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Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast, Kelly Marie Sanks Dec 2018

Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast, Kelly Marie Sanks

Graduate Theses and Dissertations

Recent reports estimate that the marshes of the Mississippi Delta receive just 30% of the sediment necessary to sustain current land area1. An extensive monitoring campaign by the USGS and LCPRA provides direct measurements of sediment accumulation, subsidence rates, and deposit characteristics along the coast over the past 10 years2, allowing us to directly evaluate this sediment balance. By interpolating bulk density, organic fraction, and vertical accretion rates from 273 sites, a direct measurement of organic and inorganic sediment accumulation can be made. Results show that a total of 82 MT/year of sediment is delivered to the coast. Using a …


The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems, María José López-Galindo Nov 2018

The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems, María José López-Galindo

International Journal of Speleology

Acarines are well-documented as formative elements in the biocenosis of soils. However, their role in the construction and weathering of siliceous speleothems has received very little attention in previous research. The present study describes different groups of cavities (nesting/molting sites) excavated by these organisms in the surface of siliceous speleothems that are deposited in the fissures between various granite boulders in Southern Spain. There is evidence that there are immature stages that would survive the heat and drought of summer in the form of small larvae, or euedaphic nymphs, in the soil. This study provides the first description of how …


Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu Nov 2018

Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu

USF Tampa Graduate Theses and Dissertations

Urban Heat Island (UHI) is a growing problem worldwide. Mitigation of UHI is necessary for cities to adapt to climate change and enhance sustainable development at a city scale. Cooling cities with urban vegetation management is a sustainable solution for urban heat mitigation. Urban vegetation influences urban microclimate through the shading effect, surface roughness, and evapotranspiration. The differences in horizontal and vertical structures of urban vegetation determine the shading effect, surface roughness, and evapotranspiration. Enhancing the cooling effect of urban vegetation requires a comprehensive understanding of how vegetation structure affects UHI. The effects of horizontal structure on land surface temperature …


A Review Of Fractals In Karst, Eulogio Pardo-Igúzquiza, Peter A. Dowd, Juan J. Durán, Pedro Robledo-Ardila Nov 2018

A Review Of Fractals In Karst, Eulogio Pardo-Igúzquiza, Peter A. Dowd, Juan J. Durán, Pedro Robledo-Ardila

International Journal of Speleology

Many features of a karst massif can either be modelled using fractal geometry or have a fractal distribution. For the exokarst, typical examples include the geometry of the landscape and the spatial location and size-distribution of karst depressions. Typical examples for the endokarst are the geometry of the three-dimensional network of karst conduits and the length-distribution of caves. In addition, the hydrogeological parameters of the karst massif, such as hydraulic conductivity, and karst spring hydrographs may also exhibit fractal behaviour. In this work we review the karst features that exhibit fractal behaviour, we review the literature in which they are …


Longitudinal Study Of Water Quality In Jennings Creek, Bowling Green, Kentucky: Urbanization Impacts On Karst Groundwater, Lea Mitchell, Jason S. Polk, Rachel Kaiser, Ethan Givan, Kegan Mcclanahan Nov 2018

Longitudinal Study Of Water Quality In Jennings Creek, Bowling Green, Kentucky: Urbanization Impacts On Karst Groundwater, Lea Mitchell, Jason S. Polk, Rachel Kaiser, Ethan Givan, Kegan Mcclanahan

Posters-at-the-Capitol

Karst groundwater systems, which occur in areas where caves, sinkholes, and underground rivers dominate the landscape, are vulnerable to pollution from surface contaminants. In urban areas, like Bowling Green, Kentucky, which is home to extensive caves and groundwater supplies, the immediate transport of heavy metals, organic waste, chemicals, and other pollutants from surface activities into groundwater poses a serious threat. This research project was done to examine the water quality of urban karst sites in Bowling Green, Kentucky at Jennings Creek, which is a local river primarily fed from springs; the water quality of Jennings Creek was never tested before …


The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age, Jan Lenart, Martin Kašing, Petr Tábořík, Natalia Piotrowska, Jacek Pawlyta Oct 2018

The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age, Jan Lenart, Martin Kašing, Petr Tábořík, Natalia Piotrowska, Jacek Pawlyta

International Journal of Speleology

The Cyrilka Cave is the second longest pseudokarst cave and the longest crevice-type cave in Czechia. Developed within the headscarp area of a deep-seated landslide, the cave became a focus of scientific research in recent years when new passages were discovered. Structural analysis provided a general tectonic plan of the cave, as well as more detailed data on geometry and kinematics of the relaxed rock massif. The primary structure of NNE- to ENE-striking bedding is broken by a system of NNE-striking fissures interconnected by two continuous ENE-striking dextral fracture zones. Abundant signs of recent sinistral strike-slips within the rock massif …


Three-Dimensional Flow, Morphologic Change, And Sediment Deposition And Distribution Of Actively Evolving Neck Cutoffs Located On The White River, Arkansas, Derek Allen Richards Oct 2018

Three-Dimensional Flow, Morphologic Change, And Sediment Deposition And Distribution Of Actively Evolving Neck Cutoffs Located On The White River, Arkansas, Derek Allen Richards

LSU Doctoral Dissertations

Neck cutoffs are important and prominent features of alluvial rivers yet detailed field-based research of neck cutoffs has been insufficient to fully characterize three-dimensional flow, morphologic change, and sediment deposition and distribution. The main objectives of this research are to examine the formation and evolution of neck cutoffs by characterizing the flow field, morphology, and sediment distribution through neck cutoffs with complex planform configurations located on the White River, Arkansas. Results led to the production of two conceptual models. The flow model has main hydrodynamic characteristics of (1) tight bend flow resulting from flow redirection of nearly 180° through the …


Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren Oct 2018

Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren

Geography & Environment Publications

Planimetric change was measured on daily hydrographs over two meltwater seasons using time-lapse images of the proglacial, gravel, braided, Sunwapta River, Canada. Significant planimetric change occurred on 10-15 days per year. Area of planimetric change correlated with peak and total daily meltwater hydrograph discharge. A clear threshold discharge can be identified below which no planform activity occurs, an intermediate range over which change occurs conditionally, and a peak flow range at which significant change always occurs. Field conditions were reproduced in a physical model in a laboratory flume. Photogrammetric DEMs of bed morphology and measurements of bedload output were made …


Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson Oct 2018

Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson

Geosciences Faculty Publications

Pluvial-lake highstands in the Bonneville basin are known to be contemporaneous with periods of Quaternary glaciation. At least five lake cycles have been identified from prior studies of two deep cores (Eardley and Gvosdetsky, 1960; Eardley and others, 1973) and several isolated outcrops in the main part of the Bonneville basin and eastward in Cache Valley. These are the Lava Creek B (~620 ka, marine isotope stage MIS 16), Pokes Point (~420 ka, MIS12), Little Valley (~150 ka, MIS 6), Cutler Dam (~60 ka, MIS 4), and Bonneville (~18 ka, MIS 2) lake cycles (Oviatt and others ,1987, 1999; Lisiecki …


On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane Oct 2018

On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane

International Journal of Speleology

Seven silica biospeleothems from Cueva Charles Brewer, Chimantá Plateau, Venezuela have been successfully U-Th dated despite very low U and high detrital Th concentrations. Growth rates are low, between ~100 to ~800 µm/ka, and are greater closer to water level. Dates in unaltered material are in good stratigraphic order, but secondary silicification may compromise the U-Th system, yielding unreliable sequences of ages. Detritally-enriched layers correlate with global climate cycles of the Late Quaternary, in particular the cooler, drier phases of MIS 5d, 5a, and 4. SEM studies indicate that the peloidal material is made up of silica nano-particles assembled to …


Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus Oct 2018

Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus

Robert F. Diffendal, Jr., Publications

Geologic mapping in Nebraska and environs is an ongoing endeavor that has spanned more than 170 years, involved dozens of scientists, and evolved through many changes. Digital mapping has risen to dominance in the state only since 1996. Geologic mapping in Nebraska today concentrates on surficial mapping, which emphasizes materials exposed at the land surface and their relationships with landforms, and which is particularly relevant because non- bedrock geologic materials (regolith) lie at the surface across at least 87% of the state. Moreover, surfi cial geologic maps assist the understanding of groundwater and sand and gravel resources, to name a …


Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur Oct 2018

Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur

Masters Theses & Specialist Projects

This study investigates Mio-Pliocene mass-transport deposits (MTDs) in an understudied, hydrocarbon-rich region of the northeastern Gulf of Mexico. The research utilizes a high-quality 3D seismic dataset with an area of 635 km2, along with wireline logs and biostratigraphic data. With the help of quantitative seismic geomorphology techniques, detailed mapping of MTDs suggests a complex erosional and depositional history. Deposition of a MTD unit resulted in a 180 m topographic high that substantially influenced the distribution and morphology of subsequent MTDs, specifically the bifurcation of later mass-transport flows. This bifurcation contributed to the generation of a non-shielded erosional remnant with an …


Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden Oct 2018

Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden

Masters Theses & Specialist Projects

The geology of Ethiopia is dominated by the Ethiopian Plateau that is similar in elevation to, but aerially larger than, the Colorado Plateau. Several rivers have incised through the plateau, creating gorges that reach up to 1.5 km in depth. The plateau uplifted to its current elevation and was subsequently incised sometime after the Oligocene flood basalt event that signaled the arrival of the African Superplume below Kenya and Ethiopia. Due to its size and extent, published climate modeling has indicated that Late Cenozoic plateau formation could have been a driving force in the East African Cenozoic climate changes. Although …


Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley Oct 2018

Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley

Masters Theses & Specialist Projects

The response of a karst aquifer to storm events is often faster and more severe than that of a non-karst aquifer. This distinction is often problematic for planners and municipalities, because karst flooding does not typically occur along perennial water courses; thus, traditional flood management strategies are usually ineffective. The City of Bowling Green (CoBG), Kentucky is a representative example of an area plagued by karst flooding. The CoBG, is an urban karst area (UKA), that uses Class V Injection Wells to lessen the severity of flooding. The overall effectiveness, siting, and flooding impact of Injection Wells in UKA’s is …


Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle Oct 2018

Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle

Masters Theses & Specialist Projects

Greenhouse gases (GHGs) are a major global environmental concern, because their concentrations have continuously increased over the past few centuries, due to global population growth, fossil fuel dependency, and the Industrial Revolution. Since these gases are naturally occurring phenomena, they will never be completely eliminated. Efforts to reduce them span numerous scientific attempts, with minimal improvements in reducing their atmospheric concentrations. In agricultural land practices, greenhouse gases are common byproducts that affect the atmosphere and, potentially, the groundwater where livestock and fertilizers are key contributors. Little is known about the fate of such greenhouse gases in dissolved form, known as …


Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment, Hali Steinmann Oct 2018

Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment, Hali Steinmann

Masters Theses & Specialist Projects

Much of the pioneering work on caves of the Cumberland Plateau (province spanning Tennessee, Kentucky, Alabama, and Georgia) has been stratigraphically located within the Mississippian Bangor and Monteagle Limestones, wherein some of the region’s largest and most spectacular caves occur. Of interest to the understanding of this karst landscape, but severely underrepresented in the literature thereof, are caves and karst features in a heterogeneous sequence of clastics and carbonates known collectively as the Pennington Formation (Upper Mississippian). This work consisted of a regional study of Pennington caves on the western Cumberland Plateau escarpment (Alabama and Tennessee), and a case study …


Land-Use Impacts On The Hydrology Of The Hidden River Groundwater Subbasin, Horse Cave, Hart County, Kentucky, Cesalea N. Osborne Oct 2018

Land-Use Impacts On The Hydrology Of The Hidden River Groundwater Subbasin, Horse Cave, Hart County, Kentucky, Cesalea N. Osborne

Masters Theses & Specialist Projects

No abstract provided.


Laguna Madre Estuary Program Environmental Strategic Plan - Final Report, Kim D. Jones, Lucy Camacho, T. Sinha, Omar Al-Qudah, Hudson R. Deyoe, Augusto Sanchez Gonzalez, Jungseok Ho, Javier Guerrero Sep 2018

Laguna Madre Estuary Program Environmental Strategic Plan - Final Report, Kim D. Jones, Lucy Camacho, T. Sinha, Omar Al-Qudah, Hudson R. Deyoe, Augusto Sanchez Gonzalez, Jungseok Ho, Javier Guerrero

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The goal of this effort is to establish a framework of fundamental information and critical ideas to serve as a basis to assist in supporting legislation to found the 29th National Estuary Program for the Laguna Madre of the Gulf coast of Texas.

The National Estuary Program (NEP) was established by the Clean Water Act Amendments of 1987 (Section 320) to protect nationally significant estuaries threatened by development, pollution and overuse. The U.S. Environmental Protection Agency administers the NEP. The Corpus Christi Bay NEP (now the Coastal Bend Bays and Estuary Program) was among the last estuaries accepted into the …


Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers, Sarah Peirce, Peter Ashmore, Pauline Leduc Sep 2018

Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers, Sarah Peirce, Peter Ashmore, Pauline Leduc

Geography & Environment Publications

Evolution of bed material mobility and bedload grain size distributions under a range of discharges is rarely observed in braiding in gravel-bed rivers. Yet, the changing of bedload grain size distributions with discharge is expected to be different from laterally stable, threshold, channels on which most gravel bedload theory and observation are based. Here, simultaneous observations of flow, bedload transport rate, and morphological change were made in a physical model of a gravel-bed braided river to document the evolution of grain size distributions and bed mobility over three experimental event hydrographs. Bedload transport rate and grain size distributions were measured …


Using Aviris And Machine Learning To Map And Discriminate Bull Kelp And Giant Kelp Along The Pacific Coast Of The United States, Tanner Thompson, Dr. Ryan Jensen Sep 2018

Using Aviris And Machine Learning To Map And Discriminate Bull Kelp And Giant Kelp Along The Pacific Coast Of The United States, Tanner Thompson, Dr. Ryan Jensen

Journal of Undergraduate Research

Kelp forests provide food and shelter for many organisms, and they are an important part of coastal ecosystems throughout the world. Along the Pacific coast of the United States, kelp forests are made up of two species of kelp: bull kelp (Nereocystis Leutkana) and giant kelp (Macrocystis Pyrifera). While similar, these two species are physiologically and structurally different.


The Sisal Database: A Global Resource To Document Oxygen And Carbon Isotope Records From Speleothems, Kamolphat Atsawawaranunt, Laia Comas-Bru, Sahar Amirnezhad Mozhdehi, Michael Deininger, Sandy P. Harrison, Andy Baker, Meighan Boyd, Nikita Kaushal, Syed Masood Ahmad, Yassine Ait Brahim, Monica Arienzo, Petra Bajo, Kerstin Braun, Yuval Burstyn, Sakonvan Chawchai, Wuhui Duan, István Gábor Hatvani, Jun Hu, Zoltán Kern, Inga Labuhn, Matthew Lachniet, Franziska A. Lechleitner, Andrew Lorrey, Carlos Pérez-Mejías, Robyn Pickering, Nick Scroxton, Sisal Working Group Members Sep 2018

The Sisal Database: A Global Resource To Document Oxygen And Carbon Isotope Records From Speleothems, Kamolphat Atsawawaranunt, Laia Comas-Bru, Sahar Amirnezhad Mozhdehi, Michael Deininger, Sandy P. Harrison, Andy Baker, Meighan Boyd, Nikita Kaushal, Syed Masood Ahmad, Yassine Ait Brahim, Monica Arienzo, Petra Bajo, Kerstin Braun, Yuval Burstyn, Sakonvan Chawchai, Wuhui Duan, István Gábor Hatvani, Jun Hu, Zoltán Kern, Inga Labuhn, Matthew Lachniet, Franziska A. Lechleitner, Andrew Lorrey, Carlos Pérez-Mejías, Robyn Pickering, Nick Scroxton, Sisal Working Group Members

Geoscience Faculty Research

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide out-of-sample evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are …


Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake Sep 2018

Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake

Publications and Research

Accurate estimates of long-term land surface temperature (Ts) and near-surface air temperature (Ta) at finer spatio-temporal resolutions are crucial for surface energy budget studies, for environmental applications, for land surface model data assimilation, and for climate change assessment and its associated impacts. The Atmospheric Infrared Sounder (AIRS) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua satellite provide a unique opportunity to estimate both temperatures twice daily at the global scale. In this study, differences between Ta and Ts were assessed locally over regions of North America from 2009 to 2013 …


Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń Sep 2018

Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń

International Journal of Speleology

The backslope of a sandstone cuesta in the Broumov Highland (Czechia) is cut by a complex network of canyons. Long sections of canyons have thick boulder fills which are difficult to reconcile with simple rock fall and talus development scenario. Boulder caves occur within these fills and their lowermost parts are drained by streams that evacuate fine loose sandy material produced by weathering and mechanical erosion. These boulder fills are explained as largely in situ, residual features, left after subsurface selective disintegration of rock mass, mainly joint-guided, and removal of grains by underground water. Evacuation of fines leaves voids …


Characterizing Hydrological Connectivity Of Artificial Ditches In Zoige Peatlands Of Qinghai-Tibet Plateau, Peng Gao, Zhiwei Li, Yuchi You Sep 2018

Characterizing Hydrological Connectivity Of Artificial Ditches In Zoige Peatlands Of Qinghai-Tibet Plateau, Peng Gao, Zhiwei Li, Yuchi You

Geography and the Environment - Faculty Scholarship

Peats have the unique ability of effectively storing water and carbon. Unfortunately, this ability has been undermined by worldwide peatland degradation. In the Zoige Basin, located in the northeastern Qinghai-Tibet Plateau, China, peatland degradation is particularly severe. Although climate change and (natural and artificial) drainage systems have been well-recognized as the main factors catalyzing this problem, little is known about the impact of the latter on peatland hydrology at larger spatial scales. To fill this gap, we examined the hydrological connectivity of artificial ditch networks using Google Earth imagery and recorded hydrological data in the Zoige Basin. After delineating from …


Impact Of Climate Change On The Transition Of Neanderthals To Modern Humans In Europe, Michael Staubwasser, Virgil Drăgușin, Bogdan P. Onac, Sergey Assonov, Vasile Ersek, Dirk L. Hoffman, Daniel Veres Sep 2018

Impact Of Climate Change On The Transition Of Neanderthals To Modern Humans In Europe, Michael Staubwasser, Virgil Drăgușin, Bogdan P. Onac, Sergey Assonov, Vasile Ersek, Dirk L. Hoffman, Daniel Veres

School of Geosciences Faculty and Staff Publications

Two speleothem stable isotope records from East-Central Europe demonstrate that Greenland Stadial 12 (GS12) and GS10—at 44.3–43.3 and 40.8–40.2 ka—were prominent intervals of cold and arid conditions. GS12, GS11, and GS10 are coeval with a regional pattern of culturally (near-)sterile layers within Europe’s diachronous archeologic transition from Neanderthals to modern human Aurignacian. Sterile layers coeval with GS12 precede the Aurignacian throughout the middle and upper Danube region. In some records from the northern Iberian Peninsula, such layers are coeval with GS11 and separate the Châtelperronian from the Aurignacian. Sterile layers preceding the Aurignacian in the remaining Châtelperronian domain are coeval …


Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon Graham, Marco Guzmán-Speziale, Douglas Hernandez, Vladimir Kostoglodov, Peter Lafemina, Neal Lord, Cécile Lasserre, Hélène Lyon-Caen, Manuel Rodriguez Maradiaga, Robert Mccaffrey, Enrique Molina, Jeffrey Rivera, Robert Rogers, Alejandra Staller Sep 2018

Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon Graham, Marco Guzmán-Speziale, Douglas Hernandez, Vladimir Kostoglodov, Peter Lafemina, Neal Lord, Cécile Lasserre, Hélène Lyon-Caen, Manuel Rodriguez Maradiaga, Robert Mccaffrey, Enrique Molina, Jeffrey Rivera, Robert Rogers, Alejandra Staller

Geology Faculty Publications and Presentations

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 Mw = 7.3 Swan Islands fault strike-slip earthquake and the 2012 Mw = 7.3 El Salvador and Mw = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous, time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the coseismic and post-seismic deformation. Our geodetic …


Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon E. Graham, Robert Mccaffrey, Multiple Additional Authors Sep 2018

Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon E. Graham, Robert Mccaffrey, Multiple Additional Authors

Geology Faculty Publications and Presentations

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 Mw = 7.3 Swan Islands fault strike-slip earthquake and the 2012 Mw = 7.3 El Salvador and Mw = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous, time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the coseismic and post-seismic …


Long-Term Evolution Of Sand Transport Through A River Network: Relative Influences Of A Dam Versus Natural Changes In Grain Size From Sand Waves, David J. Topping, Erich R. Mueller, John C. Schmidt, Ronald E. Griffiths, David J. Dean, Paul E. Grams Aug 2018

Long-Term Evolution Of Sand Transport Through A River Network: Relative Influences Of A Dam Versus Natural Changes In Grain Size From Sand Waves, David J. Topping, Erich R. Mueller, John C. Schmidt, Ronald E. Griffiths, David J. Dean, Paul E. Grams

Watershed Sciences Faculty Publications

Temporal and spatial nonuniformity in supplies of water and sand in a river network leads to sand transport that is in local disequilibrium with the upstream sand supply. In such river networks, sand is transported downstream as elongating waves in which coupled changes in grain size and transport occur. Depending on the magnitude of each sand-supplying event and the interval between such events, changes in bed-sand grain size associated with sand-wave passage may more strongly regulate sand transport than do changes in water discharge. When sand transport is controlled more by episodic resupply of sand than by discharge, upstream dam …


Modeling Error Learning Based Post-Processor Framework For Hydrologic Models Accuracy Improvement, Rui Wu, Lei Yang, Chao Chen, Sajjad Ahmad, Sergiu M. Dascalu, Frederick C. Harris Jr. Aug 2018

Modeling Error Learning Based Post-Processor Framework For Hydrologic Models Accuracy Improvement, Rui Wu, Lei Yang, Chao Chen, Sajjad Ahmad, Sergiu M. Dascalu, Frederick C. Harris Jr.

Civil and Environmental Engineering and Construction Faculty Research

This paper studies how to improve the accuracy of hydrologic models using machine learning models as postprocessors and presents possibilities to reduce the workload to create an accurate hydrologic model by removing the calibration step. It is often challenging to develop an accurate hydrologic model, due to the time-consuming model calibration procedure and the non-stationarity of hydrologic data. Our findings show that the errors of hydrologic models are correlated with model 5 inputs. Thus motivated, we propose a modeling error learning based post-processor framework by leveraging this correlation to improve the accuracy of a hydrologic model. The key idea is …


The Geotraces Intermediate Data Product 2017, Conwaygeotraces, Tim M. Conway Aug 2018

The Geotraces Intermediate Data Product 2017, Conwaygeotraces, Tim M. Conway

School of Geosciences Faculty and Staff Publications

The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results …