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Full-Text Articles in Physical Sciences and Mathematics

City Of Tampa Tree Canopy And Urban Forest Analysis 2021, Shawn M. Landry, Andrew K. Koeser, Rebecca Zarger, Kira Rib, Allyson Salisbury, Robert J. Northrop, Michael G. Andreu, Allison Bednar, Zach Freeman Feb 2023

City Of Tampa Tree Canopy And Urban Forest Analysis 2021, Shawn M. Landry, Andrew K. Koeser, Rebecca Zarger, Kira Rib, Allyson Salisbury, Robert J. Northrop, Michael G. Andreu, Allison Bednar, Zach Freeman

School of Geosciences Faculty and Staff Publications

This report summarizes the fourth tree canopy and urban forest analysis conducted for the City of Tampa and represents the year 2021. The City of Tampa tree ordinance (Ord. No. 2006-74, § 9, 3-23-06) requires an assessment of the tree canopy and urban forest every five years (beginning in 20061). In an effort to reduce concerns over bias, this work has been conducted by a collaborative team from the University of South Florida and the University of Florida following established USDA Forest Service protocols.

This report provides detailed information about the current size, composition, health, and distribution of Tampa’s urban …


Initial Estuarine Response To Inorganic Nutrient Inputs From A Legacy Mining Facility Adjacent To Tampa Bay, Florida, Marcus W. Beck, Andrew Altieri, Christine Angelini, Maya C. Burke, Jing Chen, Diana W. Chin, Jayne Gardiner, Chuanmin Hu, Katherine A. Hubbard, Yonggang Liu, Cary Lopez, Miles Medina, Elise Morrison, Edward J. Phlips, Gary E. Raulerson, Sheila Scolaro, Edward T. Sherwood, David Tomasko, Robert H. Weisberg, Joseph Whalen May 2022

Initial Estuarine Response To Inorganic Nutrient Inputs From A Legacy Mining Facility Adjacent To Tampa Bay, Florida, Marcus W. Beck, Andrew Altieri, Christine Angelini, Maya C. Burke, Jing Chen, Diana W. Chin, Jayne Gardiner, Chuanmin Hu, Katherine A. Hubbard, Yonggang Liu, Cary Lopez, Miles Medina, Elise Morrison, Edward J. Phlips, Gary E. Raulerson, Sheila Scolaro, Edward T. Sherwood, David Tomasko, Robert H. Weisberg, Joseph Whalen

Marine Science Faculty Publications

Legacy mining facilities pose significant risks to aquatic resources. From March 30th to April 9th, 2021, 814 million liters of phosphate mining wastewater and marine dredge water from the Piney Point facility were released into lower Tampa Bay (Florida, USA). This resulted in an estimated addition of 186 metric tons of total nitrogen, exceeding typical annual external nitrogen load estimates to lower Tampa Bay in a matter of days. An initial phytoplankton bloom (non-harmful diatoms) was first observed in April. Filamentous cyanobacteria blooms (Dapis spp.) peaked in June, followed by a bloom of the red tide organism Karenia brevis …


Using Remote Sensing And Machine Learning To Locate Groundwater Discharge To Salmon-Bearing Streams, Mary E. Gerlach, Kai C. Rains, Edgar J. Guerrón-Orejuela, William J. Kleindl, Joni Downs, Shawn M. Landry, Mark C. Rains Jan 2022

Using Remote Sensing And Machine Learning To Locate Groundwater Discharge To Salmon-Bearing Streams, Mary E. Gerlach, Kai C. Rains, Edgar J. Guerrón-Orejuela, William J. Kleindl, Joni Downs, Shawn M. Landry, Mark C. Rains

School of Geosciences Faculty and Staff Publications

We hypothesized topographic features alone could be used to locate groundwater discharge, but only where diagnostic topographic signatures could first be identified through the use of limited field observations and geologic data. We built a geodatabase from geologic and topographic data, with the geologic data only covering ~40% of the study area and topographic data derived from airborne LiDAR covering the entire study area. We identified two types of groundwater discharge: shallow hillslope groundwater discharge, commonly manifested as diffuse seeps, and aquifer-outcrop groundwater discharge, commonly manifested as springs. We developed multistep manual procedures that allowed us to accurately predict the …


Boron Isotopes In Boninites Document Rapid Changes In Slab Inputs During Subduction Initiation, Hong-Yan Li, Xiang Li, Jeffrey G. Ryan, Chao Zhang, Yi-Gang Xu Jan 2022

Boron Isotopes In Boninites Document Rapid Changes In Slab Inputs During Subduction Initiation, Hong-Yan Li, Xiang Li, Jeffrey G. Ryan, Chao Zhang, Yi-Gang Xu

School of Geosciences Faculty and Staff Publications

How subduction-related magmatism starts at convergent plate margins is still poorly understood. Here we show that boron isotope variations in early-formed boninites from the Izu-Bonin arc, combined with radiogenic isotopes and elemental ratios document rapid (~0.5 to 1 Myr) changes in the sources and makeup of slab inputs as subduction begins. Heterogeneous hornblende-granulite facies melts from ocean crust gabbros ± basalts fluxed early melting to generate low silica boninites. Hydrous fluids from slab sediments and basalts later fluxed the low silica boninites mantle source to produce high silica boninites. Our results suggest that initially the uppermost parts of the slab …


Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin Jan 2022

Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin

School of Geosciences Faculty and Staff Publications

Uncertainty quantification (UQ) in eruption source parameters, like tephra volume, plume height, and umbrella cloud radius, is a challenge for volcano scientists because tephra deposits are often sparsely sampled due to burial, erosion, and related factors. We find that UQ is improved by coupling an advection-diffusion model with two Bayesian inversion approaches: (a) a robust but computationally expensive Generalized Likelihood Uncertainty Estimation algorithm, and (b) a more approximate but inexpensive parameter estimation algorithm combined with first-order, second-moment uncertainty estimation. We apply the two inversion methods to one sparsely sampled tephra fall unit from the 2070 BP El Misti (Peru) eruption …


Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha’Apai Volcano Provide An Excellent Research Opportunity, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka Jan 2022

Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha’Apai Volcano Provide An Excellent Research Opportunity, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka

School of Geosciences Faculty and Staff Publications

We present a narrative of the eruptive events culminating in the cataclysmic 15 January 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and lightning data available within the first few weeks after the eruption occurred. The first hour of eruptive activity produced fast-propagating tsunami waves, long-period seismic waves, loud audible sound waves, infrasonic waves, exceptionally intense volcanic lightning and an unsteady volcanic plume that transiently reached—at 58 km—the Earth’s mesosphere. Energetic seismic signals were recorded worldwide and the globally stacked seismogram showed episodic seismic events within the most intense periods of phreatoplinian activity, …


Spatial Variation Of Subduction Zone Fluids During Progressive Subduction: Insights From Serpentinite Mud Volcanoes, Catriona D. Menzies, Roy E. Price, Jeffrey Ryan, Olivier Sissmann, Ken Takai, C. Geoffrey Wheat Jan 2022

Spatial Variation Of Subduction Zone Fluids During Progressive Subduction: Insights From Serpentinite Mud Volcanoes, Catriona D. Menzies, Roy E. Price, Jeffrey Ryan, Olivier Sissmann, Ken Takai, C. Geoffrey Wheat

School of Geosciences Faculty and Staff Publications

Geological processes at subduction zones control seismicity, plutonism and volcanism, and geochemical cycling between the oceans, crust, and mantle. The down-going plate experiences metamorphism, and the associated dehydration and fluid flow alters the physical properties of the plate interface and mantle wedge, as well as controlling the composition of material descending into the mantle. Any direct study of slab evolution during subduction is inhibited by the prohibitive depths at which these processes occur. To examine these processes we use serpentinite mud volcanoes in the Mariana forearc, that permit sampling of serpentinite materials and their pore waters that …


Relationship Between Dike Injection And B-Value For Volcanic Earthquake Swarms, Allen F. Glazner, Stephen R. Mcnutt Dec 2021

Relationship Between Dike Injection And B-Value For Volcanic Earthquake Swarms, Allen F. Glazner, Stephen R. Mcnutt

School of Geosciences Faculty and Staff Publications

Dike swarms are the fossil remains of regions of the crust that have undergone repeated magma injections. Volcanic earthquake swarms and geodetic measurements are, at least in part, a record of active injection of fluids (water, gas, or magma) into fractures. Here, we link these two ways of observing magmatic systems by noting that dike thicknesses and earthquake magnitudes share similar scaling parameters. In the Jurassic Independence dike swarm of eastern California median dike thickness is ∼1 m, similar to other swarms worldwide, but glacially polished exposures reveal that a typical dike comprises a number of dikelets that are lognormally …


Monochromatic Long-Period Seismicity Prior To The 2012 Earthquake Swarm At Little Sitkin Volcano, Alaska, Matthew M. Haney, Helena Buurman, Stephen Holtkamp, Stephen R. Mcnutt Jan 2021

Monochromatic Long-Period Seismicity Prior To The 2012 Earthquake Swarm At Little Sitkin Volcano, Alaska, Matthew M. Haney, Helena Buurman, Stephen Holtkamp, Stephen R. Mcnutt

School of Geosciences Faculty and Staff Publications

Detection of the earliest stages of unrest is one of the most challenging and yet critically needed aspects of volcano monitoring. We investigate a sequence of five unusual long-period (LP) earthquakes that occurred in the days prior to the onset of a months-long volcano-tectonic (VT) earthquake swarm beneath Little Sitkin volcano in the Aleutian Islands during late 2012. The long-period earthquakes had two distinctive characteristics: their signals were dominated by a monochromatic spectral peak at approximately 0.57 Hz and they had impulsive P and S-wave arrivals on a seismometer located on Amchitka Island 80 km to the southeast of the …


Exploring Best Practices In Geoscience Education: Adapting A Video/Animation On Continental Rifting For Upper-Division Students To A Lower-Division Audience, Siloa Willis, Robert J. Stern, Jeffrey Ryan, Christy Bebeau Jan 2021

Exploring Best Practices In Geoscience Education: Adapting A Video/Animation On Continental Rifting For Upper-Division Students To A Lower-Division Audience, Siloa Willis, Robert J. Stern, Jeffrey Ryan, Christy Bebeau

School of Geosciences Faculty and Staff Publications

Well-crafted and scientifically accurate videos and animations can be effective ways to teach dynamic Earth processes such as continental rifting, both in live course offerings as well as in online settings. However, a quick search of the internet reveals too few high-quality videos/animations describing deep Earth processes. We have modified a hybrid 10.5 min video/animation about continental rifting and the formation of new oceans and passive continental margins created for an upper-division geology audience, retailoring it for a lower-division geology audience. A key challenge in successfully modifying such resources is aligning the cognitive load that the video/animation imposes on students, …


The Radius Of The Umbrella Cloud Helps Characterize Large Explosive Volcanic Eruptions, Robert Constantinescu, Aurelian Hopulele-Gligor, Charles Connor, Costanza Bonadonna, Laura Connor, Jan Lindsay, Sylvain Charbonnier, Alain C.M. Volentik Jan 2021

The Radius Of The Umbrella Cloud Helps Characterize Large Explosive Volcanic Eruptions, Robert Constantinescu, Aurelian Hopulele-Gligor, Charles Connor, Costanza Bonadonna, Laura Connor, Jan Lindsay, Sylvain Charbonnier, Alain C.M. Volentik

School of Geosciences Faculty and Staff Publications

Eruption source parameters (in particular erupted volume and column height) are used by volcanologists to inform volcanic hazard assessments and to classify explosive volcanic eruptions. Estimations of source parameters are associated with large uncertainties due to various factors, including complex tephra sedimentation patterns from gravitationally spreading umbrella clouds. We modify an advection-diffusion model to investigate this effect. Using this model, source parameters for the climactic phase of the 2450 BP eruption of Pululagua, Ecuador, are different with respect to previous estimates (erupted mass: 1.5–5 × 1011 kg, umbrella cloud radius: 10–14 km, plume height: 20–30 km). We suggest large …


Adequately Reflecting The Severity Of Tropical Cyclones Using The New Tropical Cyclone Severity Scale, Nadia Bloemendaal, Hans De Moel, Jantsje M. Mol, Priscilla R.M. Bosma, Amy Polen, Jennifer M. Collins Jan 2021

Adequately Reflecting The Severity Of Tropical Cyclones Using The New Tropical Cyclone Severity Scale, Nadia Bloemendaal, Hans De Moel, Jantsje M. Mol, Priscilla R.M. Bosma, Amy Polen, Jennifer M. Collins

School of Geosciences Faculty and Staff Publications

For decades, meteorologists and governments have been warning communities in coastal areas for an imminent tropical cyclone (TC) using the Saffir-Simpson Hurricane Wind Scale (SSHWS). The SSHWS categorizes a TC based on its maximum wind speed, and is used in defining evacuation strategies and humanitarian response. However, the SSHWS considers only the wind hazard of a TC, whereas a TC can also cause severe conditions through its high storm surges and extreme rainfall, triggering coastal and inland flooding. Consequently, the SSHWS fails to mirror the TC's total severity. This becomes evident when looking at past events such as Hurricane Harvey …


Formation Mechanisms Of Macroscopic Globules In Andesitic Glasses From The Izu–Bonin–Mariana Forearc (Iodp Expedition 352), Raúl O.C. Fonseca, Lina T. Michely, Maria Kirchenbaur, Julie Prytulak, Jeffrey Ryan, Kerstin Hauke, Felipe P. Leitzke, Renat R. Almeev, Chris S. Marien, Axel Gerdes, Rico Schellhorn Jan 2021

Formation Mechanisms Of Macroscopic Globules In Andesitic Glasses From The Izu–Bonin–Mariana Forearc (Iodp Expedition 352), Raúl O.C. Fonseca, Lina T. Michely, Maria Kirchenbaur, Julie Prytulak, Jeffrey Ryan, Kerstin Hauke, Felipe P. Leitzke, Renat R. Almeev, Chris S. Marien, Axel Gerdes, Rico Schellhorn

School of Geosciences Faculty and Staff Publications

The Izu–Bonin–Mariana volcanic arc is situated at a convergent plate margin where subduction initiation triggered the formation of MORB-like forearc basalts as a result of decompression melting and near-trench spreading. International Ocean Discovery Program (IODP) Expedition 352 recovered samples within the forearc basalt stratigraphy that contained unusual macroscopic globular textures hosted in andesitic glass (Unit 6, Hole 1440B). It is unclear how these andesites, which are unique in a stratigraphic sequence dominated by forearc basalts, and the globular textures therein may have formed. Here, we present detailed textural evidence, major and trace element analysis, as well as B and Sr …


Magma Source Evolution Following Subduction Initiation: Evidence From The Element Concentrations, Stable Isotope Ratios, And Water Contents Of Volcanic Glasses From The Bonin Forearc (Iodp Expedition 352), Daniel A. Coulthard, Mark K. Reagan, Kenji Shimizu, Ilya N. Bindeman, Maryjo Brounce, Renat R. Almeev, Jeffrey Ryan, Timothy Chapman, John Shervais, Julian A. Pearce Jan 2021

Magma Source Evolution Following Subduction Initiation: Evidence From The Element Concentrations, Stable Isotope Ratios, And Water Contents Of Volcanic Glasses From The Bonin Forearc (Iodp Expedition 352), Daniel A. Coulthard, Mark K. Reagan, Kenji Shimizu, Ilya N. Bindeman, Maryjo Brounce, Renat R. Almeev, Jeffrey Ryan, Timothy Chapman, John Shervais, Julian A. Pearce

School of Geosciences Faculty and Staff Publications

International Ocean Discovery Program Expedition 352 to the Bonin forearc drilled the sequence of volcanic rocks erupted in the immediate aftermath of subduction initiation along the western margin of the Pacific Plate. Pristine volcanic glasses collected during this expedition were analyzed for major and trace elements, halogens, sulfur, and H and O isotopes with goals of characterizing the fluids and melts of subducted materials that were involved in generating the nascent upper plate crust. Incompatible trace element compositions of the oldest lavas (forearc basalts [FAB]) are similar to those of the most depleted mid‐ocean ridge basalts globally. Most FAB were …


Linking Landscape Attributes To Salmon And Decision-Making In The Southern Kenai Lowlands, Alaska, Usa, Coowe M. Walker, Dennis F. Whigham, I. Syverine Bentz, Jacob M. Argueta, Ryan S. King, Mark C. Rains, Charles A. Simenstad, Chris Guo, Steven J. Baird, Conrad J. Field Jan 2021

Linking Landscape Attributes To Salmon And Decision-Making In The Southern Kenai Lowlands, Alaska, Usa, Coowe M. Walker, Dennis F. Whigham, I. Syverine Bentz, Jacob M. Argueta, Ryan S. King, Mark C. Rains, Charles A. Simenstad, Chris Guo, Steven J. Baird, Conrad J. Field

School of Geosciences Faculty and Staff Publications

While Pacific salmon are economically and culturally important worldwide, Alaska, USA is one of the few remaining places on earth where sustainable management of salmon is possible, even in the face of wide-ranging threats, including overharvesting and the impacts of climate change. A continuing challenge that we face is to understand the ecological processes that result in sustainable salmon populations and report that science to stakeholders in a way that promotes decision-making to avoid the destruction of salmon populations that has occurred in most areas of the lower 48 states. To address this challenge, our studies in the southern Kenai …


Perceptions Of Scientists Held By Us Students Can Be Broadened Through Inclusive Classroom Interventions, Sarah L. Sheffield, Meghan L. Cook, Victor J. Ricchezza, Guizella A. Rocabado, Fenda A. Akiwumi Jan 2021

Perceptions Of Scientists Held By Us Students Can Be Broadened Through Inclusive Classroom Interventions, Sarah L. Sheffield, Meghan L. Cook, Victor J. Ricchezza, Guizella A. Rocabado, Fenda A. Akiwumi

School of Geosciences Faculty and Staff Publications

More diverse representation in undergraduate classrooms may be an important step towards turning science, technology, engineering, and mathematics (STEM) disciplines into more inclusive communities. In the United States of America, the individuals whose work is discussed in typical introductory science courses collectively do not represent the diversity of students’ identities in the classroom and further reinforce existing stereotypes of scientists as male, white, and aged. Here we report on the implementation of a semester-long intervention in an introductory-level geoscience course at the University of South Florida, USA. We introduced students to individuals with marginalized identities who are either scientists or …


Ethical Product Havens In The Global Diamond Trade: Using The Wayback Machine To Evaluate Ethical Market Outcomes, Trina Hamilton, Seth Cavello Jan 2021

Ethical Product Havens In The Global Diamond Trade: Using The Wayback Machine To Evaluate Ethical Market Outcomes, Trina Hamilton, Seth Cavello

School of Geosciences Faculty and Staff Publications

Who benefits from ethical product markets? While most ethical products (e.g. fair trade and eco-certified products) are intended to benefit marginalized communities and vulnerable ecosystems, the reality is that the geographic preferences exhibited by so-called ethical markets may, in fact, reinforce global inequities rather than remedy them. It can be difficult to evaluate the outcomes of ethical product markets, however, because we are often limited to data from a small number of industries with widely used standards and certifications. This research pilots a new methodology, using an online archive—the Wayback Machine, to evaluate shifts in countries' ethical market share, focusing …


Magmatic Response To Subduction Initiation, Part Ii: Boninites And Related Rocks Of The Izu‐Bonin Arc From Iopd Expedition 352, John W. Shervais, Mark K. Reagan, Marguerite Godard, Julie Prytulak, Jeffrey G. Ryan Jan 2021

Magmatic Response To Subduction Initiation, Part Ii: Boninites And Related Rocks Of The Izu‐Bonin Arc From Iopd Expedition 352, John W. Shervais, Mark K. Reagan, Marguerite Godard, Julie Prytulak, Jeffrey G. Ryan

School of Geosciences Faculty and Staff Publications

International Ocean Discovery Program Expedition 352 to the Izu‐Bonin forearc cored over 800 m of basement comprising boninite and boninite‐series lavas. This is the most extensive, well‐constrained suite of boninite series lavas ever obtained from in situ oceanic crust. The boninites are characterized as high‐silica boninite (HSB), low‐silica boninite (LSB), or basaltic boninite based on their SiO2‐MgO‐TiO2 relations. The principal fractionation products of all three series are high‐Mg andesites (HMA). Lavas recovered >250 meters below seafloor (mbsf) erupted at a forearc spreading axis and are dominated by LSB and HMA. Lavas recovered fromoff‐axis and are dominated by …


Impulsive Volcanic Plumes Generate Volcanic Lightning And Vent Discharges: A Statistical Analysis Of Sakurajima Volcano In 2015, Cassandra M. Smith, Damien Gaudin, Alexa R. Van Eaton, Sonja A. Behnke, Steven Reader, Ronald J. Thomas, Harald Edens, Stephen R. Mcnutt, Corrado Cimarelli Jan 2021

Impulsive Volcanic Plumes Generate Volcanic Lightning And Vent Discharges: A Statistical Analysis Of Sakurajima Volcano In 2015, Cassandra M. Smith, Damien Gaudin, Alexa R. Van Eaton, Sonja A. Behnke, Steven Reader, Ronald J. Thomas, Harald Edens, Stephen R. Mcnutt, Corrado Cimarelli

School of Geosciences Faculty and Staff Publications

The origin of electrical activity accompanying volcanic ash plumes is an area of heightened interest in volcanology. However, it is unclear how intense an eruption needs to be to produce lightning flashes as opposed to “vent discharges,” which represent the smallest scale of electrical activity. This study targets 97 carefully monitored plumesJapan, from June 1 to 7, 2015. We use multiparametric measurements from sensors including a nine-station lightning mapping array and an infrared camera to characterize plume ascent. Findings demonstrate that the impulsive, high velocity plumes (>55 m/s) were most likely to create vent discharges, whereas lightning flashes occurred …


Molybdenum Isotopes Unmask Slab Dehydration And Melting Beneath The Mariana Arc, Hong-Yan Li, Rui-Peng Zhao, Jie Li, Yoshihiko Tamura, Christopher Spencer, Robert J. Stern, Jeffrey G. Ryan, Yi-Gang Xu Jan 2021

Molybdenum Isotopes Unmask Slab Dehydration And Melting Beneath The Mariana Arc, Hong-Yan Li, Rui-Peng Zhao, Jie Li, Yoshihiko Tamura, Christopher Spencer, Robert J. Stern, Jeffrey G. Ryan, Yi-Gang Xu

School of Geosciences Faculty and Staff Publications

How serpentinites in the forearc mantle and subducted lithosphere become involved in enriching the subarc mantle source of arc magmas is controversial. Here we report molybdenum isotopes for primitive submarine lavas and serpentinites from active volcanoes and serpentinite mud volcanoes in the Mariana arc. These data, in combination with radiogenic isotopes and elemental ratios, allow development of a model whereby shallow, partially serpentinized and subducted forearc mantle transfers fluid and melt from the subducted slab into the subarc mantle. These entrained forearc mantle fragments are further metasomatized by slab fluids/melts derived from the dehydration of serpentinites in the subducted lithospheric …


Large-Volume And Shallow Magma Intrusions In The Blackfoot Reservoir Volcanic Field (Idaho, Usa), M. S. Hastings, C. B. Connor, P. Wetmore, R. Malservisi, L. J. Connor, M. Rodgers, P. C. Femina Jan 2021

Large-Volume And Shallow Magma Intrusions In The Blackfoot Reservoir Volcanic Field (Idaho, Usa), M. S. Hastings, C. B. Connor, P. Wetmore, R. Malservisi, L. J. Connor, M. Rodgers, P. C. Femina

School of Geosciences Faculty and Staff Publications

he Blackfoot Reservoir volcanic field (BRVF), Idaho, USA, is a bimodal volcanic field that has hosted silicic eruptions during at least two episodes, as recently as 58 ka. Using newly collected ground and boat-based gravity data, two large negative anomalies (-16 mGal) are modeled as shallow (< 1  km) intrusions beneath a NE-trending alignment of BRVF rhyolite domes and tuff rings. Given the trade-off between density contrast and model volume, best-fit gravity inversion models yield a total intrusion volume of 50-120 km3; a density contrast of -400 kg m-3 results in two intrusions, each ~9 km x 4.5 km and about 0.5 km thick, with cumulative volume of 100 km3. A network of 340°-360° trending faults lies directly above and on the margins of the mapped gravity anomalies. Most of …


Dynamically Weighted Balanced Loss: Class Imbalanced Learning And Confidence Calibration Of Deep Neural Networks, K. Ruwani M. Fernando, Chris P. Tsokos Jan 2021

Dynamically Weighted Balanced Loss: Class Imbalanced Learning And Confidence Calibration Of Deep Neural Networks, K. Ruwani M. Fernando, Chris P. Tsokos

Mathematics and Statistics Faculty Publications

Imbalanced class distribution is an inherent problem in many real-world classification tasks where the minority class is the class of interest. Many conventional statistical and machine learning classification algorithms are subject to frequency bias, and learning discriminating boundaries between the minority and majority classes could be challenging. To address the class distribution imbalance in deep learning, we propose a class rebalancing strategy based on a class-balanced dynamically weighted loss function where weights are assigned based on the class frequency and predicted probability of ground-truth class. The ability of dynamic weighting scheme to self-adapt its weights depending on the prediction scores …


A Preliminary Exploration Of The Cooling Effect Of Tree Shade In Urban Landscapes, Qiuyan Yu, Wenjie Ji, Ruiliang Pu, Shawn Landry, Michael Acheampong, Jarlath O'Neil-Dunne, Zhibin Ren, Shakhawat H. Tanim Oct 2020

A Preliminary Exploration Of The Cooling Effect Of Tree Shade In Urban Landscapes, Qiuyan Yu, Wenjie Ji, Ruiliang Pu, Shawn Landry, Michael Acheampong, Jarlath O'Neil-Dunne, Zhibin Ren, Shakhawat H. Tanim

School of Geosciences Faculty and Staff Publications

Mitigating urban heat island (UHI) effects, especially under climate change, is necessary for the promotion of urban sustainability. Shade is one of the most important functions provided by urban trees for mitigating UHI. However, the cooling effect of tree shade has not been adequately investigated. In this study, we used a simple and straightforward method to quantify the spatial and temporal variation of tree shade and examined its effect on land surface temperature (LST). We used the hillshade function in a geographic information system to quantify the spatiotemporal patterns of tree shade by integrating sun location and tree height. Relationships …


Examining The Statistical Relationships Between Volcanic Seismic, Infrasound, And Electrical Signals: A Case Study Of Sakurajima Volcano, 2015, Cassandra M. Smith, Glenn Thompson, Steven Reader, Sonja A. Behnke, Stephen R. Mcnutt, Ron Thomas, Harald Edens Sep 2020

Examining The Statistical Relationships Between Volcanic Seismic, Infrasound, And Electrical Signals: A Case Study Of Sakurajima Volcano, 2015, Cassandra M. Smith, Glenn Thompson, Steven Reader, Sonja A. Behnke, Stephen R. Mcnutt, Ron Thomas, Harald Edens

School of Geosciences Faculty and Staff Publications

Sakurajima volcano in Japan is known for frequent eruptions containing prolific volcanic lightning. Previous studies from eruptions at Redoubt have shown preliminary correlations between seismic, infrasound, and radio frequency signals. This study uses field data collected at Sakurajima from 28 May–7 June 2015 and multivariable statistical modeling to quantify these relationships. We build regression equations to examine each of the following parameters of electrical activity: (1) the presence of electrical activity, (2) the presence of the radio frequency signal called continual radio frequency impulses (CRF), (3) the presence of lightning, (4) the overall duration of electrical activity, and (5) the …


Geophysical And Social Influences On Evacuation Decision-Making: The Case Of Hurricane Irma, Robin Ersing, Christianne Pearce, Jennifer M. Collins, Michelle E. Saunders, Amy Polen Aug 2020

Geophysical And Social Influences On Evacuation Decision-Making: The Case Of Hurricane Irma, Robin Ersing, Christianne Pearce, Jennifer M. Collins, Michelle E. Saunders, Amy Polen

School of Geosciences Faculty and Staff Publications

Understanding the factors that influence evacuation decision-making among local residents is of critical importance to those involved in monitoring and managing weather-related hazards. This study examined both geophysical and social variables that we believe influenced individual decision-making on whether to stay home, seek out a public shelter, or leave the area entirely during Hurricane Irma. A 23-item survey was administered to a convenience sample of adults (n = 234) who resided within a coastal Florida county that received an evacuation warning during Hurricane Irma in 2017. Results suggested sources of information relied on through media, government, family, and social networks …


Dynamics And Impacts Of The May 8th, 1902 Pyroclastic Current At Mount Pelée (Martinique): New Insights From Numerical Modeling, Valentin Gueugneau, Karim Kelfoun, Sylvain J. Charbonnier, Aurelie Germa, Guillaume Carazzo Jul 2020

Dynamics And Impacts Of The May 8th, 1902 Pyroclastic Current At Mount Pelée (Martinique): New Insights From Numerical Modeling, Valentin Gueugneau, Karim Kelfoun, Sylvain J. Charbonnier, Aurelie Germa, Guillaume Carazzo

School of Geosciences Faculty and Staff Publications

The Mount Pelée May 8th, 1902 eruption is responsible for the deaths of more than 29,000 people, as well as the nearly-complete destruction of the city of Saint Pierre by a single pyroclastic current, and is, sadly, the deadliest eruption of the 20th century. Despite intensive field studies on the associated deposit, two conflicting interpretations of the pyroclastic current dynamics (either a blast or a simple ash-cloud surge) emerged in the 90’s and have been paralyzing research ever since, leaving numerous unknowns (i.e., source conditions, volume). This study is the first to investigate numerically the May 8th, 1902 pyroclastic …


Pystprism: Tools For Voxel-Based Space–Time Prisms, Rebecca Loraamm, Joni A. Downs, James Anderson, David S. Lamb Jul 2020

Pystprism: Tools For Voxel-Based Space–Time Prisms, Rebecca Loraamm, Joni A. Downs, James Anderson, David S. Lamb

School of Geosciences Faculty and Staff Publications

The observed movements of humans and animals are realizations of complex spatiotemporal processes. Recent advances in location-aware technologies have rendered trajectory data ubiquitous. Examining the sequenced, instantaneous locations found in movement trajectory data for information reconstructing the location or state of the mover between observed points comprises a primary focus in Time Geography and related disciplines. The PySTPrism toolbox introduced in this paper provides a straightforward and open-source implementation of the Probabilistic Space Time Prism, in addition to related tools from Time Geography. PySTPrism is implemented in Python using the ArcPy module in ArcGIS Pro Desktop.


Novel Quantification Of Shallow Sediment Compaction By Gps Interferometric Reflectometry And Implications For Flood Susceptibility, Makan A. Karegar, Kristine M. Larson, Jurgen Kusche, Timothy H. Dixon Jul 2020

Novel Quantification Of Shallow Sediment Compaction By Gps Interferometric Reflectometry And Implications For Flood Susceptibility, Makan A. Karegar, Kristine M. Larson, Jurgen Kusche, Timothy H. Dixon

School of Geosciences Faculty and Staff Publications

Estimates of flood susceptibility and land loss in the world's coastal regions depend on our knowledge of sea level rise (SLR) from increases in ocean mass and volume, as well as knowledge of vertical land motion. Conventional approaches to the latter include tide‐gauge and Global Positioning System (GPS) measurements relative to well‐anchored monuments few meters below the surface. However, in regions of rapid Holocene sedimentation, compaction of this material can add a significant component to the surface lowering. Unfortunately, this process has been difficult to quantify, especially for the shallowest material above the monument. Here we use a new technique, …


Resolution Of Lava Tubes With Ground Penetrating Radar: The Tubex Project, Sanaz Esmaeili, Sarah Kruse, Sajad Jazayeri, P. Whelley, E. Bell, J. Richardson, W. B. Garry, K. Young May 2020

Resolution Of Lava Tubes With Ground Penetrating Radar: The Tubex Project, Sanaz Esmaeili, Sarah Kruse, Sajad Jazayeri, P. Whelley, E. Bell, J. Richardson, W. B. Garry, K. Young

School of Geosciences Faculty and Staff Publications

Remote sensing surveys of the Moon and Mars show evidence of lava tubes, which are potential safe havens for human crews and their equipment. Ground penetrating radar (GPR) can be used to map tubes because the void/rock interface at tube ceilings and floors strongly reflects radar pulses. We have tested the capacity of GPR to sense lava tube geometry at Lava Beds National Monument in California, USA. GPR and detailed light detection and ranging (LiDAR) data are presented for two tubes: Skull Cave, with a few meters of overburden, diameter ~10–20 m, and a rubbly floor; and Valentine Cave, with …


Biogenic Silica And Organic Carbon Records In Zhoushan Coastal Sea Over The Past One Hundred Years And Their Environmental Indications, Hao Xu, Shangwei Jiang, Jialin Li, Ruiliang Pu, Jia Wang, Wanghai Jin, Longbin Sha, Dongling Li May 2020

Biogenic Silica And Organic Carbon Records In Zhoushan Coastal Sea Over The Past One Hundred Years And Their Environmental Indications, Hao Xu, Shangwei Jiang, Jialin Li, Ruiliang Pu, Jia Wang, Wanghai Jin, Longbin Sha, Dongling Li

School of Geosciences Faculty and Staff Publications

The influence of terrestrial and marine input has dramatically changed eutrophication in coastal seas over the past 100 years. In this study, Zhoushan coastal sea (ZCS) is taken as a study area. We studied ZCS as it is a sink of the temporal and spatial variation of primary productivity, dominant species of algae, and the variation of provenance in this area over the past 100 years. We performed analysis using three sediment cores and the carbon and silicon deposition records. The analysis results demonstrate that: (1) The primary productivity in the northern area of the ZCS close to the Yangtze …