Midland Basin, Texas, Francisco Ruben Reyes Jan 2014

Exploring The Hydrogeologic Controls On Brackish Water And Its Suitability For Use In Hydraulic Fracturing: The Dockum Aquifer, Midland Basin, Texas, Francisco Ruben Reyes

Open Access Theses & Dissertations

Water scarcity in arid regions can limit or impede certain hydrocarbon production activities, such as hydraulic fracturing and well drilling. The Midland Basin, a major oil-producing area in semi-arid far west Texas and the eastern sub-basin of the Permian Basin, is already impacted by limited freshwater availability. A typical tight oil well in the Midland Basin requires ~3.8–11.4 × 103 m3 of water per fracture treatment (Nicot et al., 2012). Despite draught conditions and limited resources, data for 2011 indicate freshwater comprises ~70% of the water used in hydraulic fracturing in the Midland basin. Thus, the Midland Basin represents an …

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The Influences Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Allen, David E. Longer, Edward E. Gbur, Lichen Hao Jan 2014

The Influences Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Allen, David E. Longer, Edward E. Gbur, Lichen Hao

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Many row-crop fields today have declined in soil fertility due to poor management practices and overuse of pesticides. Under these conditions, plant nutrient uptake can be sub-optimal. There are several soil amendments that can be used to improve soil quality and plant growth. This study focused on the addition of biochar to the soil and the use of structured water to enhance plant growth. Biochar is produced by pyrolysis of organic feedstocks. Previous studies which focused on biochar have shown an increase in plant yield, nutrient availability in the soil, and soil water holding capacity. Structured water is the liquid …

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Calcite Dissolution Under Turbulent Flow Conditions: A Remaining Conundrum, Matthew D. Covington Jan 2014

Calcite Dissolution Under Turbulent Flow Conditions: A Remaining Conundrum, Matthew D. Covington

Geosciences Faculty Publications and Presentations

A significant body of experimental and theoretical work has examined the dissolution rates of calcite, and other carbonate minerals, under varying chemical and hydrodynamic conditions (see Morse & Arvidson (2002) for a comprehensive review). The relationships derived from this work have been applied extensively to the development of mechanistic models of speleogenesis (e.g. Dreybrodt 1996; Dreybrodt et al. 2005; Birk et al. 2005; Rehrl et al. 2008; Kaufmann 2009; Szymczak & Ladd 2011). However, the primary focus of these models has been on the early stages of cave formation, with less attention toward the later stages of cave evolution and …

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Eocene To Early Oligocene Turbidite Sedimentation In The Se Aegean (Karpathos Island, Se Greece): Stratigraphy, Facies Analysis, Nannofossil Study,And Possible Hydrocarbon Potential, George Pantopoulos, Avraam Zelilidis Jan 2014

Eocene To Early Oligocene Turbidite Sedimentation In The Se Aegean (Karpathos Island, Se Greece): Stratigraphy, Facies Analysis, Nannofossil Study,And Possible Hydrocarbon Potential, George Pantopoulos, Avraam Zelilidis

Turkish Journal of Earth Sciences

Paleogene turbidite deposits that outcrop at the SE Aegean (Karpathos Island, SE Greece) were investigated using sedimentological, biostratigraphical, and organic geochemical techniques. Results indicate that turbidite sedimentation in the area took place from the Early Eocene (NP12-14) to Late Eocene-Early Oligocene (NP20-21). Six different units were recognized in the turbidite succession based on sedimentological characteristics, outcropping in 2 major areas of the island (1 in the north and 1 in the south) and having a thickness of less than 1000 m. Deposition and spatial arrangement of sedimentary facies was affected by the already deformed carbonate substratum and changes in the …

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Source Of The Mineralizing Fluids In Ultramafic Related Magnesite In The Eskişehir Area, Northwest Turkey, Along The İzmir–Ankara Suture: A Stable Isotope Study, Asuman Kahya, Mustafa Kuşcu Jan 2014

Source Of The Mineralizing Fluids In Ultramafic Related Magnesite In The Eskişehir Area, Northwest Turkey, Along The İzmir–Ankara Suture: A Stable Isotope Study, Asuman Kahya, Mustafa Kuşcu

Turkish Journal of Earth Sciences

The Eskişehir magnesite deposits (Süleymaniye, Margı, and Tutluca) are located in the western part of the İzmir-Ankara Suture Zone, northwestern Turkey. These vein and stockwork type magnesite deposits, which occur along major and minor fault systems, are hosted by Alpine-type ultramafic rocks. The purpose of this study was to understand the origin of the hydrothermal waters responsible and the source of carbon dioxide, and to compare these deposits with similar magnesite occurrences in Turkey and elsewhere. Petrographic and XRD analyses indicate that magnesite was the major carbonate mineral formed. Deposits are predominantly micritic and locally microsparitic, but some also contain …

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Comparative Geochemical Study Of Soils Developed On Characteristic Black And Yellow Polymetallic Massive Sulfide Deposits In Eastern Pontides (Ne Turkey), Nezi̇hi̇ Köprübaşi, Emi̇n Çi̇ftçi̇, Sai̇t Cordan, Necla Köprübaşi, Cafer Özkul, Fatma Şi̇şman Tükel Jan 2014

Comparative Geochemical Study Of Soils Developed On Characteristic Black And Yellow Polymetallic Massive Sulfide Deposits In Eastern Pontides (Ne Turkey), Nezi̇hi̇ Köprübaşi, Emi̇n Çi̇ftçi̇, Sai̇t Cordan, Necla Köprübaşi, Cafer Özkul, Fatma Şi̇şman Tükel

Turkish Journal of Earth Sciences

The Harşit-Köprübaşı (Tirebolu) and Killik (Espiye) volcanogenic massive sulfide (VMS) deposits occur in the Eastern Pontide tectonic belt, one of the major tectonic units comprising Anatolia. They are hosted by Late Cretaceous dacitic to rhyolitic rocks overlain by thin layers of pelitic sediments. The region is considered as a metallogenic province since it is a host to numerous VMS deposits, mainly of the Kuroko type, with varying sizes and reserves and with fairly similar geochemical and mineralogical characteristics. In this study, 489 soil samples were systematically collected from both known mineralized sites and remote areas that have no indication of …

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Chemistry Of Magmatic And Alteration Minerals In The Chahfiruzeh Porphyry Copper Deposit, South Iran: Implications For The Evolution Of The Magmas And Physicochemical Conditions Of The Ore Fluids, Morteza Einali, Saeed Alirezaei, Federica Zaccarini Jan 2014

Chemistry Of Magmatic And Alteration Minerals In The Chahfiruzeh Porphyry Copper Deposit, South Iran: Implications For The Evolution Of The Magmas And Physicochemical Conditions Of The Ore Fluids, Morteza Einali, Saeed Alirezaei, Federica Zaccarini

Turkish Journal of Earth Sciences

The Chahfiruzeh deposit is a newly discovered porphyry-style copper deposit in the southern part of the Cenozoic Urumieh-Dokhtar magmatic arc of Iran. Mineralization is associated with a Miocene quartz-diorite to quartz-monzodiorite porphyritic intrusion (Chahfiruzeh porphyry) intruded into older basaltic and andesitic lava flows and pyroclastic rocks. Alteration assemblages and alteration zoning, typical of porphyry copper deposits, are well developed. Mineralization occurs in quartz-sulfide stockworks and as sulfide disseminations in the porphyritic intrusion and the immediate wall rocks. Pyrite and chalcopyrite are the main hypogene sulfide minerals; bornite and molybdenite are rare. Representative magmatic and alteration minerals, including plagioclase, amphibole, biotite, …

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Terebella Lapilloides Münster, 1833 From The Upper Jurassic-Lower Cretaceous İnaltı Carbonates, Northern Turkey: Its Taxonomic Position And Paleoenvironmental-Paleoecological Significance, Mustafa Yücel Kaya, Demi̇r Altiner Jan 2014

Terebella Lapilloides Münster, 1833 From The Upper Jurassic-Lower Cretaceous İnaltı Carbonates, Northern Turkey: Its Taxonomic Position And Paleoenvironmental-Paleoecological Significance, Mustafa Yücel Kaya, Demi̇r Altiner

Turkish Journal of Earth Sciences

The agglutinating annelid Terebella lapilloides Münster, 1833 is commonly encountered in reefal deposits from the Late Jurassic. This annelid is described and documented for the first time from the Upper Jurassic-Lower Cretaceous carbonates of the İnaltı Formation in the Central Pontides, Turkey. The whole İnaltı formation, 395 m in thickness, was studied near Bürnük village and 105 samples were collected along the section. The investigated thin sections reveal the shallow water and the reefal/fore-reefal character of the carbonates with coral-sponge frame-builders. The bioconstituents are accompanied by various microencrusters and microproblematica (such as Lithocodium aggregatum, Bacinella-type structures, Koskinobullina socialis, Radiomura cautica, …

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Reservoir Characterization Of The Burqan Formation Sandstone From Midyan Basin, Northwestern Saudi Arabia, Abdulaziz Al-Laboun, Abdurrahman Al-Quraishi, Haider Zaman, Mohammed Benaafi Jan 2014

Reservoir Characterization Of The Burqan Formation Sandstone From Midyan Basin, Northwestern Saudi Arabia, Abdulaziz Al-Laboun, Abdurrahman Al-Quraishi, Haider Zaman, Mohammed Benaafi

Turkish Journal of Earth Sciences

The Early Miocene sandstone of the Burqan Formation from Midyan Basin is considered an oil-bearing unit. The outcrops of this sandstone, which are exposed in the northwestern part of the basin, have been studied through field and laboratory-based investigations. During the field work, 81 surface samples were collected for reservoir characterization. Laboratory analyses were undertaken to determine the effect of the diagenesis on the reservoir quality using integrated sedimentological, petrological, and petrophysical analyses. According to these analyses, the sandstone of Burqan Formation is predominately subarkosic and sublitharenite in nature, medium to course grained in size, rounded to subangular in shape, …

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Development Of A Numerical 2-Dimensional Beach Evolution Model, Cüneyt Baykal Jan 2014

Development Of A Numerical 2-Dimensional Beach Evolution Model, Cüneyt Baykal

Turkish Journal of Earth Sciences

This paper presents the description of a 2-dimensional numerical model constructed for the simulation of beach evolution under the action of wind waves only over the arbitrary land and sea topographies around existing coastal structures and formations. The developed beach evolution numerical model is composed of 4 submodels: a nearshore spectral wave transformation model based on an energy balance equation including random wave breaking and diffraction terms to compute the nearshore wave characteristics, a nearshore wave-induced circulation model based on the nonlinear shallow water equations to compute the nearshore depth-averaged wave-induced current velocities and mean water level changes, a sediment …

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Testing Of The Recently Developed Tectonomagmatic Discrimination Diagrams From Hydrothermally Altered Igneous Rocks Of 7 Geothermal Fields, Kailasa Pandarinath Jan 2014

Testing Of The Recently Developed Tectonomagmatic Discrimination Diagrams From Hydrothermally Altered Igneous Rocks Of 7 Geothermal Fields, Kailasa Pandarinath

Turkish Journal of Earth Sciences

Recently developed multidimensional tectonomagmatic discrimination diagrams based on log-ratio variables of chemical elements, discordant outlier-free databases, and probability-based boundaries have been shown to work better than the earlier diagrams. Hydrothermally altered drilled well rock cuttings obtained from different depths of geothermal fields were used to test these diagrams to compare the inferred tectonic setting with the expected one. In spite of the hydrothermal alteration effects, these diagrams provided the following expected tectonic settings: (1) an arc setting for Ahuachapán and Berlin geothermal fields, El Salvador; (2) a rift setting for Cerro Prieto geothermal field, Mexico, and Tendaho geothermal field, Afar …

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Geology, Mineralogy, Geochemistry, And Depositional Environment Of A Late Miocene/Pliocene Fluviolacustrine Succession, Cappadocian Volcanic Province, Central Anatolia, Turkey, Ersel Göz, Selahatti̇n Kadi̇r, Ali̇ Gürel, Muhsi̇n Eren Jan 2014

Geology, Mineralogy, Geochemistry, And Depositional Environment Of A Late Miocene/Pliocene Fluviolacustrine Succession, Cappadocian Volcanic Province, Central Anatolia, Turkey, Ersel Göz, Selahatti̇n Kadi̇r, Ali̇ Gürel, Muhsi̇n Eren

Turkish Journal of Earth Sciences

This paper investigates the mineralogy, geochemistry, and depositional environment of Late Miocene/Pliocene fluviolacustrine deposits, including multiple ignimbrite levels and andesitic and basaltic lavas, within the Cappadocian Volcanic Province (CVP) of central Anatolia, Turkey. Palaeosols and calcretes formed within these terrestrial sedimentary rocks under near-surface or surface conditions. The palaeosols are composed predominantly of smectite ± illite with feldspar, quartz, calcite, opal-CT, and amphibole, and the calcretes mainly of calcite with minor feldspar, quartz, and accessory smectite ± palygorskite. The palygorskite occurs on and between the calcite crystals in the calcretes and at the edges of smectite flakes within the palaeosols, …

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Whole-Rock Geochemistry Of Basic And Intermediate Intrusive Rocks In The Ishiagu Area: Further Evidence Of Anorogenic Setting Of The Lower Benue Rift, Southeastern Nigeria, Anthony Chukwu, Smart Chika Obiora Jan 2014

Whole-Rock Geochemistry Of Basic And Intermediate Intrusive Rocks In The Ishiagu Area: Further Evidence Of Anorogenic Setting Of The Lower Benue Rift, Southeastern Nigeria, Anthony Chukwu, Smart Chika Obiora

Turkish Journal of Earth Sciences

Petrographic studies on the intrusive rocks from the Ishiagu area show that they are gabbro, dolerites, and diorite. The gabbro and diorite occur as stocks while the dolerites occur as sills in folded sedimentary sequence predominated by shale. Geochemical data confirmed the rocks as basic (gabbro and dolerites) and intermediate (diorite) rocks with silica contents ranging from 42.45 to 50.75 wt.% and 55.03 to 60.24 wt.%, respectively. They are predominantly alkaline (gabbro, dolerites, and diorites) with sparse tholeiites (few gabbro). The basic rocks are made up of calcic plagioclase (An_{49-54}), clinopyroxene, olivine (altered), nepheline, and opaques, while the intermediate rocks …

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Tectonosedimentary Evolution Of The Karacasu And Bozdoğan Basins In The Central Menderes Massif, W Anatolia, Faruk Ocakoğlu, Sanem Açikalin, Erman Özsayin, Ramazan Kadi̇r Di̇ri̇k Jan 2014

Tectonosedimentary Evolution Of The Karacasu And Bozdoğan Basins In The Central Menderes Massif, W Anatolia, Faruk Ocakoğlu, Sanem Açikalin, Erman Özsayin, Ramazan Kadi̇r Di̇ri̇k

Turkish Journal of Earth Sciences

The Karacasu and Bozdoğan basins, which trend obliquely to modern grabens in the Central Menderes Massif, are investigated in terms of morphology, basinfill architecture, and structure. Evaluation of the previous geophysical and new structural data indicates that the basins are symmetrical grabens mostly running in a N-S direction. Analysis of sedimentary facies of the basins’ infill supports the simple graben model by revealing lateral alluvial/colluvial fans in basin margins and axial fluvial/lacustrine environments in a central trough. The long-term changes between fluvial and lacustrine conditions in the basins are attributed to paleoclimatic origin. Paleostress analysis of slickensides substantiates that the …

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Probabilistic Earthquake Hazard Assessment For Ankara And Its Environs, Bülent Özmen, Berna Burçak Başbuğ Erkan Jan 2014

Probabilistic Earthquake Hazard Assessment For Ankara And Its Environs, Bülent Özmen, Berna Burçak Başbuğ Erkan

Turkish Journal of Earth Sciences

The capital and the second largest city of Turkey, Ankara, is generally considered to be safe in terms of seismic activities and earthquake hazard. However, recent studies and earthquakes experienced in the region showed that Ankara is not indeed seismically safe. As the number of studies on Ankara’s seismic hazard increases, the number of scientists who claim that the earthquake hazard in Ankara is higher than expected also increases. However, to date no detailed analysis has been undertaken as to the earthquake hazard facing Ankara. This study has compiled data from the earthquake catalogues available in Turkey and employed the …

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A Microscopic Approach To The Pedogenic Formation Of Palygorskite Associated With Quaternary Calcretes Of The Adana Area, Southern Turkey, Meryem Yeşi̇lot Kaplan, Muhsi̇n Eren, Selahatti̇n Kadi̇r, Seli̇m Kapur, Jennifer Huggett Jan 2014

A Microscopic Approach To The Pedogenic Formation Of Palygorskite Associated With Quaternary Calcretes Of The Adana Area, Southern Turkey, Meryem Yeşi̇lot Kaplan, Muhsi̇n Eren, Selahatti̇n Kadi̇r, Seli̇m Kapur, Jennifer Huggett

Turkish Journal of Earth Sciences

Quaternary calcretes in the Adana area (southern Turkey) are widespread and occur in a variety of forms such as nodular, columnar/tubular, fracture-infill, laminated hardpan, and conglomeratic crusts. Palygorskite associated with calcrete nodules, tubes, and fracture-infills in the columnar horizon and adjacent host-rock mudstones suggests a cogenetic formation. The Beta-fabric (biogenic) constituents and stable isotope values of calcretes support a pedogenic origin for calcretes and also palygorskite. Extensions of palygorskite fibre and fibre bundles from euhedral to subhedral calcite crystals in calcretes and from smectite flakes in adjacent host-rock mudstone suggest an authigenic origin related to calcretisation in which precipitation and …

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Alteration Mineral Mapping With Aster Data By Integration Of Coded Spectral Ratio Imaging And Som Neural Network Model, Mohammad Hassan Tayebi, Majid Hashemi Tangestani, Robert Keller Vincent Jan 2014

Alteration Mineral Mapping With Aster Data By Integration Of Coded Spectral Ratio Imaging And Som Neural Network Model, Mohammad Hassan Tayebi, Majid Hashemi Tangestani, Robert Keller Vincent

Turkish Journal of Earth Sciences

This study applied coded spectral ratio imaging and a self-organizing map (SOM) neural network model for subpixel classification of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data to map alteration minerals of the Masahim volcano, SE Iran. Spectra of samples were measured using a FieldSpec spectroradiometer, and were interpreted for finding key alteration minerals. Key minerals including sericite and kaolinite were selected. Thirty-six nonreciprocal spectral ratios of 9 ASTER reflective bands were created. Each spectral parameter (of 9 spectral bands and 36 spectral ratios) for the field and library mineral spectra was divided into deciles. Each decile of spectral …

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Comparison Of Life Experiences Of Men And Women In The Sciences, Tori Nicole Quist Jan 2014

Comparison Of Life Experiences Of Men And Women In The Sciences, Tori Nicole Quist

Honors Program Theses

A lack of sense of belonging and stereotype threat have been shown to contribute to women leaving the sciences (Seymour, 1997; Beasley & Fischer, 2012; Deemer et al., 2013). Contributing to this is the fact that most women find affirmation externally (through friends, family and professors) for their life decisions (Seymour, 1997; Zeldin, 2000). A set of comparative studies in 2000 and 2008 were done examining factors affecting women’s and men’s choices of majors and careers (Zeldin, 2000 and Zeldin, 2008). These studies concluded that men relied on achievements in science as the source of their career decisions to enter …

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Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Wolf, Kristofor R. Brye Jan 2014

Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Wolf, Kristofor R. Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Hydraulic fracturing is the process of injecting aqueous solutions at high pressure to break apart rock formations and increase the extraction of natural gas. The solutions are recovered and have been land-applied as one disposal technique. Excessive fluid application can result in increased soil salinity that can inhibit plant growth. The objective of this greenhouse study was to evaluate the effects of inorganic fertilizer, broiler litter, and Milorganite® and soil depth interval (0-15 cm or 0-30 cm) on the growth of bermudagrass [Cynodon dactylon (L.) Pers] in soil that was collected from a site that had been contaminated with fracturing …

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Combining Limnology And Palaeolimnology To Investigate Recent Regime Shifts In A Shallow, Eutrophic Lake, Linda Randsalu-Wendrup, Daniel J. Conley, Jacob Carstensen, Lars-Anders Hansson, Christer Brönmark, Sherilyn C. Fritz, Preetam Choudhary, Joyanto Routh, Dan Hammarlund Jan 2014

Combining Limnology And Palaeolimnology To Investigate Recent Regime Shifts In A Shallow, Eutrophic Lake, Linda Randsalu-Wendrup, Daniel J. Conley, Jacob Carstensen, Lars-Anders Hansson, Christer Brönmark, Sherilyn C. Fritz, Preetam Choudhary, Joyanto Routh, Dan Hammarlund

Department of Earth and Atmospheric Sciences: Faculty Publications

In this study, we demonstrate that an integrated approach, combining palaeolimnological records and limnological monitoring data, can increase our understanding of changing ecological patterns and processes in shallow lakes. We focused on recent regime shifts in shallow Lake Krankesjön, southern Sweden, including the collapse of the clear-water state in 1975 and its subsequent recovery in the late 1980s. We used diatom, hydrocarbon, and biogenic silica sediment records, in concert with limnological data sets on nutrient concentrations, water clarity, chlorophyll-a and water depth, to investigate the shifts. The shift from clear to turbid conditions was abrupt and occurred over 1 to …

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Lithologic Influences On Groundwater Recharge Through Incised Glacial Till From Profile To Regional Scales: Evidence From Glaciated Eastern Nebraska, John B. Gates, Gregory V. Steele, Paolo Nasta, Jozsef Szilagyi Jan 2014

Lithologic Influences On Groundwater Recharge Through Incised Glacial Till From Profile To Regional Scales: Evidence From Glaciated Eastern Nebraska, John B. Gates, Gregory V. Steele, Paolo Nasta, Jozsef Szilagyi

Department of Earth and Atmospheric Sciences: Faculty Publications

Variability in sediment hydraulic properties associated with landscape depositional and erosional features can influence groundwater recharge processes by affecting soil-water storage and transmission. This study considers recharge to aquifers underlying river-incised glaciated terrain where the distribution of clay-rich till is largely intact in upland locations but has been removed by alluvial erosion in stream valleys. In a stream-dissected glacial region in eastern Nebraska (Great Plains region of the United States), recharge estimates were developed for nested profile, aquifer, and regional scales using unsaturated zone profile measurements (matric potentials, Cl- and 3H), groundwater tracers (CFC-12 and SF6), …

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Geochemistry Of Sands Along The San Nicolás And San Carlos Beaches, Gulf Of California, Mexico: Implications For Provenance And Tectonic Setting, John Selvamony Armstrong Altrin, Ramasamy Nagarajan, Yong Il Lee, Juan José Kasper Zubillaga, Leslie Patricia Córdoba Saldaña Jan 2014

Geochemistry Of Sands Along The San Nicolás And San Carlos Beaches, Gulf Of California, Mexico: Implications For Provenance And Tectonic Setting, John Selvamony Armstrong Altrin, Ramasamy Nagarajan, Yong Il Lee, Juan José Kasper Zubillaga, Leslie Patricia Córdoba Saldaña

Turkish Journal of Earth Sciences

The weathering conditions, provenance, and tectonic setting of sands from the San Nicolás (SN) and San Carlos (SC) beaches along the Gulf of California, Mexico, have been studied using mineralogy, major element, and trace element data. The compositional similarity among 4 independent groups (each beach area consists of 2 grain-size groups, i.e. medium- and fine-grained sands) was tested statistically by the application of analysis of variance at the 99% confidence level to avoid misinterpretation. The X-ray diffraction and SEM-EDS data revealed that the fine-grained SN sands were abundant in rutile and zircon minerals. The higher SiO_2/Al_2O_3 ratio of the SN …

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Wetland Issues Affecting Waterfowl Conservation In North America, Heath M. Hagy, Scott C. Yaich, John W. Simpson, Eduardo Carrera, David A. Haukos, W.Carter Johnson, Charles R. Loesch, Fritz A. Reid, Scott E. Stephens, Ralph W. Tiner, Brett A. Werner, Greg S. Yarris Jan 2014

Wetland Issues Affecting Waterfowl Conservation In North America, Heath M. Hagy, Scott C. Yaich, John W. Simpson, Eduardo Carrera, David A. Haukos, W.Carter Johnson, Charles R. Loesch, Fritz A. Reid, Scott E. Stephens, Ralph W. Tiner, Brett A. Werner, Greg S. Yarris

Natural Resource Management Faculty Publications

This paper summarises discussions by invited speakers during a special session at the 6th North American Duck Symposium on wetland issues that affect waterfowl, highlighting current ecosystem challenges and opportunities for the conservation of waterfowl in North America. Climate change, invasive species, U.S. agricultural policy (which can encourage wetland drainage and the expansion of row-crop agriculture into grasslands), cost and competition for water rights, and wetland management for non-waterfowl species were all considered to pose significant threats to waterfowl populations in the near future. Waterfowl populations were found to be faced with significant threats in several regions, including: the Central …

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Tidal Pacing, Skipped Slips And The Slowdown Of Whillans Ice Stream, Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Douglas A. Wiens, Martin J. Pratt Jan 2014

Tidal Pacing, Skipped Slips And The Slowdown Of Whillans Ice Stream, Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Douglas A. Wiens, Martin J. Pratt

All Faculty Scholarship for the College of the Sciences

We summarize new observations of the deceleration and stick–slip motion of Whillans Ice Stream (WIS), Antarctica. We refine the location of the large sticky spots that resist motion between slip events, the locations of which are controlled by the patterns of subglacial water flow. Our examination of the long-term velocity time series for the ice stream reveals that the decadal-scale deceleration is not occurring at a steady rate, but varies at the sub-decadal timescale. This unsteady deceleration modulates the temporal evolution of a broad (~50 km across) surface-elevation bulge forming at the junction between the relatively narrow upstream portion of …

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