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Using The Storm Water Management Model To Predict Urban Headwater Stream Hydrological Response To Climate And Land Cover Change, J. Y. Wu, Janette R. Thompson, R. K. Kolka, Kristie J. Franz, Timothy W. Stewart 2017 Iowa State University

Using The Storm Water Management Model To Predict Urban Headwater Stream Hydrological Response To Climate And Land Cover Change, J. Y. Wu, Janette R. Thompson, R. K. Kolka, Kristie J. Franz, Timothy W. Stewart

Timothy W. Stewart

Streams are natural features in urban landscapes that can provide ecosystem services for urban residents. However, urban streams are under increasing pressure caused by multiple anthropogenic impacts, including increases in human population and associated impervious surface area, and accelerated climate change. The ability to anticipate these changes and better understand their effects on streams is important for developing and implementing strategies to mitigate potentially negative effects. In this study, stream flow was monitored during April-November (2011 and 2012), and the data were used to apply the Storm Water Management Model (SWMM) for five urban watersheds in central Iowa, USA, representing ...


Pce Groundwater Quality Assessment Of The University Of Northern Iowa Campus Area, Brian Gedlinske 2017 University of Northern Iowa

Pce Groundwater Quality Assessment Of The University Of Northern Iowa Campus Area, Brian Gedlinske

Brian Gedlinske

Perchloroethylene (PCE), is a colorless, nonflammable, and relatively insoluble chlorinated solvent once widely used for dry cleaning and metal degreasing operations. Because of its past widespread use, poor solvent management practices, and environmental persistence, PCE is a common contaminant found in groundwater supplies. Potential health concerns include liver problems and increased cancer risk. This research paper presents the findings of an effort to better characterize the spatial, temporal, and transport attributes of a PCE groundwater plume that exists within the Devonian aquifer underlying the University of Northern Iowa campus and the surrounding area in Cedar Falls, Iowa. Findings reveal the ...


Review Of "Roadside Geology Of Georgia" By Pamela J.W. Gore & William Witherspoon, Michael Roden 2017 University of Georgia

Review Of "Roadside Geology Of Georgia" By Pamela J.W. Gore & William Witherspoon, Michael Roden

Georgia Journal of Science

Pamela Gore (Professor of Geology at Georgia Perimeter College) and Bill Witherspoon (Fernbank Science Center Faculty) take the reader on a tour of geological sights in Georgia viewed from the numerous highways crossing the state. This book joins a series of Roadside Guides published by Mountain Press and is one of the best of the series. The book opens with an explanation of geologic time and plate tectonics. Amply illustrated, the book includes large-scale geologic maps as well as color images of various geological features. In the introduction the authors explain that Georgia is divided into several geographic divisions, Sea ...


Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf 2017 Colorado State University, Fort Collins, CO

Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf

Stephen J Dinsmore

We studied a local population of mountain plovers (Charadrius montanus) in southern Phillips County, Montana, USA, from 1995 to 2000 to estimate annual rates of recruitment rate (f) and population change (λ). We used Pradel models, and we modeled λ as a constant across years, as a linear time trend, as year-specific, and with an additive effect of area occupied by prairie dogs (Cynomys ludovicianus). We modeled recruitment rate (f) as a function of area occupied by prairie dogs with the remaining model structure identical to the best model used to estimate λ. Our results indicated a strong negative effect ...


Genesis Of Schlottenkarren On The Avon Peninsula Of Nova Scotia (Canada) With Implications For The Geochronology Of Evaporite Karsts And Caves Of Atlantic Canada, Max Moseley 2017 independent researcher

Genesis Of Schlottenkarren On The Avon Peninsula Of Nova Scotia (Canada) With Implications For The Geochronology Of Evaporite Karsts And Caves Of Atlantic Canada, Max Moseley

International Journal of Speleology

Exposed schlottenkarren karst terrains developed on gypsum-anhydrite evaporites in the Canadian Maritime provinces might be post-Glacial landscape features (formed on glacially-denuded rocks after they are uncovered by progressive erosion of overlying glacial tills) or exhumed pre-Last Glacial Maximum (LGM) morphologies (filled with glacial till and revealed by erosion of the tills). In this paper the hydrological conditions necessary for the formation of schlottenkarren, the speleogenetic processes involved and their chronology are reconsidered and reinterpreted. It is proposed that they are essentially pre-LGM features which have survived from the Wisconsinan. It is concluded that the degree of glacial scouring and denudation ...


Composites Of Heavy Rain Producing Elevated Thunderstorms In The Central United States, Laurel P. McCoy, Patrick S. Market, Chad M. Gravelle, Charles E. Graves, Neil I. Fox, Scott M. Rochette, Joshua S. Kastman, Bohumil Svoma 2017 University of Missouri

Composites Of Heavy Rain Producing Elevated Thunderstorms In The Central United States, Laurel P. Mccoy, Patrick S. Market, Chad M. Gravelle, Charles E. Graves, Neil I. Fox, Scott M. Rochette, Joshua S. Kastman, Bohumil Svoma

Earth Sciences Faculty Publications

Composite analyses of the atmosphere over the central United States during elevated thunderstorms producing heavy rainfall are presented. Composites were created for five National Weather Service County Warning Areas (CWAs) in the region. Events studied occurred during the warm season (April–September) during 1979–2012. These CWAs encompass the region determined previously to experience the greatest frequency of elevated thunderstorms in the United States. Composited events produced rainfall of >50 mm 24 hr−1 within the selected CWA. Composites were generated for the 0–3 hr period prior to the heaviest rainfall, 6–9 hours prior to it, and 12 ...


Determining Threshold Responses Of Plant-Soil Feedbacks To Nitrogen Deposition, Lori A. Biederman, W. Stanley Harpole 2017 Iowa State University

Determining Threshold Responses Of Plant-Soil Feedbacks To Nitrogen Deposition, Lori A. Biederman, W. Stanley Harpole

Lori A. Biederman

Change associated with nitrogen deposition in the soil will alter ecosystem function and diversity. This study looks at precisely how plants and soil will interact to respond to the addition of N at various levels and in different forms.


Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera 2017 Universidad de Zaragoza

Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera

International Journal of Speleology

Evaluation of karst hazards benefits from the integration of different techniques, methodologies and approaches. Each one presents a different signature and is sensitive to certain indicators related to karst hazards. In some cases, detailed analysis permits the evaluation of representativeness either from isolated approaches or by means of integrated analyses. In this study, we present the evaluation of an area with high density of karstic collapses at different evolutionary stages through the integration of surficial, historical, geomorphological and geophysical data in order to finally define the evolutionary model for karst activity development. The obtained dataset permits to identify different steps ...


Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz de la Torre 2017 University of Málaga

Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz De La Torre

International Journal of Speleology

The geomorphological characteristics and hydrogeological functioning of a geologically heterogeneous evaporitic karst plateau in Southern Spain were studied. Land surface information (LiDAR data) was used to analyze the shape and distribution of closed depressions. An artificial tracer test and monitoring of the natural responses of the main spring have allowed to infer the karstic development of the studied system. Three dyes were injected in selected swallow holes to trace the main groundwater flowpaths and to estimate the dimension of the conduit network. Discharge, electrical conductivity and temperature were monitored in the groundwater that drains the evaporitic plateau during an individual ...


Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele 2017 Polytechnic University of Turin

Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele

International Journal of Speleology

A Messinian succession containing gypsum beds crops out in northern Italy, mainly in Piedmont and along the northern flank of the Apennine mountains in Emilia-Romagna. These gypsum bodies have been extensively quarried at the surface, in outcrops, and through underground quarries. In Emilia-Romagna these gypsum outcrops can be rather extensive, several km long and up to 1 km wide, while in Piedmont they are mostly covered by silty-marly deposits of Upper Messinian and Pliocene age and show only sparse and small outcrops. The underground quarrying of these evaporite bodies in Piedmont has allowed studying in detail their hydrogeology, and the ...


Facies Architecture And Provenance Of A Boulder-Conglomerate Submarine Channel System, Panoche Formation, Great Valley Group: A Forearc Basin Response To Middle Cretaceous Tectonism In The California Convergent Margin, Todd J. Greene, Kathleen D. Surpless 2017 Trinity University

Facies Architecture And Provenance Of A Boulder-Conglomerate Submarine Channel System, Panoche Formation, Great Valley Group: A Forearc Basin Response To Middle Cretaceous Tectonism In The California Convergent Margin, Todd J. Greene, Kathleen D. Surpless

Geosciences Faculty Research

Tectonic reorganization induced by a rapid increase in plate motion ­obliquity and rate beginning at ca. 100 Ma affected California’s Andean-style convergent margin, with concomitant changes in the accretionary prism of the Franciscan Complex, the Great Valley forearc basin, and the Sierran continental arc. Using facies analysis and a combined provenance approach, we suggest that this ca. 100 Ma tectonic signal is preserved in a Cenomanian (Upper Cretaceous) boulder-conglomerate outcrop along the San Luis Reservoir (SLR) in the southern Great Valley, which represents the thickest and coarsest deep-water deposit ever described in the Great Valley Group (GVG). We document ...


Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine 2017 University of Nebraska - Lincoln

Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine

Conservation and Survey Division

No abstract provided.


Long-Term Tillage And Nitrogen Fertilization Effects On Soil Surface Chemistry, A. Obour, J. D. Holman 2017 Kansas State University

Long-Term Tillage And Nitrogen Fertilization Effects On Soil Surface Chemistry, A. Obour, J. D. Holman

Kansas Agricultural Experiment Station Research Reports

Long-term crop management practices can affect nutrient cycling and availability to crops. This study examined the long-term effects of nitrogen (N) fertilizer application (N rates of 0, 20, 40, and 60 lb N/a) and tillage intensity (conventional tillage (CT), reduced tillage (RT), and no-tillage (NT)) on soil phosphorus (P), micronutrients, and soil acidity in a dryland winter wheat (Triticum aestivum L.)–sorghum (Sorghum bicolor L.)–fallow cropping system. Results showed soil organic matter (SOM), iron (Fe), and zinc (Zn) concentrations were greater under NT compared to CT or RT. Similarly, NT ( 32 ppm) increased P accumulation in the upper ...


Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon 2017 University of New Orleans

Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon

University of New Orleans Theses and Dissertations

Overwash, shoreface retreat, and barrier migration are common processes occurring in transgressive barrier island systems, the scale of which is exacerbated by sea level rise, subsidence and the frequency and magnitude of tropical and extratropical storms. Barrier morphology also clearly plays a key role in determining a morphological response to these processes. Using a hydrodynamic and sediment transport model (MIKE21) and selected barrier island and shoreface templates, informed by deltaic and coastal plain systems in the northern Gulf of Mexico, I performed simulations to determine barrier morphology in response to storms. A low dune with a gentle shoreface slope, characteristic ...


Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle 2017 The University of San Francisco

Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle

Master's Projects and Capstones

Groundwater is an integral piece of California’s groundwater resources. One of the most common contaminants present in groundwater is nitrate. Nitrate contamination is often a result of agricultural land use activities on the ground surface. The study area for this analysis is the Salinas Valley Groundwater Basin, an agriculturally dominated basin in coastal California. The Salinas Valley Basin is both one of the most agriculturally productive areas of the state, as well as one of the most nitrate-contaminated basins in the state. The purpose of this research was to develop a groundwater vulnerability map for nitrate pollution in the ...


Paleomagnetic Dating Of Fault Slip In The Southern Rocky Mountains, Usa, And Its Importance To An Integrated Laramide Foreland Strain Field, T. F. Wawrzyniec, Alexis K. Ault, J. W. Geissman, E. A. Erslev, S. D. Fankhauser 2017 Utah State University

Paleomagnetic Dating Of Fault Slip In The Southern Rocky Mountains, Usa, And Its Importance To An Integrated Laramide Foreland Strain Field, T. F. Wawrzyniec, Alexis K. Ault, J. W. Geissman, E. A. Erslev, S. D. Fankhauser

Alexis Ault

The Laramide orogen of the U.S. Cordillera formed in the latest Cretaceous, and deformation lasted into the earliest Oligocene. Along and proximal to the eastern and northern margins of the Colorado Plateau, deformation associated with this event mainly took place along reactivated structures. Related tectonic models invoke some role for the plateau either as a stress guide transmitting compression to the foreland or as a freely rotating microplate. Models dominated by northward displacements of the Colorado Plateau also require covariance between timing and magnitude of dextral strike-slip deformation in the eastern domain and thrust deformation in the northern domain ...


Microtextural Constraints On The Interplay Between Fluidrock Reactions And Deformation, Alexis K. Ault, Jane Selverstone 2017 Utah State University

Microtextural Constraints On The Interplay Between Fluidrock Reactions And Deformation, Alexis K. Ault, Jane Selverstone

Alexis Ault

Schists from two mylonitic localities in the footwall of a low-angle normal fault in the eastern Alps record different degrees of embrittlement during exhumation, depending on the extent to which fluid–rock reactions proceeded. At one site, graphitic schists preserve textural evidence for two metamorphic reactions that modified XCO2XCO2 and/or fluid volume: (1) reaction between graphite and aqueous fluid that increased XCO2XCO2 without changing the molar amount of fluid, and (2) replacement of titanite by rutile, calcite, and quartz. The latter reaction involved net consumption of increasingly CO2-rich fluid. Areas where the first reaction proceeded are associated with abundant ...


Record Of Paleofluid Circulation In Faults Revealed By Hematite (U-Th)/He And Apatite Fission-Track Dating: An Example From Gower Peninsula Fault Fissures, Wales, Alexis K. Ault, Max Frenzel, Peter W. Reiners, Nigel H. Woodcock, Stuart N. Thomson 2017 Utah State University

Record Of Paleofluid Circulation In Faults Revealed By Hematite (U-Th)/He And Apatite Fission-Track Dating: An Example From Gower Peninsula Fault Fissures, Wales, Alexis K. Ault, Max Frenzel, Peter W. Reiners, Nigel H. Woodcock, Stuart N. Thomson

Alexis Ault

Fault rock low-temperature thermochronometry can inform the timing, temperature, and significance of hydrothermal fluid circulation in fault systems. We demonstrate this with combined hematite (U-Th)/He (He) dating, and sandstone apatite fission-track (AFT) and apatite and zircon (U-Th)/He (He) thermochronometry from fault-related fissures on the Gower Peninsula, Wales. Hematite He dates from 141 ± 5.1 Ma to 120 ± 5.0 Ma overlap with a 131 ± 20 Ma sandstone infill AFT date. Individual zircon He dates are 402–260 Ma, reflecting source material erosion, and imply a maximum Late Permian infill depositional age. Burial history reconstruction reveals modern exposures were ...


Phanerozoic Surface History Of The Slave Craton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring 2017 Utah State University

Phanerozoic Surface History Of The Slave Craton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring

Alexis Ault

New apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85–90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the ...


Foreland-Directed Propagation Of High-Grade Tectonism In The Deep Roots Of A Paleoproterozoic Collisional Orogen, Sw Montana, Usa, Cailey B. Condit, Kevin H. Mahan, Alexis K. Ault, Rebecca M. Flowers 2017 Utah State University

Foreland-Directed Propagation Of High-Grade Tectonism In The Deep Roots Of A Paleoproterozoic Collisional Orogen, Sw Montana, Usa, Cailey B. Condit, Kevin H. Mahan, Alexis K. Ault, Rebecca M. Flowers

Alexis Ault

The study of deeply exhumed ancient collisional belts offers important constraints on geologic processes and properties complementary to inaccessible portions of the crustal column in active orogens. The ca. 1.8−1.7 Ga Big Sky orogeny in southwest Montana is a major convergent belt associated with the Proterozoic amalgamation of Laurentia. New structural, petrologic, and geochronologic data from the Northern Madison Range, crossing the NE-SW trend of the belt, record key information about the internal dynamics of the orogen. At least two phases of Big Sky−related deformation are preserved, both nearly coeval with peak metamorphic conditions of ∼0 ...


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