Geology Commons^™

Studying Redox Conditions Of Devonian And Neoproterozoic Oceans Using I/Ca Proxy From Bulk Carbonate Rocks, Ruliang He

Dissertations - ALL

Iodine is an important trace element in biogeochemical and redox reactions. It has a nearly consistent concentration of ~0.46 μmol/L in the seawater and the inorganic speciation (IO3− and I−) of iodine is primarily controlled by redox conditions in water columns. Iodate (IO3−), not iodide (I−), is the only species that can be incorporated into carbonate minerals. Therefore, I/Ca ratio from carbonate rocks can be used to constrain the redox condition in the water column over a range of time scale. This dissertation contains three chapters that utilizes I/Ca ratio from bulk carbonate rocks to reconstruct ocean redox changes during …

An Assessment Of The Performance Of The Earthscope Automated Receiver Survey: A User’S Guide To Ears., Erin L. Taxon

Theses and Dissertations

An Assessment of the Performance of the EarthScope Automatic Receiver Survey: A User's Guide to EARS.

With the advent of digital seismic recording, the ability to process and interpret large quantities of seismic data has become increasingly vital. EarthScope Automated Receiver Survey, EARS, was launched in 2005 to estimate bulk crustal properties in real time, at all broadband seismograph stations, globally. EARS utilizes the receiver function HK stacking method to estimate a station’s crustal thickness (H) and ratio of P wave velocity (Vp) and S wave velocity (Vs), known as Vp/Vs (K). Receiver function analysis observes the arrival times …

Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi

Tanzania Journal of Science

This study aimed at evaluating natural radioactivity and radiation hazards of soils around a petroleum product marketing company due to anthropogenic influences using gamma ray spectrometry. Top soils (5 cm deep) were collected from diverse locations inside the premises of the Company using standard analytical technique, while control samples were acquired at approximately 200 m from the study area. Mean activity concentrations of the radionuclides in the test soils were 89.36 Bq/kg for 40K, 92.1 Bq/kg for 238U and 10.95 Bq/kg for 232Th, which are more than that of control samples with statistically significant differences. Assessment of the radiological levels …

Charcoal Whirlwinds And Post-Fire Observations In Serengeti National Park Savannahs, Colin J. Courtney Mustaphi, Heleen C. Vos, Rob Marchant, Colin Beale

Tanzania Journal of Science

Whirlwinds and visible dust devils occur over semi-arid ecosystems and entrain particles from the ground surface. Fires produce abundant charcoal across savannahs and the resulting blackened surfaces create a large albedo contrast. Whirlwinds have been observed associated with active fires; yet, there are few published observations on post-fire landscapes. Spatiotemporal patterns of whirlwinds have been documented for a limited number of regions and have not been made for the ecosystems of eastern Africa. From field-based sightings in the Serengeti National Park, Tanzania, we report on whirlwinds over burned savannah patches that entrained large quantities of charcoal to produce black coloured …

Characterization Of Clay And Granite Dust Blends As Novel Materials For Energy Storage And Diffuser In Constructing Flat-Plate Solar Collector, Tajudeen Kolawole Ajiboye, Mustapha Olawale Fabiyi, Ndagi Mustapha, Sulaiman Abdulkareem

Tanzania Journal of Science

Sun is the main source of solar energy, and the energy it releases to the Earth’s surface in one hour is more than what the whole planet consumes in a year. This present work is about characterizing novel material that can be used as energy storage and diffuser in constructing flat plate solar collector. Materials used are clay and granite dust obtained from Okelele and Kulende Quarry sites, both in Ilorin, Kwara State, Nigeria. The materials were sun-dried; the clay crushed before the two materials were sieved into different particle sizes. They were thereafter blended into different ratios and then …

Sedimentary Characteristics And Associated Carbon And Nutrients Of Overbank Sediments Deposited During The 2018, 2019, And 2020 Floods In Embanked Floodplains Along The Lower Mississippi River Near Natchez, Mississippi, Rachel Kelk

Master's Theses

The Lower Mississippi River (LMR) experienced major floods in 2018, 2019, and 2020. Sediment deposition in the embanked floodplains during floods represent important storage and sequestration opportunities for carbon and nutrients from ~40% of the continental USA. This research aims to compare depositional thicknesses, organic matter (OM), carbon (C), nitrogen (N), phosphorous (P) concentrations, and grain sizes in floodplain sediments deposited by the combined 2018-19 floods to the 2020 flood along the LMR near Natchez, Mississippi. Greater depositional thicknesses in 2018-19 are best explained by their combined flood durations; the 2019 flood was the longest in recorded history. Slightly higher …

Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins

USF Tampa Graduate Theses and Dissertations

The Southwest of the United States is currently in a megadrought phase. Recent studies have shown that three of the most severe droughts of the last two millennia have occurred in the last 120 years, while geo-archaeological evidence suggests there were five megadroughts just from 150 to 950 CE. To try to better understand the causes of the droughts across the Southwest, a 110-cm long ice core was drilled from an ice deposit in a lava tube (Cave 29) from El Malpais National Monument in west-central New Mexico. The δ18O values in the ice core (ranging from −11.78 to −3.54‰) …

Observational Constraints On The 520 Km Mantle Discontinuity, Mantle Transition Zone Anisotropy, And Local Seismicity At Mount St. Helens, Han Zhang

Earth and Planetary Sciences ETDs

Seismology provides valuable observational constraints to thermal and compositional states at inaccessible depths via understanding how elastic wave propagating through them. While many of fundament questions regarding solid Earth structures have been addressed during its more than 100 years history, some details remain unfilled and carefully designed approaches are needed to complete the pictures. This dissertation contributes observational constraints on three topics with newly developed methods. 1) We detected a controversial mantle discontinuity at about 520 km and concluded a mean mantle composition close to the Pyrolite model based on its seismic properties. 2) We isolated anisotropic effects in mantle …

Population Genetics Reveals Bidirectional Fish Movement Across The Continental Divide Via An Interbasin Water Transfer, Audrey C. Harris, Sara J. Oyler-Mccance, Jennifer A. Fike, Matthew P. Fairchild, Christopher M. Kennedy, Harry J. Crockett, Dana L. Winkelman, Yoichiro Kanno

United States Geological Survey: Staff Publications

Interbasin water transfers are becoming an increasingly common tool to satisfy municipal and agricultural water demand, but their impacts on movement and gene flow of aquatic organisms are poorly understood. The Grand Ditch is an interbasin water transfer that diverts water from tributaries of the upper Colorado River on the west side of the Continental Divide to the upper Cache la Poudre River on the east side of the Continental Divide. We used single nucleotide polymorphisms to characterize population genetic structure in cutthroat trout (Oncorhynchus clarkii) and determine if fish utilize the Grand Ditch as a movement corridor. …

A Technique-Based Approach To Structure-From-Motion: Applications To Human-Coastal Environments, Robert Van Alphen

USF Tampa Graduate Theses and Dissertations

Photogrammetry is a method by which physical information can be extracted from thecorrespondence of 2-dimensional images. In the geosciences, Structure-from-Motion (SfM) photogrammetry is a technique that has seen considerable interest in the past decade of research. Here I present three case studies of various scope and methodologies which can inform the use of SfM in the geosciences. First, I discuss the theoretical and algorithmic basis of SfM photogrammetry and its uses thus far in the geosciences. Chapters two through four show specific studies which highlight several approaches to SfM and the data which can be produced. Chapter five then concludes …

Differentiating Fissure-Fed Lava Flow Types And Facies Using Radar And Lidar: An Example From The 2014–2015 Holuhraun Lava Flow-Field, Gavin Douglas Tolometti, Catherine D. Neish, Christopher W. Hamilton, Gordon R. Osinski, Antero Kukko, Joana R.C. Voigt

Earth Sciences Publications

Distinguishing between lava types and facies using remote sensing data is important for interpreting the emplacement history of lava flow-fields on Earth and other planetary bodies. Lava facies typically include a mixture of lava types and record the collective emplacement history of material preserved at a particular location. We seek to determine if lava facies in the 2014–2015 Holuhraun lava flow-field are discernible using radar roughness analysis. Furthermore, we also seek to distinguish between lava types using high resolution Light Detection and Ranging (LiDAR) data. We extracted circular polarization ratios (CPR) from the Uninhabited Aerial Vehicle Synthetic Aperture Radar and …

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the role …

Foraging Habitat Selection Of Shrubland Bird Community In Tropical Dry Forest, Anant Deshwal, Steven L. Stephenson, Pooja Panwar, Brett A. Degregorio, Ragupathy Kannan, John D. Willson

United States Geological Survey: Staff Publications

Habitat loss due to increasing anthropogenic disturbance is the major driver for bird population declines across the globe. Within the Eastern Ghats of India, shrubland bird communities are threatened by shrinking of suitable habitats due to increased anthropogenic disturbance and climate change. The development of an effective habitat management strategy is hampered by the absence of data for this bird community. To address this knowledge gap, we examined foraging sites for 14 shrubland bird species, including three declining species, in three study areas representing the shrubland type of forest community in the Eastern Ghats. We recorded microhabitat features within an …

Determining Depth Of Closure Based On Time-Series Beach Profiles And Empirical Formulas: A Case Study Along The Florida Coast, Elizabeth Royer

USF Tampa Graduate Theses and Dissertations

Depth of closure (DOC) is defined as the most landward depth seaward of which there is no significant change in bed elevation and no significant net sediment exchange between the nearshore and the offshore over a certain period of time, such as 5 to 20 years. DOC is an essential parameter used in beach and shore protection, sediment management, and many other aspects of coastal studies. Taking advantage of advancements in wave hindcast and bathymetry measurement in the past 20 years (2000-2019), this study determined the DOC at 12 locations along the Florida coast, including three from the northwest Gulf …

Evaluating The Biogeochemical Effects Of Enhanced Rock Weathering At Lawrence University, Katie Mahorney

Lawrence University Honors Projects

On geologic timescales, the weathering of silicate rocks is among the most powerful negative feedbacks controlling atmospheric CO₂. However, this process is too slow to meaningfully impact our current climate crisis. Enhanced Rock Weathering (ERW) is one of the most promising carbon capture strategies to remove anthropogenic carbon from the atmosphere. Models suggest that by crushing silicate rocks such as basalt to increase surface area, the process of rock weathering can be accelerated to sequester enough carbon to be significant on human timescales. At Lawrence University, ERW is being investigated to (1) field test the efficacy of the …

Tree Ring Isotopic Reconstruction Of Hurricane Dolores, Jonathan Kane

Earth and Planetary Sciences ETDs

Tree rings contain high-resolution climate proxies of temperature and precipitation (Hughes et al., 1982; Fritts 2012; Scuderi 1993). The objective of this study was to use tree ring cellulose, specifically measuring δ18O - the oxygen-18 to oxygen-16 stable isotope ratio- to investigate the impact of Hurricane Dolores, a tropical cyclone that produced heavy precipitation in the Sierra Nevada in July 2015. Prior studies (Berkelhammer and Stott, 2008, 2009) have shown that conifer forests in California record the influence of varying precipitation regimes in their ring alpha-cellulose. Hurricane Dolores produced an intense precipitation event that inundated parts of the Mojave Desert …

Electron Backscatter Diffraction Analysis Of Olivine In Ureilite Meteorites: Evaluation Of The Partially Magmatic Catastrophic Disruption Model Of The Ureilite Parent Body (Upb), James Karl Frye

Dissertations and Theses

Past studies of olivine have yielded insights into crystallographic slip systems and how they are activated thermally. Using this information in conjunction with Electron Backscatter Diffraction (EBSD) analysis and metrics developed for chondrites, I constrained the thermal environment and the cooling rate for four ureilite meteorites in an attempt to test the model of catastrophic disruption of the ureilite parent body while it was partly molten. Present evidence for deformation, along with thermal metrics, were examined in order to conclude the following: Deformation of the meteorites took place at high temperatures followed by swift cooling, leaving little time for annealing. …

Geochronological And Geochemical Investigation Into Rhyolite Volcanism Of The High Lava Plains And Columbia River Basalt Group Provinces Of Eastern Oregon, Usa, Vanessa Marie Swenton

Dissertations and Theses

Voluminous and widespread bimodal volcanism has significantly impacted the Pacific Northwest, USA, throughout the Miocene to present day. The two primary volcanic provinces of eastern Oregon include the Columbia River Basalt Group (CRBG) province and the High Lava Plains (HLP) trend. The magmatic and tectonic processes responsible for generating bimodal volcanism, and particularly rhyolites of the ~17-15 Ma CRBG and 12-0 Ma HLP provinces has recently been a popular topic of debate. Rhyolite volcanism of the HLP province has been ascribed to either buoyancy-driven westward plume spreading or to slab rollback and mantle convection spanning from southeast Oregon to Newberry …

Preliminary Planning For Mars Sample Return (Msr) Curation Activities In A Sample Receiving Facility (Srf), Kimberly T. Tait, Francis M. Mccubbin, Caroline L. Smith, Carl B. Agee, Henner Busemann, Barbara Cavalazzi, Viciane Debaille, Aurore Hutzler, Tomohiro Usui, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Charles S. Cockell, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Bernard Marty, Lisa M. Pratt, Aaron B. Regberg, Alvin L. Smith, Roger E. Summons, Timothy D. Swindle, Nicholas J, Tosca, Arya Urdry, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The Mars Sample Return Planning Group 2 (MSPG2) was tasked with identifying the steps that encompass all the curation activities that would happen within the MSR Sample Receiving Facility (SRF) and any anticipated curation-related requirements. An area of specific interest is the necessary analytical instrumentation. The SRF would be a Biosafety Level-4 facility where the returned MSR flight hardware would be opened, the sample tubes accessed, and the martian sample material extracted from the tubes. Characterization of the essential attributes of each sample would be required to provide enough information to prepare a sample catalog used in guiding the preparation …

Science And Curation Considerations For The Design Of A Mars Sample Return (Msr) Sample Receiving Facility (Srf), Brandi L. Carrier, David W. Beaty, Aurore Hutzler, Alvin L. Smith, Gerhard Kminek, Michael A. Meyer, Timothy Haltigin, Lindsey E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cocksell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Bernard Marty, Francis M., Lisa M. Pratt, Aaron B. Regberg, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Taiit, Nocholas J. Tosca, Arya Urdry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The most important single element of the “ground system” portion of a Mars Sample Return (MSR) Campaign is a facility referred to as the Sample Receiving Facility (SRF), which would need to be designed and equipped to receive the returned spacecraft, extract and open the sealed sample container, extract the samples from the sample tubes, and implement a set of evaluations and analyses of the samples. One of the main findings of the first MSR Sample Planning Group (MSPG, 2019a) states that “The scientific community, for reasons of scientific quality, cost, and timeliness, strongly prefers that as many sample-related investigations …

The Scientific Importance Of Returning Airfall Dust As A Part Of Mars Sample Return (Msr), Monica M. Grady, Roger E. Summons, Timothy D. Swindle, Frances Westall, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Galvin, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B, Regberg, Alvin L. Smith, Caroline L. Smith, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Maria-Paz Zorzano

Geoscience Faculty Research

Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache depots on the martian surface perhaps as early as 2023–24 for recovery by a subsequent mission no earlier than 2028–29, and possibly as late as 2030–31. Thus, the sample tube surfaces could passively collect dust for multiple years. This dust is deemed to be exceptionally valuable as it …

Time-Sensitive Aspects Of Mars Sample Return (Msr) Science, Nicholas J. Tosca, Carl B. Agee, Charles S. Cockell, Daniel P. Glavin, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Aaron B. Regberg, Michael A. Velbel, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Henner Baumann, Barbara Cavalazzi, Vinviane Debaille, Monica M. Grady, Ernst Hauber, Lisa M. Pratt, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

Samples returned from Mars would be placed under quarantine at a Sample Receiving Facility (SRF) until they are considered safe to release to other laboratories for further study. The process of determining whether samples are safe for release, which may involve detailed analysis and/or sterilization, is expected to take several months. However, the process of breaking the sample tube seal and extracting the headspace gas will perturb local equilibrium conditions between gas and rock and set in motion irreversible processes that proceed as a function of time. Unless these time-sensitive processes are understood, planned for, and/or monitored during the quarantine …

Planning Implications Related To Sterilization-Sensitive Science Investigations Associated With Mars Sample Return (Msr), Michael A. Velbel, Charles S. Cockell, Daniel P. Glavin, Bernard Marty, Aaron B. Regberg, Alvin L. Smith, Nicholas J. Tosca, Meenakshi Wadhwa, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi Lee Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barbara Cavalazzi, Vinciane Debaille, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Francis M. Mccubbin, Lisa M. Pratt, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The NASA/ESA Mars Sample Return (MSR) Campaign seeks to establish whether life on Mars existed where and when environmental conditions allowed. Laboratory measurements on the returned samples are useful if what is measured is evidence of phenomena on Mars rather than of the effects of sterilization conditions. This report establishes that there are categories of measurements that can be fruitful despite sample sterilization and other categories that cannot. Sterilization kills living microorganisms and inactivates complex biological structures by breaking chemical bonds. Sterilization has similar effects on chemical bonds in non-biological compounds, including abiotic or pre-biotic reduced carbon compounds, hydrous minerals, …

Final Report Of The Mars Sample Return Science Planning Group 2 (Mspg2), Michael A. Meyer, Gerhard Kminek, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agree, Henner Busemann, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B. Regberg, Alvin L. Smith, Carolina L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meensakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The Mars Sample Return (MSR) Campaign must meet a series of scientific and technical achievements to be successful. While the respective engineering responsibilities to retrieve the samples have been formalized through a Memorandum of Understanding between ESA and NASA, the roles and responsibilities of the scientific elements have yet to be fully defined. In April 2020, ESA and NASA jointly chartered the MSR Science Planning Group 2 (MSPG2) to build upon previous planning efforts in defining 1) an end-to-end MSR Science Program and 2) needed functionalities and design requirements for an MSR Sample Receiving Facility (SRF). The challenges for the …

Rationale And Proposed Design For A Mars Sample Return (Msr) Science Program, Timothy Haltigin, Ernst Hauber, Gerhard Kminek, Michael A. Meyer, Carl B. Agee, Henner Busemann, Brandi L. Carrier, Daniel P. Glavin, Lindsay E. Hays, Bernard Marty, Lisa M. Pratt, Arya Udry, Maria-Paz Zorzano, David W. Beaty, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Monica M. Grady, Aurore Hutzler, Francis M. Mccubbin, Aaron B. Regberg, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall

Geoscience Faculty Research

The Mars Sample Return (MSR) Campaign represents one of the most ambitious scientific endeavors ever undertaken. Analyses of the martian samples would offer unique science benefits that cannot be attained through orbital or landed missions that rely only on remote sensing and in situ measurements, respectively. As currently designed, the MSR Campaign comprises a number of scientific, technical, and programmatic bodies and relationships, captured in a series of existing and anticipated documents. Ensuring that all required scientific activities are properly designed, managed, and executed would require significant planning and coordination. Because there are multiple scientific elements that would need to …

Fossils On The Floor Mosaics In The Rotunda Of The Nebraska State Capitol Second Edition, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The idea for this project arose during a field trip to the Nebraska State Capitol led by my long-time friend and colleague, Joe Hannibal, of the Cleveland Museum of Natural History, during the Geological Society of America’s North-Central Section Meeting in Lincoln, Nebraska, on Saturday, April 26, 2014. One of Joe’s interests is historical buildings and their building stones. He put together a very useful guidebook to the building and its decorative stones (Hannibal, 2014) that we used on our tour.

One of the many places that we visited was the State Capitol Archives, located in the basement, where the …

Water And Soil Gas Sampling Near Richardton, North Dakota, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet on a 2019 Energy & Environmental Research Center project to collect water and soil gas samples near Richardton, North Dakota, as part of the Red Trail Energy carbon capture and storage (CCS) research effort. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Analysis Of Aftershock Parameters For The Alaskan Subduction Zone Tectonic Region, Gabrielle M. Paris

Geology Undergraduate Honors Theses

Forecasting how many earthquakes will occur following a potentially damaging earthquake helps the public and emergency operators stay safe and make informed decisions. The U.S. Geological Survey issues aftershock forecasts following potentially damaging earthquakes, using models to predict the number of earthquakes that should occur within the next day, week, month, and year with 95% confidence to reflect the uncertainty in aftershock behavior. The USGS considers the forecast to be "successful" when the number of earthquakes observed within the forecasted time period is within the 95% confidence interval. For aftershock sequences that occur along the forearc of the Alaskan subduction …

Fluid Pathways In Magmatic Fluid-Dominated Hydrothermal System: Upper Resurgent Cone, Brothers Volcano, New Zealand, Esther G. Goita

Honors Theses

The Tonga-Kermadec Arc is an active volcanic arc located between New Zealand and Fiji. The arc expands over an approximate distance of 2530 km. The Kermadec Arc is currently host to over 30 volcanoes, the majority of which are submarine. The magmatic activity along the arc is characterized by the convergence between the Pacific and Australian plates. Brothers volcano is the most active hydrothermal system along the Kermadec arc and hosts two distinct hydrothermal systems, one magmatic fluid dominated, and the other seawater dominated, making the site perfect for studying nascent volcanogenic massive sulfide formation and fluid pathways. The International …

Speciation With Gene Flow In A Narrow Endemic West Virginia Cave Salamander (Gyrinophilus Subterraneus), Evan H. Campbell Grant, Kevin P. Mulder, Adrianne B. Brand, Douglas B. Chambers, Addison H. Wynn, Grace Capshaw, Matthew L. Niemiller, John G. Phillips, Jeremy F. Jacobs, Shawn R. Kuchta, Rayna C. Bell

United States Geological Survey: Staff Publications

Due to their limited geographic distributions and specialized ecologies, cave species are often highly endemic and can be especially vulnerable to habitat degradation within and surrounding the cave systems they inhabit. We investigated the evolutionary history of the West Virginia Spring Salamander (Gyrinophilus subterraneus), estimated the population trend from historic and current survey data, and assessed the current potential for water quality threats to the cave habitat. Our genomic data (mtDNA sequence and ddRADseq-derived SNPs) reveal two, distinct evolutionary lineages within General Davis Cave corresponding to G. subterraneus and its widely distributed sister species, Gyrinophilus porphyriticus, that …