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Full-Text Articles in Physical Sciences and Mathematics

A Secure Computing Platform For Building Automation Using Microkernel-Based Operating Systems, Xiaolong Wang Nov 2018

A Secure Computing Platform For Building Automation Using Microkernel-Based Operating Systems, Xiaolong Wang

USF Tampa Graduate Theses and Dissertations

Building Automation System (BAS) is a complex distributed control system that is widely deployed in commercial, residential, industrial buildings for monitoring and controlling mechanical/electrical equipment. Through increasing industrial and technological advances, the control components of BAS are becoming increasingly interconnected. Along with potential benefits, integration also introduces new attack vectors, which tremendous increases safety and security risks in the control system. Historically, BAS lacks security design and relies on physical isolation and "security through obscurity". These methods are unacceptable with the "smart building" technologies. The industry needs to reevaluate the safety and security of the current building automation system, and …


On The Feasibility Of Profiling, Forecasting And Authenticating Internet Usage Based On Privacy Preserving Netflow Logs, Soheil Sarmadi Nov 2018

On The Feasibility Of Profiling, Forecasting And Authenticating Internet Usage Based On Privacy Preserving Netflow Logs, Soheil Sarmadi

USF Tampa Graduate Theses and Dissertations

Understanding Internet user behavior and Internet usage patterns is fundamental in developing future access networks and services that meet technical as well as Internet user needs. User behavior is routinely studied and measured, but with different methods depending on the research discipline of the investigator, and these disciplines rarely cross. We tackle this challenge by developing frameworks that the Internet usage statistics used as the main features in understanding Internet user behaviors, with the purpose of finding a complete picture of the user behavior and working towards a unified analysis methodology. In this dissertation we collected Internet usage statistics via …


An Analytical Solution For Attainment Of Field Capacity, Ali Aldrees Nov 2018

An Analytical Solution For Attainment Of Field Capacity, Ali Aldrees

USF Tampa Graduate Theses and Dissertations

Field Capacity (FC) is a key parameter to quantify in agricultural engineering, irrigation controlling, and soil physics studies. For instance, irrigation studies focuses on determining the optimal amount of water needed by plants to grow following an irrigation system and therefore relies on determining FC. Likewise, the value of FC is a good indicator of soil textures, structures and pore size distributions. For example, loamy soils have a wider distribution of pores leading to high FC values. FC depends on multiple physically-grounded variables which include matric potential value (ψ_FC ), water content at FC (θ_FC ), specific drainage time to …


Lump Solutions And Riemann-Hilbert Approach To Soliton Equations, Sumayah A. Batwa Nov 2018

Lump Solutions And Riemann-Hilbert Approach To Soliton Equations, Sumayah A. Batwa

USF Tampa Graduate Theses and Dissertations

In the first part of this dissertation we introduce two matrix iso-spectral problems, a Kaup-Newell type and a generalization of the Dirac spectral problem, associated with the three-dimensional real Lie algebras sl(2;R) and so(3;R), respectively. Through zero curvature equations, we furnish two soliton hierarchies. Hamiltonian structures for the resulting hierarchies are formulated by adopting

the trace identity. In addition, we prove that each of the soliton hierarchies has a bi-Hamiltonian structure which leads to the integrability in the Liouville sense. The motivation of the first part is to construct soliton hierarchies with infinitely many commuting symmetries and conservation laws.

The …


Evaluating The Use Of Larval Connectivity Information In Fisheries Models And Management In The Gulf Of Mexico, Michael Drexler Nov 2018

Evaluating The Use Of Larval Connectivity Information In Fisheries Models And Management In The Gulf Of Mexico, Michael Drexler

USF Tampa Graduate Theses and Dissertations

Connectivity is a major contributor to the overall dynamics of marine populations. However, it still remains challenging to describe connectivity on ecologically meaningful scales of time and space. This is a major impediment to evaluating the impacts of marine protected area with respect to fisheries management objectives.

This dissertation brings together a wide array of spatial and connectivity information in the Gulf of Mexico (GOM) with the goal of 1) understanding the spatial distribution of fish populations and source-sink dynamics and 2) evaluating whether this information can be integrated, through a modeling framework, to identify closed areas that could be …


Quantifying The Probability Of Lethal Injury To Florida Manatees Given Characteristics Of Collision Events., B. Lynn Combs Nov 2018

Quantifying The Probability Of Lethal Injury To Florida Manatees Given Characteristics Of Collision Events., B. Lynn Combs

USF Tampa Graduate Theses and Dissertations

Wherever wildlife share space with boaters, collisions are a potential source of mortality. Establishing protection and speed zones are the primary actions taken to mitigate collision risk. However, creation of protection zones may be a point of contention with stakeholders as new zones can have significant socioeconomic impacts. The Florida Manatee is a prime example of a species whose abundance and viability are constrained by this balance between the needs of humans and wildlife on a shared landscape. The goal of this work is to help further understand the risk to manatees by quantifying the probability of lethal collisions. I …


A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic Nov 2018

A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic

USF Tampa Graduate Theses and Dissertations

This thesis aims to provide a general overview of a cost and benefit analysis of incorporating a battery energy storage system within unit commitment model.

The deregulation of the electricity market in the U.S. has only been around for the last two decades. With renewable energy and energy storage systems becoming less expensive, a decentralized market scheme is becoming more popular and plausible. The scope of this work is to provide a fundamental understanding of unit commitment and a cost analysis of applying a battery energy storage system to an already established power system.

A battery energy storage system (BESS) …


Analysis And New Applications Of Metal Organic Frameworks (Mof): Thermal Conductivity Of A Perovskite-Type Mof And Incorporation Of A Lewis Pair Into A Mof., Wilarachchige D C B Gunatilleke Nov 2018

Analysis And New Applications Of Metal Organic Frameworks (Mof): Thermal Conductivity Of A Perovskite-Type Mof And Incorporation Of A Lewis Pair Into A Mof., Wilarachchige D C B Gunatilleke

USF Tampa Graduate Theses and Dissertations

Metal organic frameworks have gained much attention due to their tunable pore sizes and very high surface areas. With the discovery many of these type materials the need has raised to look into new applications of theses porous frameworks. This thesis focuses on the synthesis of a new perovskite-type metal organic framework and measurement of its thermal conductivity in search of its applicability as a thermoelectric material. The second part of this work focuses on the synthesis of a metal organic framework incorporated with a Lewis pair for the first time. The optimum loading amount of the Lewis pair into …


Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich Nov 2018

Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich

USF Tampa Graduate Theses and Dissertations

Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the …


Comparison Of Modeled And Measured Pesticide Concentrations In Air, Trenell Davis Boggans Nov 2018

Comparison Of Modeled And Measured Pesticide Concentrations In Air, Trenell Davis Boggans

USF Tampa Graduate Theses and Dissertations

Chlorpyrifos (CPF) is a popular organophosphorus insecticide that is heavily used in the agriculture industry as a means of pest control. Chlorpyrifos is known for its toxic effect to inhibit the enzyme acetylcholinesterase (ACHE) in humans and is widely used in areas of California where the site of application is close to occupied areas, such that exposures to residents and bystanders can occur due to secondary drift. Secondary drift refers to the volatilization of a pesticide from the surface to which it was applied (e.g. soil or plant foliage) and subsequent off-site movement in ambient air. Secondary drift is different …


Optimizing Peptide Fractionation To Maximize Content In Cancer Proteomics, Victoria Izumi Nov 2018

Optimizing Peptide Fractionation To Maximize Content In Cancer Proteomics, Victoria Izumi

USF Tampa Graduate Theses and Dissertations

The purpose of the studies included in this thesis is to develop an effective an efficient method to study the proteome using separation and detection of peptides, when only a limited amount of sample, 10 micrograms of total protein or less, is available. The analysis will be applied to multiple myeloma cancer cells using ultra high-performance liquid chromatography-mass spectrometry for expression proteomics to illustrate utility. To detect low abundance peptides in a complex proteome, we use different strategies, including basic pH reversed-phase liquid chromatography (bRPLC), mass-to-charge fractionation in the mass spectrometer, and various liquid chromatography gradients to increase peptide separation …


Validation Of The Thermal Work Limit (Twl) Against Known Heat Stress Exposures, Danielle L. Kapanowski Nov 2018

Validation Of The Thermal Work Limit (Twl) Against Known Heat Stress Exposures, Danielle L. Kapanowski

USF Tampa Graduate Theses and Dissertations

Workers are exposed to stressful thermal work environments in multiple industries every day. Methods for assessing heat stress often struggle to balance productivity without compromising the health of the workers. The Thermal Work Limit (TWL) is a method that has been adopted in areas outside of the United States as a viable method for heat assessment that combines health with productivity. TWL recommends a maximum metabolic rate for a given set of environmental conditions, clothing ensemble and acclimatization state. The purpose of this paper was to evaluate the validity of the TWL against a set of heat stress data known …


Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen Oct 2018

Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen

USF Tampa Graduate Theses and Dissertations

Surface ocean partial pressure of CO2 (pCO2) is a critical parameter in the quantification of air-sea CO2 flux, which further plays an important role in quantifying the global carbon budget and understanding ocean acidification. The demand for a clearer understanding of how, and how fast, the ocean is changing due to atmospheric CO2 absorption, requires accurate and synoptic estimation of surface pCO2.

Surface ocean pCO2 is mainly controlled by four oceanic processes – thermodynamics, ocean mixing, biological activities, and air-sea CO2 exchange. Surface ocean pCO2 …


Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter Oct 2018

Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter

USF Tampa Graduate Theses and Dissertations

Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …


Do Slow Slip Events Trigger Large And Great Megathrust Earthquakes?, N. Voss, Timothy H. Dixon, Z. Liu, Rocco Malservisi, M. Protti, S. Schwartz Oct 2018

Do Slow Slip Events Trigger Large And Great Megathrust Earthquakes?, N. Voss, Timothy H. Dixon, Z. Liu, Rocco Malservisi, M. Protti, S. Schwartz

School of Geosciences Faculty and Staff Publications

Slow slip events have been suggested to trigger subduction earthquakes. However, examples to date have been poorly recorded, occurring offshore, where data are sparse. Better understanding of slow slip events and their influence on subsequent earthquakes is critical for hazard forecasts. We analyze a well-recorded event beginning 6 months before the 2012 Mw (moment magnitude) 7.6 earthquake in Costa Rica. The event migrates to the eventual megathrust rupture. Peak slip rate reached a maximum of 5 mm/day, 43 days before the earthquake, remaining high until the earthquake. However, changes in Mohr-Coulomb failure stress at the hypocenter were small (0.1 …


An Investigation Of Habitat Suitability Factors And Their Interactions For Predicting Gopher Tortoise Habitat, Abigail V. Lavallin Oct 2018

An Investigation Of Habitat Suitability Factors And Their Interactions For Predicting Gopher Tortoise Habitat, Abigail V. Lavallin

USF Tampa Graduate Theses and Dissertations

This thesis evaluates the interaction between four habitat factors vital to the gopher tortoise in Florida. Federally and state listed as threatened throughout its entire range, the gopher tortoise is vital to protect, not only for itself individually but its burrows provide an essential habitat to over 300 species making it a key stone species within its environment. Historic habitat modeling methods are reviewed for the gopher tortoise to highlight the gap on this topic. This research expanded on the methods utilized by Baskaran et al. (2006) evaluating the soil, landcover, percentage of canopy cover and the depth to water …


Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall Oct 2018

Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall

USF Tampa Graduate Theses and Dissertations

Shell Key and Mullet Key are two sandy barrier islands on the West Central Florida coast near the mouth of Tampa Bay. These islands are part of an interconnected barrier-inlet system that includes Pass-a-Grille (PAG) and Bunces Pass. Shell Key is a relatively new island about 40-years of age that formed in between the two inlets of Bunces Pass and PAG. Mullet Key is an island to the south of Shell Key situated between Bunces Pass and the main Tampa Bay channel that has demonstrated large scale upward shoaling events. Using numerical modeling, the wave and tidal conditions at the …


Access To Safe Water Supply: Management Of Catchment For The Protection Of Source Water In Ghana, Michael K. Eduful Oct 2018

Access To Safe Water Supply: Management Of Catchment For The Protection Of Source Water In Ghana, Michael K. Eduful

USF Tampa Graduate Theses and Dissertations

This study investigates provisions made within institutional and regulatory frameworks of water resources management to enhance multi-stakeholder relationships and the challenges of maintaining those relationships, and implications of water resources management for rural communities in the Densu River basin, Ghana. The primary objectives of this study were four fold, these are to: i) review the existing regulatory framework and how it promotes or hinders multi-stakeholder relationships within the catchment area; ii) examine multi-stakeholder relationships to identify challenges in promoting effective collaboration in water resources management; iii) explore the impacts of catchment management on the livelihoods of rural communities; and iv) …


Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa Oct 2018

Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa

USF Tampa Graduate Theses and Dissertations

Water resources in Florida have been severely degraded by eutrophic conditions, resulting toxic algae blooms, which negatively affect health and tourism. Eutrophication, or excessive amount of phosphorus (P) and nitrogen (N) in water, overstimulates the production of aquatic plants, depletes dissolved oxygen, and deteriorates the aquatic environment. However, phosphorus is a non-renewable resource essential for all living organisms. In fact, more than half of the total demand for P globally is to supply the food industry, which has concerningly accelerated the depletion rates of phosphate reserves.

In many wastewater treatment plants (WWTPs), the enhanced biological phosphorus removal (EBPR) approach has …


Emotion Recognition Using Deep Convolutional Neural Network With Large Scale Physiological Data, Astha Sharma Oct 2018

Emotion Recognition Using Deep Convolutional Neural Network With Large Scale Physiological Data, Astha Sharma

USF Tampa Graduate Theses and Dissertations

Classification of emotions plays a very important role in affective computing and has real-world applications in fields as diverse as entertainment, medical, defense, retail, and education. These applications include video games, virtual reality, pain recognition, lie detection, classification of Autistic Spectrum Disorder (ASD), analysis of stress levels, and determining attention levels. This vast range of applications motivated us to study automatic emotion recognition which can be done by using facial expression, speech, and physiological data.

A person’s physiological signals such are heart rate, and blood pressure are deeply linked with their emotional states and can be used to identify a …


Merging The Concepts Of Pseudokarst And Paleoseismicity In Sweden: A Unified Theory On The Formation Of Fractures, Fracture Caves, And Angular Block Heaps, Nils-Axel Mörner, Rabbe Sjöberg Oct 2018

Merging The Concepts Of Pseudokarst And Paleoseismicity In Sweden: A Unified Theory On The Formation Of Fractures, Fracture Caves, And Angular Block Heaps, Nils-Axel Mörner, Rabbe Sjöberg

International Journal of Speleology

Sweden has thousands of caves cut into the bedrock, two thirds of which occur in the crystalline bedrock, and hence represent pseudokarst phenomena. The formation of these caves can only be understood in terms of paleoseismics. In this paper, we review the parallel evolution of the concept of pseudokarst caves and of the concept of paleoseismic activity in Sweden, and combine both concepts into a unified theory on the formation of fractures, fracture caves and angular block heaps.


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

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

International Journal of Speleology

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


Drone Movement Control Using Gesture Recognition From Wearable Devices, Venkata Sireesha Dadi Oct 2018

Drone Movement Control Using Gesture Recognition From Wearable Devices, Venkata Sireesha Dadi

USF Tampa Graduate Theses and Dissertations

Gesture Recognition is a new and upcoming trend that is being widely used in wearable devices and mobile handheld devices. The sensors like Accelerometer, Gyroscope, Heart rate monitor, Barometer and Ambient Light are mostly being included within the device to detect the static or continuous motion, rotational velocity, heartbeat rate of the user, pressure and light conditions for the device respectively. Implementing algorithms to capture the readings of these sensors and implementing them in a necessary way allows a user to use the wearable devices for a wide variety of applications. One such application is controlling Drone that takes user …


Groups Generated By Automata Arising From Transformations Of The Boundaries Of Rooted Trees, Elsayed Ahmed Oct 2018

Groups Generated By Automata Arising From Transformations Of The Boundaries Of Rooted Trees, Elsayed Ahmed

USF Tampa Graduate Theses and Dissertations

In this dissertation we study groups of automorphisms of rooted trees arising from the transformations of the boundaries of these trees. The boundary of every regular rooted tree can be endowed with various algebraic structures. The transformations of these algebraic structures under certain conditions induce endomorphisms or automorphisms of the tree itself that can be described using the language of Mealy automata. This connection can be used to study boundarytransformations using the propertiesof the induced endomorphisms, or vice versa.

We concentrate on two ways to interpret the boundary of the rooted d-regular tree. In the first approach discussed in detail …


Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter Oct 2018

Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter

USF Tampa Graduate Theses and Dissertations

Analyses of foraminiferal assemblages involve time consuming microscopic assessment of sediment samples. Image recognition software, which systematically matches features within sample images against an image library, is widely used in contexts ranging from law enforcement to medical research. At present, scientific applications such as identification of specimens in plankton samples utilize flow through systems in which samples are suspended in liquid and pass through a beam of light where the images are captured using transmitted light. Identification of foraminifers generally utilizes reflected light, because most shells are relatively opaque.

My goal was to design and test a protocol to directly …


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

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

International Journal of Speleology

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


Correlates Of Rate Heterogeneity In Avian Ecomorphological Traits, A. M. Chira, C. R. Cooney, Jen A. Bright, E. J. R. Capp, E. C. Hughes, C. J. A. Moody, L. O. Nouri, Z. K. Varley, G. H. Thomas Oct 2018

Correlates Of Rate Heterogeneity In Avian Ecomorphological Traits, A. M. Chira, C. R. Cooney, Jen A. Bright, E. J. R. Capp, E. C. Hughes, C. J. A. Moody, L. O. Nouri, Z. K. Varley, G. H. Thomas

School of Geosciences Faculty and Staff Publications

Heterogeneity in rates of trait evolution is widespread, but it remains unclear which processes drive fast and slow character divergence across global radiations. Here, we test multiple hypotheses for explaining rate variation in an ecomorphological trait (beak shape) across a globally distributed group (birds). We find low support that variation in evolutionary rates of species is correlated with life history, environmental mutagenic factors, range size, number of competitors, or living on islands. Indeed, after controlling for the negative effect of species' age, 80% of variation in species‐specific evolutionary rates remains unexplained. At the clade level, high evolutionary rates are associated …


Development Of Bioactive Peptidomimetics, Fengyu She Oct 2018

Development Of Bioactive Peptidomimetics, Fengyu She

USF Tampa Graduate Theses and Dissertations

Peptidomimetics are synthetic foldamers that expected more resistant to proteolytic degradation and enormous chemodiversity when compared with peptides. To date, the functional peptidomimetics such as β-peptides, peptoids, oligoureas, etc have been developed in many science fields. In order to explore the unnatural foldameric architectures, it’s necessary to discover the novel frameworks and molecular scaffolds. γ-AApeptides were reported to be a new class of peptidomimetics that showed its potential applications in drug discovery and chemical biology. However, a wide function and property of γ-AApeptides need to be further explored. To expand the potential application of γ-AApeptides in biochemistry, I have been …


A Fundamental Investigation Into Low Thermal Conductivity P-Type Chalcogenides And Skutterudites With Potential Thermoelectric Applications, Dean Hobbis Sep 2018

A Fundamental Investigation Into Low Thermal Conductivity P-Type Chalcogenides And Skutterudites With Potential Thermoelectric Applications, Dean Hobbis

USF Tampa Graduate Theses and Dissertations

Sustainable and renewable energy is an incredibly important area in today’s society and investigation into avenues to improve this wide ranging technology are underway in many different fields. Thermoelectric devices possess the ability for the direct solid-state interconversion of heat and electrical power, which not only allows for sustainable refrigeration but also waste heat recovery. One current restriction on the efficiency of thermoelectric devices is the disparity in thermoelectric performance of p-type and n-type materials. Furthermore, a key physical attribute shared by the majority of high performing thermoelectric materials is low thermal conductivity. Thus in this thesis three separate p-type …


Sulfur (34S/32S) Isotope Composition Of Gypsum And Implications For Deep Cave Formation On The Nullarbor Plain, Australia, Matej Lipar, Mateja Ferk, Sonja Lojen, Milo Barham Sep 2018

Sulfur (34S/32S) Isotope Composition Of Gypsum And Implications For Deep Cave Formation On The Nullarbor Plain, Australia, Matej Lipar, Mateja Ferk, Sonja Lojen, Milo Barham

International Journal of Speleology

Large deep caves with little relation to surface topography are distinctive karst features on the Nullarbor Plain of Australia. The presence of gypsum deposits and chemoautotrophic bacteria within the caves have been suggested as evidence for cave formation and (or) enlargement via sulfuric acid speleogenesis. To test this hypothesis, the stable sulfur isotope compositions (δ34S) of both cave gypsum and surface gypsum were measured. Analyses yielded relatively high, positive δ34S values from both cave gypsum and surface gypsum, arguing against gypsum genesis via microbial chemoautotrophy, and more broadly, sulfuric acid speleogenesis. Instead, the gypsum is interpreted …