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Tectono-Metamorphic History Of The Eastern Taureau Shear Zone, Mauricie Area, Québec: Implications For The Exhumation Of The Mid-Crust In The Grenville Province, Renaud Soucy La Roche, Félix Gervais, Alain Tremblay, James L. Crowley, Gilles Ruffet 2015 Boise State University

Tectono-Metamorphic History Of The Eastern Taureau Shear Zone, Mauricie Area, Québec: Implications For The Exhumation Of The Mid-Crust In The Grenville Province, Renaud Soucy La Roche, Félix Gervais, Alain Tremblay, James L. Crowley, Gilles Ruffet

Geosciences Faculty Publications and Presentations

This study investigates the tectono-metamorphic history and exhumation mechanisms of the mid-crustal Mékinac-Taureau domain of the Mauricie area, central Grenville Province. Macro- and micro-structural analyses reveal the top-down-to-the-ESE sense of shear on the eastern Taureau shear zone, a major extensional structure that exhumed the mid-crustal Mékinac-Taureau domain and juxtaposed it against the lower grade rocks of the Shawinigan domain. Peak metamorphism in the Mékinac-Taureau domain, inferred to be the result of northwestward thrusting and regional crustal thickening, took place under PT conditions of 1000–1100 MPa and 820–880 °C prior to 1082 ± 20 Ma. Retrograde conditions varying from ...


Application Of Colloidal Gas Aphron Suspensions Produced From Sapindus Mukorossi For Arsenic Removal From Contaminated Soil, Soumyadeep Mukhopadhyay Dr, Sumona Mukherjee Ms, Mohd Ali Hashim Dr, Bhaskar Sen Gupta Dr 2015 SelectedWorks

Application Of Colloidal Gas Aphron Suspensions Produced From Sapindus Mukorossi For Arsenic Removal From Contaminated Soil, Soumyadeep Mukhopadhyay Dr, Sumona Mukherjee Ms, Mohd Ali Hashim Dr, Bhaskar Sen Gupta Dr

Soumyadeep Mukhopadhyay Dr

Colloidal gas aphron dispersions (CGAs) can be described as a system of microbubbles suspended homogenously in a liquid matrix. This work examines the performance of CGAs in comparison to surfactant solutions for washing low levels of arsenic from an iron rich soil. Sodium Dodecyl Sulfate (SDS) and saponin, a biodegradable surfactant, obtained from Sapindus mukorossi or soapnut fruit were used for generating CGAs and solutions for soil washing. Column washing experiments were performed in down-flow and up flow modes at a soil pH of 5 and 6 using varying concentration of SDS and soapnut solutions as well as CGAs. Soapnut ...


Kirkland D.W., 2014 - Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Leslie A. Melim 2014 University of South Florida

Kirkland D.W., 2014 - Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Leslie A. Melim

International Journal of Speleology

No abstract provided.


Radiaxial-Fibrous And Fascicular-Optic Mg-Calcitic Cave Cements: A Characterization Using Electron Backscattered Diffraction (Ebsd), Detlev K. Richter, Adrian Immenhauser, Rolf Dieter Neuser, Augusto Mangini 2014 University of South Florida

Radiaxial-Fibrous And Fascicular-Optic Mg-Calcitic Cave Cements: A Characterization Using Electron Backscattered Diffraction (Ebsd), Detlev K. Richter, Adrian Immenhauser, Rolf Dieter Neuser, Augusto Mangini

International Journal of Speleology

Electron backscattered diffraction (EBSD) applied to crystal fabric research in speleothems aids in our understanding of the origin of those fabrics. A significant advantage of this approach is the three dimensional data set of crystal c-axes. Here, we show a rare case of both convergent (radiaxial-fibrous) and divergent (fascicular-optic) orientations of the c-axes in pool calcites. The seemingly defective structure of the calcite lattice resulting in radiaxial-fibrous crystal orientations is probably caused by differential incorporation of Mg during crystal growth. The observation that radiaxial-fibrous and fascicular-optic fabrics co-exist in the same pool environment is remarkable and documents the complexity of ...


Effects Of Exposure Time On Cu(Ii) Adsorption And Retention To Iron Oxyhydroxide Nanoparticles, Anthony Torossian, Jack Jacobs, Christopher S. Kim 2014 Chapman University

Effects Of Exposure Time On Cu(Ii) Adsorption And Retention To Iron Oxyhydroxide Nanoparticles, Anthony Torossian, Jack Jacobs, Christopher S. Kim

Undergraduate Student Research Day Abstracts and Posters

Iron oxyhydroxides form naturally, often as nanoscale particles, in surface aquatic systems and represent both a powerful natural attenuation process and a potential remediation strategy for the retention and sequestration of dissolved metals in solution. This is of particular importance in mining environments due to elevated metal concentrations, acid mine drainage, and the health issues that may arise with exposure to potentially toxic metals. Such trace elements are readily transported in water supplies, increasing the geographical extent of their contamination. While metal adsorption processes to mineral surfaces have been extensively studied, desorption processes inform the long-term stability of sorbed metals ...


Arsenic Bioaccessibility As A Function Of Rainfall Exposure And Time In Mining-Impacted Sediments, Katherine Whiteman, Christopher S. Kim 2014 Chapman University

Arsenic Bioaccessibility As A Function Of Rainfall Exposure And Time In Mining-Impacted Sediments, Katherine Whiteman, Christopher S. Kim

Undergraduate Student Research Day Abstracts and Posters

Mining activities mobilize undesired trace metal(oid)s during extraction processes, exposing sediment that is easily transported by wind and rain. The presence of dangerous metal tailings is of great concern because of the implications it can hold on human health. The Red Hill Mine in Tustin is inactive; its surrounding land is entirely residential, potentially exposing residents to traces of arsenic daily.

This experiment examines the effect that rainwater has on arsenic bioaccessibility of Red Hill sediment. Gastric bioaccessibility of arsenic is greatest during periods of extreme dryness, producing an increasing correlation between the number of days since last ...


Structural And Hydrological Controls On The Development Of A River Cave In Marble (Tapagem Cave - Se Brazil), William Sallun Filho, Bruna Medeiros Cordeiro, Ivo Karmann 2014 University of South Florida

Structural And Hydrological Controls On The Development Of A River Cave In Marble (Tapagem Cave - Se Brazil), William Sallun Filho, Bruna Medeiros Cordeiro, Ivo Karmann

International Journal of Speleology

Tapagem Cave (or Devil’s Cave) is a river cave developed in the dolomite marble karst of the Serra do André Lopes (State of São Paulo, southeastern Brazil). Although this region is a plateau with significant variation in elevation and a humid subtropical climate, the cave is an anomalous feature in the André Lopes karst because there are few other caves. The marble, which is in a synclinal structure with subjacent phyllites, is a karst aquifer perched above the regional base level (Ribeira River) and has little allogenic recharge. The cave developed on a secondary anticline on the northwest flank ...


A Niobium Deposit Hosted By A Magnetite-Dolomite Carbonatite, Elk Creek Carbonatite Complex, Nebraska, Usa, Michael J. Blessington 2014 University of Nebraska - Lincoln

A Niobium Deposit Hosted By A Magnetite-Dolomite Carbonatite, Elk Creek Carbonatite Complex, Nebraska, Usa, Michael J. Blessington

Dissertations & Theses in Earth and Atmospheric Sciences

The Elk Creek Carbonatite Complex (ECCC) is a large Early Cambrian carbonatite complex that intrudes Precambrian basement rocks in Southeast Nebraska. This dolomitic carbonatite complex includes a magnetite-dolomite rock with accessory barite, ilmenite, rutile, and quartz. This rock is identified by a characteristic enrichment in niobium due to accessory pyrochlore mineralization in the form of disseminations and inclusions in ilmenite and magnetite. Pyrochlore is also present in other carbonatite rocks in the complex as an accessory mineral with sporadic local high-grade intercepts in drill cores.

Carbonatite rock samples are characterized by transmitted-light microscopy, cathodoluminescent microscopy, backscattered electron imaging (BEI), and ...


Station Exposure And Resulting Bias In Temperature Observations: A Comparison Of He Kentucky Mesonet And Asos Data, James Kyle Thompson 2014 Western Kentucky University

Station Exposure And Resulting Bias In Temperature Observations: A Comparison Of He Kentucky Mesonet And Asos Data, James Kyle Thompson

Masters Theses & Specialist Projects

Station siting, exposure, instrumentation, and time of observations influence longterm climatic records. This thesis compared and analyzed temperature data from four Kentucky Mesonet stations located in Fayette (LXGN), Franklin (LSML), Clark (WNCH), and Bullitt (CRMT) counties to two nearby Automated Surface Observation Systems (ASOS) stations in Kentucky. The ASOS stations are located at Louisville International Airport (Standiford Field - KSDF) and at Lexington Airport (Blue Grass Field - KLEX). The null hypothesis states that there is no significant difference in temperature measurements between the two types of stations. To quantify the differences in temperature measurements, geoprofiles and the following statistical procedures were ...


Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy 2014 Western Kentucky University

Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy

Masters Theses & Specialist Projects

Surface streams in karst landscapes are often characterized by high nutrient levels due to incomplete filtration through series of innumerable, below-ground conduits. Seasonal growth of the filamentous alga, Cladophora, is typically associated with nutrient-rich waters. This research compared macroinvertebrate food web structure between riverine reaches with contrasting underlying karst topography, nutrient levels, and Cladophora cover during summer 2012 and autumn 2013. Recent work in these reaches found a high correlation between Cladophora cover and nutrient content, particularly nitrate. Four questions were addressed during this study: 1. Do longitudinal trends in algal and consumer δ13C values relate to decreased DIC availability ...


Identification Of Groundwater Sources For Municipal Wells Using Geochemical Data On The Platte Alluvial Aquifer And Underlying Limestone At The Lincoln Water Well Field Near Ashland Nebraska, Juanita Cruz Torres 2014 University of Nebraska - Lincoln

Identification Of Groundwater Sources For Municipal Wells Using Geochemical Data On The Platte Alluvial Aquifer And Underlying Limestone At The Lincoln Water Well Field Near Ashland Nebraska, Juanita Cruz Torres

Dissertations & Theses in Earth and Atmospheric Sciences

Alluvial aquifer systems where pumping of municipal wells induces recharge from the adjacent river are the primary source of water for many cities. The city of Lincoln, NE has a primary water source in an alluvial aquifer adjacent to the Platte River. The Lincoln Water System manages the stream/aquifer system by using integrated models for a better understanding during periods of high stress such as a drought. The integrated models set the limestone aquifer as an impermeable boundary to understand the alluvial aquifer system without having a secondary water source. The limestone aquifer is permeable and the purpose of ...


Turbidity-Based Sediment Monitoring In Northern Thailand: Hysteresis, Variability, And Uncertainty, Shawn G. Benner, Spencer H. Wood 2014 Boise State University

Turbidity-Based Sediment Monitoring In Northern Thailand: Hysteresis, Variability, And Uncertainty, Shawn G. Benner, Spencer H. Wood

Geosciences Faculty Publications and Presentations

Annual total suspended solid (TSS) loads in the Mae Sa River in northern Thailand, determined with an automated, turbidity-based monitoring approach, were approximately 62,000, 33,000, and 14,000 Mg during the three years of observation. These loads were equivalent to basin yields of 839 (603-1170), 445 (217-462), and 192 (108-222) Mg km-2 for the 74.16-km2 catchment during 2006, 2007, and 2008, respectively. The yearly uncertainty ranges indicate our loads may be underestimated by 38-43% or overestimated by 28-33%. In determining the annual loads, discharge (Q) and turbidity (T) values were compared against 333 hand-sampled total ...


Range Of Horizontal Transport And Residence Time Of Nitrate In A Mature Karst Vadose Zone, Jiri Kamas, Jiri Bruthans, Helena Vysoka, Miroslav Kovařík 2014 University of South Florida

Range Of Horizontal Transport And Residence Time Of Nitrate In A Mature Karst Vadose Zone, Jiri Kamas, Jiri Bruthans, Helena Vysoka, Miroslav Kovařík

International Journal of Speleology

Nitrate concentrations in drips in Amaterska, Spolecnak, and Holstejnska caves situated below a 25 to 120 m thick vadose zone in the Moravian Karst, Central Europe were studied during several periods from 1992. Each cave runs below a land-use boundary between fertilized lands and forest, which enabled study of the range of horizontal components of nitrate transport in the vadose zone. Parts of the fertilized land were turned into grassland in 1998 and 2003, and the cave drips were sampled both prior and after the changes in land use. The mean residence time of nitrate is - 30 m thick vadose ...


Hairy Stalagmites, A New Biogenic Root Speleothem From Botswana, Gerhard C. Du Preez, Paolo Forti, Gerhard Jacobs, Anine Jordaan, Louwrens Tiedt 2014 University of South Florida

Hairy Stalagmites, A New Biogenic Root Speleothem From Botswana, Gerhard C. Du Preez, Paolo Forti, Gerhard Jacobs, Anine Jordaan, Louwrens Tiedt

International Journal of Speleology

Ngamiland in northwestern Botswana hosts the Gcwihaba Caves which present unique subterranean environments and host speleothems never before recorded. Cave atmospheric conditions can be extreme with temperatures as high as 28°C and relative humidity nearing 99.9%. Within Dimapo and Diviner’s Caves peculiar root speleothems that we named ‘Hairy Stalagmites’ were found. These stalagmites are closely associated with the roots of Namaqua fig (Ficus cordata) trees that enter the cave environment in search of water. Pieces of broken stalagmites were sampled from Dimapo Cave for further investigations. Stereo and electron microscopy revealed that the Hairy Stalagmites consist of ...


High-Resolution Digital 3d Models Of Algar Do Penico Chamber: Limitations, Challenges, And Potential, Ivo Silvestre M.Sc., José I. Rodrigues PhD, Mauro Figueiredo PhD, Cristina Veiga-Pires PhD 2014 University of South Florida

High-Resolution Digital 3d Models Of Algar Do Penico Chamber: Limitations, Challenges, And Potential, Ivo Silvestre M.Sc., José I. Rodrigues Phd, Mauro Figueiredo Phd, Cristina Veiga-Pires Phd

International Journal of Speleology

The study of karst and its geomorphological structures is important for understanding the relationships between hydrology and climate over geological time. In that context, we conducted a terrestrial laser-scan survey to map geomorphological structures in the karst cave of Algar do Penico in southern Portugal. The point cloud data set obtained was used to generate 3D meshes with different levels of detail, allowing the limitations of mapping capabilities to be explored.

In addition to cave mapping, the study focuses on 3D-mesh analysis, including the development of two algorithms for determination of stalactite extremities and contour lines, and on the interactive ...


Making Water Resource Decisions More "Informationally" Efficient: Development Of A Geospatial Water Rights Decision Support System For Kittitas County, Washington, Michael Pease, Jeremy Murray 2014 University of Wisconsin Milwaukee

Making Water Resource Decisions More "Informationally" Efficient: Development Of A Geospatial Water Rights Decision Support System For Kittitas County, Washington, Michael Pease, Jeremy Murray

International Journal of Geospatial and Environmental Research

In semi-arid river basins like the Yakima River Basin in central Washington State, United States of America, water demand can exceed available supply on an annual basis. More informed decisions about water supply and current allocation have the potential to improve water management. This research created a geospatial water rights database for the Yakima River Basin. The creation of a publicly available decision support system mapping water rights can provide water managers another tool to help achieve this goal. This paper describes the creation of the Decision Support System. In addition it looks at the current utility of the system ...


Allostratigraphy Of The Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada, Sarah N. Sweeney 2014 Western University

Allostratigraphy Of The Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada, Sarah N. Sweeney

University of Western Ontario - Electronic Thesis and Dissertation Repository

The Upper Ordovician units in Southwestern Ontario record the distal response to the development of the Taconic Appalachian foreland basin. The proximal representation in Ohio and Pennsylvania, contain the Utica/Point Pleasant Play (!). The relationship between the proximal and distal portions of the Taconic Appalachian foreland basin is not clearly defined due to limited chronostratigraphic data and only lithostratigraphic correlations in southwestern Ontario. The first step in evaluating the relationship between the Upper Ordovician succession in Ontario and that in the United States is to develop a high frequency allostratigraphic framework that can be integrated and compared to the frameworks ...


Can Xrf Scanning Of Speleothems Be Used As A Non-Destructive Method To Identify Paleoflood Events In Caves?, Martin Finné, Malin Kylander, Meighan Boyd, Hanna S. Sundqvist, Ludvig Löwemark 2014 University of South Florida

Can Xrf Scanning Of Speleothems Be Used As A Non-Destructive Method To Identify Paleoflood Events In Caves?, Martin Finné, Malin Kylander, Meighan Boyd, Hanna S. Sundqvist, Ludvig Löwemark

International Journal of Speleology

We have developed a novel, quick and non-destructive method for tracing flood events in caves through the analysis of a stalagmite thick section with an XRF core scanner. The analyzed stalagmite has multiple horizons of fine sediments from past flood events intercalated with areas of cleaner calcite. Flood events detected from the elemental XRF core scanning data show good agreement with the position of flood horizons identified in petrographic thin sections. The geochemical composition of the individual flood layers shows that in certain cases the clay horizons had a distinct geochemical fingerprint suggesting that it may be possible to distinguish ...


Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia 2014 University of South Florida

Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia

International Journal of Speleology

The systematic documentation of calcite fabrics in stalagmites and flowstones provides robustness to palaeoclimate interpretation based on geochemical proxies, but it has been neglected because it is difficult to transform crystal morphologies into numerical values, and construct fabric time series. Here, general criteria that allow for coding fabrics of calcite composing stalagmites and flowstones is provided. Being based on known models of fabric development, the coding ascribes sequential numbers to each fabric, which reflect climate-related parameters, such as changes in drip rate variability, bio-mediation or diagenetic modifications. Acronyms are proposed for Columnar types, Dendritic, Micrite, Microsparite and Mosaic fabrics, whose ...


Warm Water Benthic Foraminifera Document The Pennsylvanian-Permian Warming And Cooling Events – The Record From The Western Pangea Tropical Shelves, Vladimir Davydov 2014 Boise State University

Warm Water Benthic Foraminifera Document The Pennsylvanian-Permian Warming And Cooling Events – The Record From The Western Pangea Tropical Shelves, Vladimir Davydov

Geosciences Faculty Publications and Presentations

Shallow warm water benthic foraminifera (SWWBF), including all larger fusulinids (symbiont-bearing benthic foraminifera), are among the best indicators of paleoclimate and paleogeography in the Carboniferous and Permian. The distribution of benthic foraminifera in space and time constrain important tectonic, paleogeographic and climatic events at a global scale. The North American shelves during Pennsylvanian and Permian time - though geographically within the tropical belt - are characterized by temperate environments with significantly lower foraminifera diversification and rare occurrences of warm water Tethyan forms, that are in general appear in the region as a migration entities. Such environments allow documentation of warming episodes associated ...


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