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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 Université du Québec à Montréal

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 ...


Peat Formation Concentrates Arsenic Within Sediment Deposits Of The Mekong Delta, Jason W. Stuckey, Michael V. Schaefer, Benjamin D. Kocar, Jessica Dittmar, Juan Lezama Pacheco, Shawn G. Benner, Scott Fendorf 2015 Stanford University

Peat Formation Concentrates Arsenic Within Sediment Deposits Of The Mekong Delta, Jason W. Stuckey, Michael V. Schaefer, Benjamin D. Kocar, Jessica Dittmar, Juan Lezama Pacheco, Shawn G. Benner, Scott Fendorf

Geosciences Faculty Publications and Presentations

Mekong River Delta sediment bears arsenic that is released to groundwater under anaerobic conditions over the past several thousand years. The oxidation state, speciation, and distribution of arsenic and the associated iron bearing phases are crucial determinants of As reactivity in sediments. Peat from buried mangrove swamps in particular may be an important host, source, or sink of arsenic in the Mekong Delta. The total concentration, speciation, and reactivity of arsenic and iron were examined in sediments in a Mekong Delta wetland by X-ray fluorescence spectrometry (XRF), X-ray absorption spectroscopy (XAS), and selective chemical extractions. Total solid-phase arsenic concentrations in ...


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 University of Malaya

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 ...


4-D Evolution Of Anticlines And Implications For Hydrocarbon Exploration Within The Zagros Fold-Thrust Belt, Kurdistan Region, Iraq, Mjahid M. Zebari, Caroline M. Burberry 2015 Salahaddin University-Erbil, Iraq

4-D Evolution Of Anticlines And Implications For Hydrocarbon Exploration Within The Zagros Fold-Thrust Belt, Kurdistan Region, Iraq, Mjahid M. Zebari, Caroline M. Burberry

Papers in the Earth and Atmospheric Sciences

The Zagros Fold-Thrust Belt, extending from southern Iran, through northern Iraq and into Turkey, is characterized by elongate NW-trending anticlines that house large hydrocarbon accumulations. In recent years, the Kurdistan region of northern Iraq has become an area of interest for both structural studies and petroleum exploration-related investigation. Key questions to be answered concern the nature of the anticlines and whether the geometry of any associated thrusts can be predicted from surface geomorphology, as well the 4-D evolution of the area and along-strike continuity of the anticlines. To address these questions, this study combines field data, remote-sensing data concerning the ...


The Effect Of Basement Fault Reactivation On The Triassic—Recent Geology Of Kurdistan, North Iraq, Caroline M. Burberry 2015 University of Nebraska - Lincoln

The Effect Of Basement Fault Reactivation On The Triassic—Recent Geology Of Kurdistan, North Iraq, Caroline M. Burberry

Papers in the Earth and Atmospheric Sciences

The Zagros orogenic belt is underlain by a complex faulted Precambrian basement. Major fault trends originating in this basement have been invoked to explain large-scale structural changes along the strike of the orogen, e.g. the development of the Kirkuk Embayment (Kurdistan, Iraq) and the Lurestan Salient (Iran). However, within the Kirkuk Embayment, these structural trends have not previously been considered as an interacting group of faults which are periodically reactivated. This contribution first presents a revised basement fault map for the Kirkuk Embayment, created from interpreted gravity data, existing fault maps and remote sensing lineament analyses. This map is ...


Groundwater Lowering And Stream Incision Rates In The Central Appalachian Mountains Of West Virginia, Usa, Gregory S. Springer, Holly A. Poston, Ben Hardt, Harold D. Rowe 2014 Ohio University - Main Campus

Groundwater Lowering And Stream Incision Rates In The Central Appalachian Mountains Of West Virginia, Usa, Gregory S. Springer, Holly A. Poston, Ben Hardt, Harold D. Rowe

International Journal of Speleology

Surface channel incision rates are of broad geomorphological interest because they set the boundary conditions for landscape change by affecting changes in local relief and hillslope angles. We report groundwater table lowering rates associated with subsurface Buckeye Creek and the surface channel of Spring Creek in southeastern West Virginia, USA. The mountainous watersheds have drainage areas of 14 km2 and 171 km2, respectively. The lowering rates are derived from U/Th-dating of stalagmites and the paleomagnetostratigraphy of clastic sediments in Buckeye Creek Cave. The oldest stalagmites have a minimum age of 0.54 Ma and we use a ...


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 Western Illinois University

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.


The Effects Of Dissolution On The Silicon And Oxygen Isotope Compositions Of Silica Phytoliths, Andrea Prentice 2014 The University of Western Ontario

The Effects Of Dissolution On The Silicon And Oxygen Isotope Compositions Of Silica Phytoliths, Andrea Prentice

University of Western Ontario - Electronic Thesis and Dissertation Repository

The δ30Si and δ18O values of silica phytoliths have applications for reconstructing paleoenvironmental conditions. This study examines the effect of partial dissolution and burning of phytoliths on their isotopic compositions, dissolution behaviour, and physical characteristics (specific surface area, mean particle size, and visual appearance) and discusses problems with the use of phytolith δ18O and δ30Si values that have been modified in soils in paleoclimate reconstruction. Dissolution experiments were conducted in batch reactors under a range of pH (4-10) and temperature (4-44˚C) conditions. The δ18O and δ30Si values ...


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 Ruhr-University-Bochum

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 ...


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 Geological Institute, State of São Paulo Environment Department, Brazil

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 ...


Morphological And Structural Mapping Of The Oudemans Impact Crater Layered Central Uplift, Mars, Bahareh Kasmai 2014 The University of Western Ontario

Morphological And Structural Mapping Of The Oudemans Impact Crater Layered Central Uplift, Mars, Bahareh Kasmai

University of Western Ontario - Electronic Thesis and Dissertation Repository

Central uplifts in large meteorite impact craters provide valuable information about the subsurface geology of planetary bodies. Compared to impact craters on Earth, Martian central uplifts can be well exposed and can be mapped in detail by using satellite imagery. Central uplifts preserve morphological and structural features formed as result of the combination of emplacement during the impact process, post impact modification, and erosion over time. In this study, the Oudemans Crater central uplift (the largest central uplift with layers on Mars) was investigated. Oudemans (9.89 S, 268.1 E) is 124 km in diameter and is located in ...


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 ...


Ensemble Prediction And Data Assimilation For Operational Hydrology, Dong-Jun Seo, Yuqiong Liu, Hamid Moradkhani, Albrecht Weerts 2014 University of Texas at Arlington

Ensemble Prediction And Data Assimilation For Operational Hydrology, Dong-Jun Seo, Yuqiong Liu, Hamid Moradkhani, Albrecht Weerts

Civil and Environmental Engineering Faculty Publications and Presentations

This special section in the Journal of Hydrology will discuss the need for advancing hydrologic ensemble prediction and DA.


Earthquake And Tsunami Forecasts: Relation Of Slow Slip Events To Subsequent Earthquake Rupture, Timothy H. Dixon, Yan Jiang, Rocco Malservisi, Robert McCaffrey, Nicholas Voss, Marino Protti, Victor Gonzalez 2014 University of South Florida

Earthquake And Tsunami Forecasts: Relation Of Slow Slip Events To Subsequent Earthquake Rupture, Timothy H. Dixon, Yan Jiang, Rocco Malservisi, Robert Mccaffrey, Nicholas Voss, Marino Protti, Victor Gonzalez

Geology Faculty Publications and Presentations

The 5 September 2012 Mw 7.6 earthquake on the Costa Rica subduction plate boundary followed a 62-y interseismic period. High-precision GPS recorded numerous slow slip events (SSEs) in the decade leading up to the earthquake, both up-dip and down-dip of seismic rupture. Deeper SSEs were larger than shallower ones and, if characteristic of the interseismic period, release most locking down-dip of the earthquake, limiting down-dip rupture and earthquake magnitude. Shallower SSEs were smaller, accounting for some but not all interseismic locking. One SSE occurred several months before the earthquake, but changes in Mohr–Coulomb failure stress were probably too ...


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 ...


Urban Seismology For Groundwater Characterization In A Developing Country: Challenges And Rewards, John H. Bradford, Kyle Lindsay, Steve Silliman, Nicaise Yalo, Moussa Boukari 2014 Boise State University

Urban Seismology For Groundwater Characterization In A Developing Country: Challenges And Rewards, John H. Bradford, Kyle Lindsay, Steve Silliman, Nicaise Yalo, Moussa Boukari

Geosciences Faculty Publications and Presentations

The coastal city of Cotonou in the developing country of Bénin, West Africa, is a large population center that is facing a serious threat to the sustainability of its freshwater supply. The city relies on the Godomey aquifer for domestic water, but the aquifer is undergoing saltwater intrusion. This problem is likely to worsen without significant steps to improve management of the water supply. Aquifer continuity and saltwater flow paths are poorly understood, but that information is critical to ensure sustainable access to freshwater in this growing urban center. In January 2012, a two-year geophysical investigation was begun with the ...


Investigating The Effects Of Urbanization On Residual Forest Soils In Knox Co., Tennessee, Benjamin Lee Reichert 2014 University of Tennessee - Knoxville

Investigating The Effects Of Urbanization On Residual Forest Soils In Knox Co., Tennessee, Benjamin Lee Reichert

Masters Theses

As the process of urbanization advances across the country, so does the importance of urban forests, which include both trees and the soils in which they grow. Soil microbial biomass, which plays a critical role in nutrient transformation in urban ecosystems, is affected by factors such as soil type and the availability of water, carbon, and nitrogen. However, the microbial dynamics of urban forest soils remain largely unknown. A key mechanistic link between plant species diversity and ecosystem function is heterotrophic microbial communities that inhabit the soil and mediate principal processes that control ecosystem carbon (C) and nitrogen (N) cycling ...


Transport Of Fecal Pollution Indicators: Impacts From The Land Spreading Of Liquid Manure On Water Quality, Derek Lee Street 2014 University of Tennessee - Knoxville

Transport Of Fecal Pollution Indicators: Impacts From The Land Spreading Of Liquid Manure On Water Quality, Derek Lee Street

Masters Theses

This thesis is a case study to determine if groundwater and/or drainage tiles are important pathways for fecal migration to streams resulting from the application of liquid manure to cropland at a small dairy farm, the Little River Animal and Environmental Unit, near Townsend, TN. Traditional biological indicators, coliforms and E.coli, were used in conjunction with a bovine specific Bacteroides assay to measure fecal microbes. Total nitrates, turbidity, and other chemical parameters for water quality also were used to identify related fecal contamination. This thesis covers three separate manure applications. The first manure application occurred in May 2013 ...


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