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Flowstone Growth In Gournier River (Vercors, France): A Diachronic Landscape Analysis By 3d Modelling And Photo Draping, Kim Genuite, Yves Perrette, Stéphane Jaillet Dec 2017

Flowstone Growth In Gournier River (Vercors, France): A Diachronic Landscape Analysis By 3d Modelling And Photo Draping, Kim Genuite, Yves Perrette, Stéphane Jaillet

International Journal of Speleology

Calcite surface has been reported by cavers and scientists over the last decades. Here, we present a methodological work aimed at quantifying that growth. We suggest a method of draping old photographs of a part of the Gournier Cave onto a 3D model. This work relies on a collection of photographs taken by cavers. We have chosen to study a site for which the maximum number of photographs was available. The series of photographs over time makes it possible to overcome the limitation of calcite crust dating. The acquisition of the 3D model has been achieved using terrestrial LIDAR. Then, …


Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz Dec 2017

Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz

International Journal of Speleology

The Carajás Mineral Province has one of the largest concentrations of caves in Brazil, and its iron ore is among the country’s main exports. As a result of iron ore intense extraction, new environmental policies have been implemented. In an attempt to balance economic activity and environmental conservation, an inventory and a relevance-based classification of caves were implemented in 2008 as criteria for environmental licensing of mining ventures. This implementation motivated the present study of phosphate speleothems in Carajás’ caves developed in ferriferous rocks. The objectives of this study are to describe the phosphate minerals and their formation processes based …


Investigation Of Sediment Ridges Using Bathymetry And Backscatter Near Clearwater, Florida, Lewis Stewart Nov 2017

Investigation Of Sediment Ridges Using Bathymetry And Backscatter Near Clearwater, Florida, Lewis Stewart

USF Tampa Graduate Theses and Dissertations

Changes in sediment morphology on the West Florida Shelf is investigated over a 14-year time period using multibeam bathymetry and backscatter in water depths between 10 m and 20 m, off the coast of Indian Rocks Beach, Pinellas County, Florida. Bathymetric surveys collected in 2002 (Kongsberg EM 3000 at 300 kHz) and 2016 (Reson 7125 at 400 kHz) were processed using CARIS Hips and Sips to create bathymetric maps and backscatter images. These data were then interpreted and compared in order to test hypotheses and answer questions related to sediment migration and sediment volume change.

The following questions prompted this …


Cave Monitoring In The Béke And Baradla Caves (Northeastern Hungary): Implications For The Conditions For The Formation Cave Carbonates, György Czuppon, Attila Demény, Szabolcs Leél-Őssy, Mihály Óvari, Mihály Molnár, József Stieber, Klaudia Kiss, Krisztina Kármán, Gergely Surányi, László Haszpra Nov 2017

Cave Monitoring In The Béke And Baradla Caves (Northeastern Hungary): Implications For The Conditions For The Formation Cave Carbonates, György Czuppon, Attila Demény, Szabolcs Leél-Őssy, Mihály Óvari, Mihály Molnár, József Stieber, Klaudia Kiss, Krisztina Kármán, Gergely Surányi, László Haszpra

International Journal of Speleology

In order to use speleothems in the reconstruction of past climate and environmental changes it is necessary to understand the environmental and hydrological processes that determine the physico-chemical conditions of carbonate precipitation and hence speleothem formation. Therefore, in this study an extended monitoring program was conducted in the Béke and Baradla caves located in the Aggtelek region (Northeastern Hungary). The studied caves are rich in speleothem and flowstone occurrences with great potential for paleoclimatology studies. The monitoring activity included measurements of atmospheric and cave temperatures, CO2 concentration in cave air, as well as chemical and isotopic compositions of water …


Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt Nov 2017

Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt

USF Tampa Graduate Theses and Dissertations

In order to determine the timing of Antarctic ice sheet retreat and advance during the Late Quaternary, various tools are used to measure the age of marginal marine sediments. Carbonate 14C dating is a well-established approach, but requires foraminiferal microfossils, shells or other carbonate materials that are rare in most Antarctic regions, and may also suffer from vital effects, which can result in variability of up to 500 years in living organisms. Bulk acid insoluble organic (AIO) 14C dates are frequently as an alternative, but this approach works best where high productivity and sedimentation rates reign, and not too well …


Imaging Wetland Hydrogeophysics: Applications Of Critical Zone Hydrogeophysics To Better Understand Hydrogeologic Conditions In Coastal And Inland Wetlands And Waters, Christine Marie Downs Nov 2017

Imaging Wetland Hydrogeophysics: Applications Of Critical Zone Hydrogeophysics To Better Understand Hydrogeologic Conditions In Coastal And Inland Wetlands And Waters, Christine Marie Downs

USF Tampa Graduate Theses and Dissertations

This dissertation consists of three projects utilizing electric and electromagnetic (EM) methods to better understand critical-zone hydrogeologic conditions in select Florida wetlands and waters.

First, a time-lapse electrical resistivity (ER) survey was conducted in section of mangrove forest on a barrier island in southeast Florida to image changes in pore-water salinity in the root zone. ER data show the most variability in the root zone over a 24-hour period, and, generally, the ground is more resistive during the day than overnight.

Second, a suite of three-dimensional forward models, based on varying lateral boundaries and conductivities typical of a coastal wetland, …


Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks, Giovanni Badino Nov 2017

Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks, Giovanni Badino

International Journal of Speleology

The first layers of rock underground are in thermal contact with the external atmosphere mainly through infiltrating meteoric water. This relatively cool zone absorbs rising geothermal energy, which heats the water. If the aquifer consists of gypsum, halite or quartzite, the water at those depths is usually salt-saturated, so the increase in temperature renders the water aggressive again. This in turn leads to rock dissolution and formation of phreatic conduits. This way, the geothermal flow creates caves that do not necessarily reach the surface. This paper analyzes the speed of the excavation, which, in different types of rocks, depends only …


Evaluating Satellite And Supercomputing Technologies For Improved Coastal Ecosystem Assessments, Matthew James Mccarthy Nov 2017

Evaluating Satellite And Supercomputing Technologies For Improved Coastal Ecosystem Assessments, Matthew James Mccarthy

USF Tampa Graduate Theses and Dissertations

Water quality and wetlands represent two vital elements of a healthy coastal ecosystem. Both experienced substantial declines in the U.S. during the 20th century. Overall coastal wetland cover decreased over 50% in the 20th century due to coastal development and water pollution. Management and legislative efforts have successfully addressed some of the problems and threats, but recent research indicates that the diffuse impacts of climate change and non-point source pollution may be the primary drivers of current and future water-quality and wetland stress. In order to respond to these pervasive threats, traditional management approaches need to adopt modern …


The Role Of High-Elevation Headwater Runoff In Streamflow Generation And Water Supply In The Northern Andes, Colombia, Laura Lotero Lozano Nov 2017

The Role Of High-Elevation Headwater Runoff In Streamflow Generation And Water Supply In The Northern Andes, Colombia, Laura Lotero Lozano

USF Tampa Graduate Theses and Dissertations

Water security requires that sufficient quantities of water be available at critical times. This is particularly challenging for high-intensity urban and agricultural settings. In underdeveloped nations, streamflow is commonly the preferred water source, as it is readily available and delivered cost-free to users. Yet, the sources of these critical streamflows are often unknown. This issue is salient in the Northern Andes, where basic knowledge of controlling factors for the quantity, quality, and timing of runoff is lacking. High-elevation headwaters are the primary catchment areas in the Northern Andes, but the extent of water providing to municipalities in the Northern Andes …


A Geochemical And Petrological Analysis Of The San Rafael Volcanic Field, Utah, Danielle Koebli Nov 2017

A Geochemical And Petrological Analysis Of The San Rafael Volcanic Field, Utah, Danielle Koebli

USF Tampa Graduate Theses and Dissertations

The San Rafael Volcanic Field, Utah, is a 4.6 Ma extinct monogenetic field that is found in the Northern Transition Zone of the Colorado Plateau. The field has been eroded, leaving the dikes, conduits, and sills visible. Within the sills we see evidences of immiscibility in the form of an intermediate syenite (~50 wt% SiO2) enclosed in a mafic shonkinite (~48 wt % SiO2). Field relations indicate that sills were formed due to single events (Richardson et al., 2015), which makes in-situ differentiation the process at the origin of both rock types. Geochemical data supports differentiation …


Climatic Control On Icelandic Volcanic Activity During The Mid-Holocene, Graeme T. Swindles, Elizabeth J. Watson, Ivan P. Savov, Ian T. Lawson, Anja Schmidt, Andrew Hooper, Claire L. Cooper, Charles B. Connor, Manuel Gloor, Jonathan L. Carrivick Nov 2017

Climatic Control On Icelandic Volcanic Activity During The Mid-Holocene, Graeme T. Swindles, Elizabeth J. Watson, Ivan P. Savov, Ian T. Lawson, Anja Schmidt, Andrew Hooper, Claire L. Cooper, Charles B. Connor, Manuel Gloor, Jonathan L. Carrivick

School of Geosciences Faculty and Staff Publications

Human-induced climate change is causing rapid melting of ice in many volcanically active regions. Over glacial-interglacial time scales changes in surface loading exerted by large variations in glacier size affect the rates of volcanic activity. Numerical models suggest that smaller changes in ice volume over shorter time scales may also influence rates of mantle melt generation. However, this effect has not been verified in the geological record. Furthermore, the time lag between climatic forcing and a resultant change in the frequency of volcanic eruptions is unknown. We present empirical evidence that the frequency of volcanic eruptions in Iceland was affected …


Darwin Day In Deep Time: Promoting Evolutionary Science Through Paleontology, Sarah L. Sheffield, Jennifer E. Bauer Nov 2017

Darwin Day In Deep Time: Promoting Evolutionary Science Through Paleontology, Sarah L. Sheffield, Jennifer E. Bauer

School of Geosciences Faculty and Staff Publications

Charles Darwin’s birthday, February 12th, is an international celebration coined Darwin Day. During the week of his birthday, universities, museums, and science-oriented organizations worldwide host events that celebrate Darwin’s scientific achievements in evolutionary biology. The University of Tennessee, Knoxville (UT) has one of the longest running celebrations in the nation, with 2016 marking the 19th year. For 2016, the theme for our weeklong series of events was paleontology, chosen to celebrate new research in the field and to highlight the specific misconceptions of evolution within the context of geologic time. We provide insight into the workings of one of our …


Receiver Function Analyses Of Uturuncu Volcano, Bolivia And Vicinity, Heather Mcfarlin, Douglas Christensen, Stephen R. Mcnutt, Kevin M. Ward, Jamie Ryan, George Zandt, Glenn Thompson Nov 2017

Receiver Function Analyses Of Uturuncu Volcano, Bolivia And Vicinity, Heather Mcfarlin, Douglas Christensen, Stephen R. Mcnutt, Kevin M. Ward, Jamie Ryan, George Zandt, Glenn Thompson

School of Geosciences Faculty and Staff Publications

Uturuncu volcano, located near the borders of Chile and Bolivia in the Central Andes, has been identified as one of two volcanoes in the region with large-scale and active, yet decelerating, inflation. A large low-velocity zone named the Altiplano-Puna magma body (APMB) has been shown to feed magma to Uturuncu and is thought to be a source of the deformation occurring here. The international, multidisciplinary PLUTONS project deployed 28 broadband seismic sensors in a 90 km by 90 km region around and on Uturuncu volcano between April 2010 and October 2012. Over 800 teleseismic receiver functions have been generated and …


A Geophysical Model For The Origin Of Volcano Vent Clusters In A Colorado Plateau Volcanic Field, Fanghui Deng, Charles B. Connor, Rocco Malservisi, Laura J. Connor, Jeremy White, Aurélie Germa, Paul H. Wetmore Nov 2017

A Geophysical Model For The Origin Of Volcano Vent Clusters In A Colorado Plateau Volcanic Field, Fanghui Deng, Charles B. Connor, Rocco Malservisi, Laura J. Connor, Jeremy White, Aurélie Germa, Paul H. Wetmore

School of Geosciences Faculty and Staff Publications

Variation in spatial density of Quaternary volcanic vents, and the occurrence of vent clusters, correlates with boundaries in Proterozoic crust in the Springerville volcanic field (SVF), Arizona, USA. Inverse modeling using 538 gravity measurements shows that vent clusters correlate with gradients in the gravity field due to lateral variation in crustal density. These lateral discontinuities in the crustal density can be explained by boundaries in the North American crust formed during Proterozoic accretion. Spatial density of volcanic vents is low in regions of high‐density Proterozoic crust, high in areas of relatively low density Proterozoic crust, and is greatest adjacent to …


More Than Just Empty Space: Integrated Geoarchaeological Investigations Of The Crystal River Site (8ci1) Plaza, Alexander C. Delgado Oct 2017

More Than Just Empty Space: Integrated Geoarchaeological Investigations Of The Crystal River Site (8ci1) Plaza, Alexander C. Delgado

USF Tampa Graduate Theses and Dissertations

Crystal River (8CI1) is a Woodland period archaeological site on the west-central Gulf Coast of Florida, famous for its diverse suite of exotic artifacts typical of the Hopewell Interaction Sphere, as well as its monumental shell mounds which surround a central plaza. Historically, these plazas are utilized as spaces for cultural expression, daily interactions between members of the community, economic exchanges, and discourse of all types. They also serve as a symbolic space, embodying social and political relations that are critical to the formation and maintenance of cultural identity. These spaces are challenging to study using conventional archaeological techniques since …


Giovanni Badino (1953-2017), Arrigo Cigna, Paolo Forti Oct 2017

Giovanni Badino (1953-2017), Arrigo Cigna, Paolo Forti

International Journal of Speleology

Short obituary of Giovanni Badino.


Martian Cave Air-Movement Via Helmholtz Resonance, Kaj E. Williams, Timothy N. Titus, Chris H. Okubo, Glen E. Cushing Oct 2017

Martian Cave Air-Movement Via Helmholtz Resonance, Kaj E. Williams, Timothy N. Titus, Chris H. Okubo, Glen E. Cushing

International Journal of Speleology

Infrasonic resonance has previously been measured in terrestrial caves by other researchers, where Helmholtz resonance has been suggested as the plausible mechanism resulting in periodic wind reversals within cave entrances. We extend this reasoning to possible Martian caves, where we examine the characteristics of four atypical pit craters (APCs) on Tharsis, suggested as candidate cave entrance locations. The results show that, for several possible cave air movement periods, we are able to infer the approximate cave volumes. The utility of inferring cave volumes for planetary cave exploration is discussed.


Veress M., 2016. Covered Karsts, Reza Khoshraftar Sep 2017

Veress M., 2016. Covered Karsts, Reza Khoshraftar

International Journal of Speleology

No abstract provided.


Catchment-Scale Alder Cover Controls Nitrogen Fixation In Boreal Headwater Streams, Daniel L. Hiatt, Caleb J. Robbins, Jeffrey A. Back, Pamela K. Kostka, Robert D. Doyle, Coowe M. Walker, Mark C. Rains, Dennis F. Whigham, Ryan S. King Sep 2017

Catchment-Scale Alder Cover Controls Nitrogen Fixation In Boreal Headwater Streams, Daniel L. Hiatt, Caleb J. Robbins, Jeffrey A. Back, Pamela K. Kostka, Robert D. Doyle, Coowe M. Walker, Mark C. Rains, Dennis F. Whigham, Ryan S. King

School of Geosciences Faculty and Staff Publications

Alder (Alnus spp.) is a woody plant with bacterial symbionts that fix atmospheric N2into bioavailable N. We studied 12 North American boreal headwater streams spanning a steep gradient of catchment alder cover (0–27%) to test the hypothesis that increasing inputs of inorganic N associated with increasing alder cover would reduce or eliminate in-stream benthic N2 fixation. We measured N2 fixation rates, chlorophyll a, and ash-free dry mass (AFDM) of periphyton in early (May) and late (August) summer 2011. Dissolved inorganic N (DIN) concentrations, composed almost entirely of NO3/NO2-N, ranged from below detection limits to nearly 2 mg/L and …


Nuisance Flooding And Relative Sea-Level Rise: The Importance Of Present-Day Land Motion, Makan A. Karegar, Timothy H. Dixon, Rocco Malservisi, Jurgen Kusche, Simon E. Engelhart Sep 2017

Nuisance Flooding And Relative Sea-Level Rise: The Importance Of Present-Day Land Motion, Makan A. Karegar, Timothy H. Dixon, Rocco Malservisi, Jurgen Kusche, Simon E. Engelhart

School of Geosciences Faculty and Staff Publications

Sea-level rise is beginning to cause increased inundation of many low-lying coastal areas. While most of Earth’s coastal areas are at risk, areas that will be affected first are characterized by several additional factors. These include regional oceanographic and meteorological effects and/or land subsidence that cause relative sea level to rise faster than the global average. For catastrophic coastal flooding, when wind-driven storm surge inundates large areas, the relative contribution of sea-level rise to the frequency of these events is difficult to evaluate. For small scale “nuisance flooding,” often associated with high tides, recent increases in frequency are more clearly …


Antarctic Ice Sheet Slope And Aspect Based On Icesat's Repeat Orbit Measurement, L. Yuan, F. Li, S. Zhang, Surui Xie, F. Xiao, T. Zhu, Y. Zhang Sep 2017

Antarctic Ice Sheet Slope And Aspect Based On Icesat's Repeat Orbit Measurement, L. Yuan, F. Li, S. Zhang, Surui Xie, F. Xiao, T. Zhu, Y. Zhang

School of Geosciences Student Publications

Accurate information of ice sheet surface slope is essential for estimating elevation change by satellite altimetry measurement. A study is carried out to recover surface slope of Antarctic ice sheet from Ice, Cloud and land Elevation Satellite (ICESat) elevation measurements based on repeat orbits. ICESat provides repeat ground tracks within 200 meters in cross-track direction and 170 meters in along-track direction for most areas of Antarctic ice sheet. Both cross-track and along-track surface slopes could be obtained by adjacent repeat ground tracks. Combining those measurements yields a surface slope model with resolution of approximately 200 meters. An algorithm considering elevation …


Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. Van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan Aug 2017

Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. Van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan

International Journal of Speleology

In the mid-20th century, an inland brackish pond from Bermuda, known as Eve’s Pond, was filled with marine sediment from an adjacent coastal lagoon. At this time, an eyewitness reported “…sediment billowing out of the Green Bay Cave for days…”, which is a marine-dominated anchialine cave located proximal to the former location of Eve’s Pond (~200 m). The purpose of this study was to evaluate the potential impact of this infilling event on cave sedimentation and benthic meiofaunal communities, as proxied by the unicellular protists foraminifera that remain preserved in the sediment record. Eight sediment cores were collected from …


Differential Preservation Of Vertebrates In Southeast Asian Caves, Julien Louys, Shimona Kealy, Sue O'Connor, Gilbert J. Price, Stuart Hawkins, Ken Aplin, Yan Rizal, Jahdi Zaim, Mahirta, Daud A. Tanudirjo, Wahyu Dwijo Santoso, Ati Rati Hidayah, Agus Trihascaryo, Rachel Wood, Joseph Bevitt, Tara Clark Aug 2017

Differential Preservation Of Vertebrates In Southeast Asian Caves, Julien Louys, Shimona Kealy, Sue O'Connor, Gilbert J. Price, Stuart Hawkins, Ken Aplin, Yan Rizal, Jahdi Zaim, Mahirta, Daud A. Tanudirjo, Wahyu Dwijo Santoso, Ati Rati Hidayah, Agus Trihascaryo, Rachel Wood, Joseph Bevitt, Tara Clark

International Journal of Speleology

Caves have been an important source of vertebrate fossils for much of Southeast Asia, particularly for the Quaternary. Despite this importance, the mechanisms by which vertebrate remains accumulate and preserve in Southeast Asian caves has never been systematically reviewed or examined. Here, we present the results of three years of cave surveys in Indonesia and Timor-Leste, describing cave systems and their attendant vertebrate accumulations in diverse geological, biogeographical, and environmental settings. While each cave system is unique, we find that the accumulation and preservation of vertebrate remains are highly dependent on local geology and environment. These factors notwithstanding, we find …


The Significant Surface-Water Connectivity Of “Geographically Isolated Wetlands”, Aram J. K. Calhoun, David M. Mushet, Laurie C. Alexander, Edward S. Dekeyser, Laurie Fowler, Charles R. Lane, Megan W. Lang, Mark C. Rains, Stephen C. Richter, Susan C. Walls Aug 2017

The Significant Surface-Water Connectivity Of “Geographically Isolated Wetlands”, Aram J. K. Calhoun, David M. Mushet, Laurie C. Alexander, Edward S. Dekeyser, Laurie Fowler, Charles R. Lane, Megan W. Lang, Mark C. Rains, Stephen C. Richter, Susan C. Walls

School of Geosciences Faculty and Staff Publications

We evaluated the current literature, coupled with our collective research expertise, on surface-water connectivity of wetlands considered to be “geographically isolated” (sensu Tiner Wetlands 23:494–516, 2003a) to critically assess the scientific foundation of grouping wetlands based on the singular condition of being surrounded by uplands. The most recent research on wetlands considered to be “geographically isolated” shows the difficulties in grouping an ecological resource that does not reliably indicate lack of surface water connectivity in order to meet legal, regulatory, or scientific needs. Additionally, the practice of identifying “geographically isolated wetlands” based on distance from a stream can …


Acquisition Of A 3 Min, Two-Dimensional Glacier Velocity Field With Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, David M. Holland, Ryan Cassotto, Ian M. Howat, Mark A. Fahnestock, Martin Truffer, Santiago De La Pena Aug 2017

Acquisition Of A 3 Min, Two-Dimensional Glacier Velocity Field With Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, David M. Holland, Ryan Cassotto, Ian M. Howat, Mark A. Fahnestock, Martin Truffer, Santiago De La Pena

School of Geosciences Faculty and Staff Publications

Outlet glaciers undergo rapid spatial and temporal changes in flow velocity during calving events. Observing such changes requires both high temporal and high spatial resolution methods, something now possible with terrestrial radar interferometry. While a single such radar provides line-of-sight velocity, two radars define both components of the horizontal flow field. To assess the feasibility of obtaining the two-dimensional (2-D) flow field, we deployed two terrestrial radar interferometers at Jakobshavn Isbrae, a major outlet glacier on Greenland's west coast, in the summer of 2012. Here, we develop and demonstrate a method to combine the line-of-sight velocity data from two synchronized …


Mantle Dynamics Beneath The Discrete And Diffuse Plate Boundaries Of The Juan De Fuca Plate: Results From Cascadia Initiative Body Wave Tomography, Joseph S. Byrnes, Douglas R. Toomey, Emilie E. E. Hooft, John Nábělek, Jochen Braunmiller Aug 2017

Mantle Dynamics Beneath The Discrete And Diffuse Plate Boundaries Of The Juan De Fuca Plate: Results From Cascadia Initiative Body Wave Tomography, Joseph S. Byrnes, Douglas R. Toomey, Emilie E. E. Hooft, John Nábělek, Jochen Braunmiller

School of Geosciences Faculty and Staff Publications

We use the delay times of teleseismic S phases recorded by ocean bottom seismometers during the plate‐scale Cascadia Initiative community experiment to constrain the heterogeneity of seismic velocity structure beneath young oceanic lithosphere. Our study area covers the entire Juan de Fuca (JdF) and Gorda plates, from their creation at the JdF and Gorda Ridges to their subduction beneath the North American continent, and the entire length of the Blanco transform fault. The range of the observed Vs anomalies requires variations in the melt fraction of the asthenosphere. The data require that low Vsanomalies extend to depths of at …


Slow Slip Events In The Early Part Of The Earthquake Cycle, Nicholas K. Voss, Rocco Malservisi, Timothy H. Dixon, Marino Protti Aug 2017

Slow Slip Events In The Early Part Of The Earthquake Cycle, Nicholas K. Voss, Rocco Malservisi, Timothy H. Dixon, Marino Protti

School of Geosciences Faculty and Staff Publications

In February 2014 a Mw = 7.0 slow slip event (SSE) took place beneath the Nicoya Peninsula, Costa Rica. This event occurred 17 months after the 5 September 2012, Mw = 7.6, earthquake and along the same subduction zone segment, during a period when significant postseismic deformation was ongoing. A second SSE occurred in the middle of 2015, 21 months after the 2014 SSE and 38 months after the earthquake. The recurrence interval for Nicoya SSEs was unchanged by the earthquake. However, the spatial distribution of slip for the 2014 event differed significantly from previous events, having only …


Quantitative Literacy In The Affective Domain: Computational Geology Students’ Reactions To Devlin’S The Math Instinct, Victor J. Ricchezza, H. L. Vacher Jul 2017

Quantitative Literacy In The Affective Domain: Computational Geology Students’ Reactions To Devlin’S The Math Instinct, Victor J. Ricchezza, H. L. Vacher

Numeracy

Building on suggestions from alumni from a recent interview project, students in Computational Geology at the University of South Florida were tasked with reading a popular non-fiction book on mathematics and writing about the book and their feelings about math. The book, The Math Instinct by Keith Devlin, was chosen because we believed it would give the students something interesting to write about and not because we had any expectations in particular about what it might reveal about or do for their math anxiety. The nature of the responses received from the students led to the performance of a post-hoc …


Morphodynamics And Sediment Pathways Of The John's Pass-Blind Pass Dual-Inlet System: Pinellas County, Florida, Mark H. Horwitz Jul 2017

Morphodynamics And Sediment Pathways Of The John's Pass-Blind Pass Dual-Inlet System: Pinellas County, Florida, Mark H. Horwitz

USF Tampa Graduate Theses and Dissertations

The morphodynamics of an inlet channel draining an estuary or bay are governed by a complex system of temporally and spatially varying physical processes, including wind, waves, tides, sediment transport, and both tide and wave driven currents. In addition, sediment availability and characteristics in conjunction with underlying geologic framework bear on the morphology and morphologic behavior of an inlet system. This study examines the morphodynamics, sediment transport patterns and time-series morphologic change of John’s Pass and Blind Pass, two structured tidal inlets that collectively make up a dual-inlet system sharing the tidal prism of northern Boca Ciega Bay, in Pinellas …


Hydrogeology Of Salt Karst Under Different Cap Soils And Climates (Persian Gulf And Zagros Mts., Iran), Jiri Bruthans, Jiri Kamas, Michal Filippi, Mohammad Zare, Alan L. Mayo Jun 2017

Hydrogeology Of Salt Karst Under Different Cap Soils And Climates (Persian Gulf And Zagros Mts., Iran), Jiri Bruthans, Jiri Kamas, Michal Filippi, Mohammad Zare, Alan L. Mayo

International Journal of Speleology

Southern Iran hosts abundant salt karst phenomena in numerous salt diapirs. This paper provides a new insight into the relationships among climate, cap soil and salt karst hydrogeology. Cave systems were documented and mapped. Soil, drip, stream, and flood waters from different environments were studied at several diapirs. It was revealed that the soil water chemistry depends on both the climate and cap soil thickness. In semi-arid climates, a thick cap soil forms (>3 m) and water has very low TDS values (0.15 g/l). In arid climates, a shallow cap soil forms, and soil water is gypsum-saturated with low …