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Full-Text Articles in Physical Sciences and Mathematics

Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág Feb 2024

Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág

International Journal of Speleology

Clumped isotope measurements of carbonates and stable isotope analyses of water trapped in fluid inclusions are both promising techniques to determine carbonate formation temperatures. Cave-hosted carbonate deposits (speleothems) are excellent targets for such studies, but kinetic fractionations and diagenetic influences frequently deteriorate the temperature data obtained from these methods. However, subaqueous carbonate deposits may provide reliable data, as kinetic fractionations are less significant in underwater environments. In this study, subaqueous speleothems, whose formation temperatures were directly measured in the water, were investigated. Additionally, temperatures calculated from the oxygen isotope fractionations between calcite and fluid inclusion-hosted water were compared with clumped …


Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti Dec 2023

Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti

International Journal of Speleology

A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of …


Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford Oct 2023

Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford

USF Tampa Graduate Theses and Dissertations

Nickel (Ni) is an important micronutrient for phytoplankton and bacteria that serves as a required co-factor in several metalloenzymes. Despite these known biological uses, total dissolved Ni concentrations remain elevated in global surface waters, in contrast to the surface depletion commonly observed for macronutrients and other nutrient-type trace elements. A prevailing hypothesis for the muted depletion of dissolved Ni concentrations in surface waters is that dissolved Ni in seawater is not in a bioavailable form. The chemical lability of Ni in seawater provides insight into Ni speciation and bioavailability, but few measurements have been made in the open ocean to …


Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford Oct 2023

Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford

USF Tampa Graduate Theses and Dissertations

Nickel (Ni) is an important micronutrient for phytoplankton and bacteria that serves as a required co-factor in several metalloenzymes. Despite these known biological uses, total dissolved Ni concentrations remain elevated in global surface waters, in contrast to the surface depletion commonly observed for macronutrients and other nutrient-type trace elements. A prevailing hypothesis for the muted depletion of dissolved Ni concentrations in surface waters is that dissolved Ni in seawater is not in a bioavailable form. The chemical lability of Ni in seawater provides insight into Ni speciation and bioavailability, but few measurements have been made in the open ocean to …


Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett Jun 2023

Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett

USF Tampa Graduate Theses and Dissertations

A method for gas chromatography tandem mass spectrometry (GC-MS/MS) in selected reaction monitoring (SRM) mode has been optimized to quantify 250 compounds of a variety of compound classes such as polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, organochlorinated pesticides, polychlorinated biphenyls, biomarkers (hopanes, steranes, tri-aromatic steroids, and fecal sterols), aliphatic hydrocarbons, and plastic additives. This method was validated based on available QA/QC standards using several environmental samples, both sediment and biota, and standard reference materials. This contaminant-focused method can be used as a forensic geochemistry tool to evaluate oil contamination and other contaminant histories in future research studies. When applied to …


Lithium And Lithium Isotope Behavior During High Temperature Solid/Fluid Exchanges: Examples From Iceland And The Izu-Bonin Forearc, Alex Maruszczak Mar 2023

Lithium And Lithium Isotope Behavior During High Temperature Solid/Fluid Exchanges: Examples From Iceland And The Izu-Bonin Forearc, Alex Maruszczak

USF Tampa Graduate Theses and Dissertations

The development of a method for lithium isotopic measurement was developed using a quadrupole, single-collector ICP-MS. Measured precision was ±1.00‰ 2σ over a 15-month period based on measurements of international rock standards. A 1-hour leach using cold, HCl was sufficient to remove alteration-related Li in minimally to moderately altered seafloor basalts. Measurements on the Holocene ages lavas from the neovolcanic zones of Iceland suggest no systematic Li isotopic variability among the differing Icelandic sources. Felsic samples from Hekla and Pumice contain elevated Li contents of >18ug/g while the tholeiitic and alkaline basalts are <8ug/g Li. Most of the island lies around MORB values of ~+3 to +5‰ with the exception of Western Volcanic Zone samples that show evidence for seawater inputs. The RN-17 drillcore, which penetrates >3000m through a hydrothermal system in the …


Cryogenic Ridges: A New Speleothem Type, Bogdan P. Onac, Daniel M. Cleary, Oana A. Dumitru, Victor J. Polyak, Ioan Povara, Jonathan G. Wynn, Yemane Asmerom Jan 2023

Cryogenic Ridges: A New Speleothem Type, Bogdan P. Onac, Daniel M. Cleary, Oana A. Dumitru, Victor J. Polyak, Ioan Povara, Jonathan G. Wynn, Yemane Asmerom

International Journal of Speleology

Cryogenic cave carbonates have been described from several formerly or presently glaciated karst caves. In most of these occurrences, they precipitated as loose grains or aggregates with various morphologies and sizes. Here, we report on a new speleothem type (cryogenic ridges) identified in Sohodoalele Mici Cave (SW Romania) within a large chamber near the entrance shaft. This study was motivated by the presence of a network of calcite ridges over the stalactites’ surface and by the observation that during winter, these speleothems are covered by a thin ice layer. The higher δ18O (−3.5 to –1‰) and …


Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud Apr 2022

Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Isoscapes are depictions of the spatial patterns of isotopic values in a given area. Isoscapes can be created using measurements form samples (empirical isoscapes) or using statistical models of spatial isotopic variation (modeled isoscapes). Isoscapes have a wide variety of potential applications though, in the realm of marine ecology, they are most often used infer ecological processes, food web linkages, the origin of samples, and the movements of marine organisms.

However, to use isoscapes for these applications, it is necessary to have isoscapes at spatial scales relevant to the application in question. It is also necessary to have isoscapes that …


Low Impact Sampling Of Speleothems – Reconciling Scientific Study With Cave Conservation, Claire L.V. Macgregor, John C. Hellstrom, Jon D. Woodhead, Russell N. Drysdale, Rolan S. Eberhard Nov 2021

Low Impact Sampling Of Speleothems – Reconciling Scientific Study With Cave Conservation, Claire L.V. Macgregor, John C. Hellstrom, Jon D. Woodhead, Russell N. Drysdale, Rolan S. Eberhard

International Journal of Speleology

Speleothems are increasingly valued as important paleoclimate archives and yet the removal of samples from caves can come at a cost to natural heritage, impacting delicate environments with limited mechanisms for repair. Conservation of cave environments is a key responsibility for scientists and, with this in mind, we are working to develop and implement techniques that allow us to extract valuable scientific data, with minimal impact. In this study, we demonstrate the utility of low-impact reconnaissance dating surveys on caves in southern Tasmania and southwest Western Australia as a precursor to the removal of stalagmites for paleoclimate reconstruction. Small flakes …


Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll Oct 2021

Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll

International Journal of Speleology

Because they can archive a variety of geochemical proxies and be precisely and accurately dated with the U-Th decay series chronometer, stalagmites are widely used for paleoclimate reconstructions. However, limitations in the use of this chronometer arise because U-Th dating is analytically time consuming, expensive, and requires a relatively large sample size. These limitations restrict the number of absolute dates usually obtained, which can result in significant uncertainties in the age model and inhibit the ability to archive high resolution records of environmental variability, particularly in those stalagmites where there are variations in growth rate not constrained by U-Th dates. …


Geochemistry Of Phosphatic Nodules As A Tool For Understanding Depositional And Taphonomical Settings In A Palaeolithic Cave Site (San Teodoro, Sicily), Gerlando Vita, Vittorio Garilli, Mirko Andrea Vizzini, Renato Giarrusso, Angelo Mulone, Massimiliana Pinto Vraca, Valeria La Parola, Pierluigi Rosina, Laura Bonfiglio, Luca Sineo Sep 2021

Geochemistry Of Phosphatic Nodules As A Tool For Understanding Depositional And Taphonomical Settings In A Palaeolithic Cave Site (San Teodoro, Sicily), Gerlando Vita, Vittorio Garilli, Mirko Andrea Vizzini, Renato Giarrusso, Angelo Mulone, Massimiliana Pinto Vraca, Valeria La Parola, Pierluigi Rosina, Laura Bonfiglio, Luca Sineo

International Journal of Speleology

Interpreting depositional settings of cave sites is generally problematic, especially in absence of paleontological/archaeological evidence. This is the case of some deposits at San Teodoro Cave (Sicily), a key site for the Mediterranean Palaeolithic. In a stratigraphic level interrupted by a carbonatic concretion, phosphatic nodules are present only in the part enclosed between the concretion and the cave wall. The discovery of these nodules combined with the punctual lack of fossils had initially suggested an erosion phenomenon and subsequent formation of nodules at a vadose level. Here we show the usefulness of an integrated, geochemical-paleoecological approach in defining stratigraphy and …


Geological And Geochemical Analysis Of Phosphorus Bearing Minerals And Natural Glasses On Earth And In Meteorites: Implications Of The Origin Of Life, Tian Feng Jun 2021

Geological And Geochemical Analysis Of Phosphorus Bearing Minerals And Natural Glasses On Earth And In Meteorites: Implications Of The Origin Of Life, Tian Feng

USF Tampa Graduate Theses and Dissertations

Phosphorus is a key element in biogenic molecules and the mineral schreibersite is a major reactive phosphorus source for organic compounds on the prebiotic Earth. In this dissertation, a suite of reactions of phosphorus species, which originate from schreibersite minerals on chondrite meteorites and on the early Earth, have been studied to determine the intermediate geochemical pathways between phosphides and common minerals on meteorites and on the early earth.

I first investigated a unique blue fulgurite that was studied to clarify if this blue color was caused by rich phosphorus content, as has been reported for impact glasses that also …


Ware And Tear In Ancient Tampa Bay: Ceramic Elemental Analyses From Pinellas County Sites, Mckenna Loren Douglass Jun 2021

Ware And Tear In Ancient Tampa Bay: Ceramic Elemental Analyses From Pinellas County Sites, Mckenna Loren Douglass

USF Tampa Graduate Theses and Dissertations

This research tested a null hypothesis on whether ceramics from a variety of archaeological sites around the Pinellas County peninsula were sourced locally for their materials. The sites in this study include Weeden Island (8PI1-5-6-A/B/C/D), Bayshore Homes (8PI41), Yat Kitischee (8PI1753), and Maximo Point (8PI19). Since there were multiple sites that I assessed in the Tampa Bay, Florida area, I focused on one cultural period, Safety Harbor (AD 900-1500), and the ceramics created during it at the various locations. My research questions included: Were materials locally sourced for ceramic production at each of these sites? If not, what is the …


Archaeology And Seasonality Of Stock Island (8mo2), A Glades-Tradition Village On Key West, Ryan M. Harke Jun 2021

Archaeology And Seasonality Of Stock Island (8mo2), A Glades-Tradition Village On Key West, Ryan M. Harke

USF Tampa Graduate Theses and Dissertations

Later Glades-period cultures (ca. 500–1760 CE) of south Florida and the Florida Keys are understudied and thus poorly understood, especially those that pre-date the arrival of Spaniards to the New World. Recent archaeological models of their sociopolitical organization suggest that by the Glades I-II transition (750/800 CE), south Florida peoples were organized into what appear to be regional population centers (e.g., Pineland and Mound Key, Granada, Turner River) and smaller hinterland towns in the Everglades (e.g., Cane Patch, Bear Lake) and the Florida Keys (e.g., Stock Island, Clupper Site). Smaller towns are hypothesized to be sedentary, heterarchically-organized, simple chiefdoms from …


Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman May 2021

Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman

USF Tampa Graduate Theses and Dissertations

The East Antarctic Ice Sheet (EAIS) contains ~53 meters of sea level equivalent (SLE) ice, and observations suggest it is sensitive to ongoing and past climate change. The EAIS has traditionally been considered insensitive to climate perturbations because it is largely grounded above sea level. However, aerogeophysical surveys, oceanographic observations, and models indicate that large areas of the EAIS are grounded below sea level and contain 19.2 m SLE. Marine-based parts of the EAIS are thought to be located on inland-sloping beds that drain through marine terminating outlet glaciers, indicating large areas of the EAIS may be more sensitive to …


The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. Mcfarlane May 2021

The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Here we addressed the question of whether burning of guano produces a characteristic suite of morphological changes and/or unique mineralogical products. The changes observed in our experimental burning of guano (both fresh and decayed) included colour change (blackening), grain size and morphological change (grain size generally reduced, morphology rendered generally less distinct), alteration of minerals by dehydration (e.g., gypsum to anhydrite, brushite to whitlockite), and production of new minerals or compounds (e.g., augelite, bayerite, giniite, graphite, oldhamite, strontium apatite, tridymite). The key morphological feature we found that may be diagnostic of burning was severe damage to crystals from rapid dehydration …


On The Genesis Of Aluminum-Rich Speleothems In A Granite Cave Of Nw Spain, Jorge Sanjurjo-Sanchez, Carlos Arce Chamorro, Juan Ramón Vidal Romaní, Marcos Vaqueiro-Rodríguez, Victor Barrientos, Joeri Kaal Feb 2021

On The Genesis Of Aluminum-Rich Speleothems In A Granite Cave Of Nw Spain, Jorge Sanjurjo-Sanchez, Carlos Arce Chamorro, Juan Ramón Vidal Romaní, Marcos Vaqueiro-Rodríguez, Victor Barrientos, Joeri Kaal

International Journal of Speleology

Granite massifs often contain caves, with dimensions ranging from a few meters up to 1,000 m, also referred to as pseudokarst. The speleothems in such caves are mostly composed of either Si-rich (commonly opal-A) or Al-rich authigenic mineraloids. Whereas the formation and geochemical composition of opal-A biospeleothems have been studied and are fairly well understood, knowledge on the Al-rich analogues is scarce. This work reports for the first time a study on the composition, accretion process, age and growth rate of an Al-rich speleothem type flowstone from the A Trapa Cave System (Galicia, NW Spain), developed in a granite cave. …


Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella Nov 2020

Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella

USF Tampa Graduate Theses and Dissertations

Warm, intermediate-depth Southern Ocean waters are implicated in recent Antarctic ice mass loss. Direct observations of Antarctic Ice Sheet (AIS) retreat are temporally limited, necessitating paleoceanographic records of ocean-ice interactions during past warm climate intervals. Deepsea and ice-proximal sediments record orbitally-paced glacial-interglacial fluctuations in AIS volume during the Plio-Pleistocene (last 5 million years; Ma), but the total contribution of the AIS and the role of ocean heat in these fluctuations remain unresolved. To address the response of Antarctica’s ice sheets to changing ocean temperatures during the Plio-Pleistocene, International Ocean Discovery Program (IODP) Expedition 374 recovered sediments from the Ross Sea …


Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean, Brent A. Summers Jun 2020

Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean, Brent A. Summers

USF Tampa Graduate Theses and Dissertations

Iron (Fe), used as a cofactor in nitrogen fixation and photosynthesis by oceanic microorganisms, has extremely low dissolved concentrations in the surface ocean, leading to widespread limitation of phytoplankton growth. Dissolved Fe isotope ratios (δ56Fe) have been shown to be useful in helping to quantify the sources and cycling of Fe in the oceans if Fe source signatures and fractionation processes are well understood. Here, this thesis presents data from GEOTRACES section GA10W, and investigate the isotopic signature of sediment-derived dissolved Fe from the South Atlantic margins. My results show that there are both shallow (δ56Fe of -0.2‰) and deep …


Active Growth Of Non-Hydrothermal Subaqueous And Subaerial Barite (Baso4) Speleothems In Lechuguilla Cave (New Mexico, Usa), Max Wisshak, Hazel A. Barton, Katey E. Bender, Harvey R. Duchene Jan 2020

Active Growth Of Non-Hydrothermal Subaqueous And Subaerial Barite (Baso4) Speleothems In Lechuguilla Cave (New Mexico, Usa), Max Wisshak, Hazel A. Barton, Katey E. Bender, Harvey R. Duchene

International Journal of Speleology

Barite (BaSO4) speleothems have been reported from caves around the globe and interpreted to have chiefly formed in phreatic, hypogene, hydrothermal settings. Here we report two contrasting types of barite speleothems (bluish tabular crystals in a shallow pool and actively dripping greenish stalactites), which today form at lower temperatures in the non-hydrothermal and vadose environment of Lechuguilla Cave, New Mexico, USA. Scanning electron microscopy analysis, along with energy- and wavelength-dispersive X-ray spectroscopy (EDS, WDS), as well as X-ray diffraction (XRD), characterize the habit and chemical composition as barite. Fractionation of the minor element calcium is related to growth …


Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward Nov 2019

Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward

USF Tampa Graduate Theses and Dissertations

North of Martinique island the Lesser Antilles volcanic arc bifurcates, creating a double arc. Here volcanic activity has migrated up to 50 km westward with time, resulting in two volcanic lines that are distinct in age. The eastern line, commonly referred to as the old arc, was active from Early Eocene to Mid-Miocene (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., 1988). The western line, commonly referred to as the recent arc, has been active since the late Pliocene, ~6 Ma ago (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., …


On The Ablation Of Meteors And The Implications On Organic Delivery To Earth, Christopher Alan Mehta Oct 2019

On The Ablation Of Meteors And The Implications On Organic Delivery To Earth, Christopher Alan Mehta

USF Tampa Graduate Theses and Dissertations

The synthesis of prebiotic organic compounds is a key step in the origin of life. Sources of these materials are divided into endogenous and exogenous sources. Endogenous synthesis—occurring potentially on the surface of the Earth—includes such historic experiments as the Miller spark discharge and formose chemistry. However, one avenue for exogenous synthesis to occur is when meteors enters an atmosphere. Using principles of orbital mechanics, geology, physics, and chemistry, we study meteor ablation and the transport of organic matter to the surface of Earth. To do so, I create numerical models that simulates meteors traveling through the atmosphere of Earth …


Genesis Of Iron And Manganese Sediments In Zoloushka Cave (Ukraine/Moldova) As Revealed By Δ13C Organic Carbon, Piotr Kotula, Viacheslav Andreychouk, Jacek Pawlyta, Leszek Marynowski, Izabela Jendrzejewska Sep 2019

Genesis Of Iron And Manganese Sediments In Zoloushka Cave (Ukraine/Moldova) As Revealed By Δ13C Organic Carbon, Piotr Kotula, Viacheslav Andreychouk, Jacek Pawlyta, Leszek Marynowski, Izabela Jendrzejewska

International Journal of Speleology

Zoloushka Cave is one of the largest maze gypsum caves in the world. Mining of the gypsum bedrock and lowering of the water level due to the pumping of groundwater led to exposure of the cave passages to vadose conditions and changed the hydrochemistry of the karst water. As a result, large quantities of Fe and Mn hydroxides were deposited in the passages. It was found that at least two groups of various organisms were involved in depositing ferrous and manganese sediments. In order to establish the mechanism of deposition, we conducted chemical analyses of the sediments and isotopic analyses …


Fluid-Mobile Trace Element Variability Of Serpentinites And Entrained Crustal Rocks Across The Mariana Forearc System, Raymond M. Johnston Aug 2019

Fluid-Mobile Trace Element Variability Of Serpentinites And Entrained Crustal Rocks Across The Mariana Forearc System, Raymond M. Johnston

USF Tampa Graduate Theses and Dissertations

In the Mariana subduction system, active serpentinite mud volcanoes are associated with the subduction of the Pacific plate beneath the Philippine plate in a non-accretionary convergent plate margin. This location offers a unique opportunity to study the subduction zone interface with little crustal contamination. The systematics of fluid-mobile trace elements (FME) (As, Cs, Rb, Sb, Tl, Pb, and Sr) in erupted serpentinite muds and entrained serpentinized ultramafic and mafic clasts can place constraints on the release of slab-derived fluids from the downgoing plate, and ultimately the pressure/temperature (P/TC°) conditions at which these fluids are mobilized.

The samples analyzed in this …


Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan Jul 2019

Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan

USF Tampa Graduate Theses and Dissertations

Mollusks grow by adding discrete growth layers throughout their lifetime (i.e., accretion). More specifically, most marine mollusks precipitate their shells in oxygen isotopic equilibrium with seawater or with a constant offset from equilibrium. The stable oxygen isotope values (δ18O) of their shells are determined by the temperature and δ18O values of the surrounding water during calcification without significant vital effects. In comparison, the stable carbon isotope values (δ13C) of their shells reflect those of the dissolved inorganic carbon (δ13C- DIC) and respired carbon dioxide. Therefore, variations in the oxygen and carbon isotope …


Morphological And Mineralogical Evidence For Ancient Bat Presence In Cova Des Pas De Vallgornera (Llucmajor, Mallorca, Western Mediterranean), Antoni Merino, Joan J. Fornós, Antoni Mulet, Joaquín Ginés May 2019

Morphological And Mineralogical Evidence For Ancient Bat Presence In Cova Des Pas De Vallgornera (Llucmajor, Mallorca, Western Mediterranean), Antoni Merino, Joan J. Fornós, Antoni Mulet, Joaquín Ginés

International Journal of Speleology

Cova des Pas de Vallgornera is a unique karst cave located at the Llucmajor coastal platform that stands out not only because of its length, more than 78 km, but also for its particular morphological suite, richness and variety of speleothems and mineral infillings. Although the mineralogy of speleothems and minerals related to hypogene morphologies has been studied and described, the existence of minerals derived from guano deposits was still poorly investigated. The cave hosted bat colonies until the collapse of its natural entrances, circa 2.4 My ago, since then until its discovery in 1968, the cave remained sealed. These …


Variations Of Sedimentary Biogenic Silica In The Gulf Of Mexico During The Deepwater Horizon And Ixtoc-I Oil Spill., Jong Jin Lee Mar 2019

Variations Of Sedimentary Biogenic Silica In The Gulf Of Mexico During The Deepwater Horizon And Ixtoc-I Oil Spill., Jong Jin Lee

USF Tampa Graduate Theses and Dissertations

The goal of this research is to understand the impacts of the 2010 Deepwater Horizon oil spill and the 1970-1980 IXTOC-I oil spill and other anthropogenic activity (e.g. dam construction) on surface water primary productivity by measuring sedimentary biogenic silica. It is known that sedimentary biogenic silica is distinct from mineral – bound silica, therefore it has been used as a proxy record for surface water primary productivity (e.g. diatom blooms). The Deepwater Horizon oil spill resulted in a widespread Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. The IXTOC-I oil spill was one of the largest oil spills …


Assessing Paleo-Coastal Caves Evolution And Sea Level Changes In Mallorca: Results From Radiometric Dating Of Speleothems, Giuseppe Lucia Mar 2019

Assessing Paleo-Coastal Caves Evolution And Sea Level Changes In Mallorca: Results From Radiometric Dating Of Speleothems, Giuseppe Lucia

USF Tampa Graduate Theses and Dissertations

Sea level affects the littoral morphology and structure in different ways. In coastal karst basins, dissolutional and depositional processes are strictly related to sea level variation. A great variety of karst-related geomorphological features and cave deposits exist above, below, and at sea level, and are extremely useful to study past changes of relative sea level. Within these, vadose speleothems such as flowstones and stalagmite, can document unequivocal maximum sea level constraints as well as record phreatic phases of sea level rise. Here we present a series of geochronological data from the eastern Mallorca and show the implication of relative sea …


Cave Dripwater Isotopic Signals Related To The Altitudinal Gradient Of Mount-Lebanon: Implication For Speleothem Studies, Carole Nehme, Sophie Verheyden, Fadi H. Nader, Jocelyne Adjizian-Gerard, Dominique Genty, Kevin De Bont, Benedicte Minster, Ghada Salem, David Verstraten, Philippe Clayes Mar 2019

Cave Dripwater Isotopic Signals Related To The Altitudinal Gradient Of Mount-Lebanon: Implication For Speleothem Studies, Carole Nehme, Sophie Verheyden, Fadi H. Nader, Jocelyne Adjizian-Gerard, Dominique Genty, Kevin De Bont, Benedicte Minster, Ghada Salem, David Verstraten, Philippe Clayes

International Journal of Speleology

An important step in paleoclimate reconstructions based on vadose cave carbonate deposits or speleothems is to evaluate the sensitivity of the cave environment and speleothems to regional climate. Accordingly, we studied four caves, located at different altitudes along the western flank of Mount-Lebanon (Eastern Mediterranean). The objectives of this study are to identify the present-day variability in temperature, pCO2, and water isotopic composition and to assess the possible influence of the altitudinal gradient on cave drip waters and cave streams. We present here an overview of the spatial variability of rainwater based on local and regional data, and …


Isolution 1.0: An Isotope Evolution Model Describing The Stable Oxygen (Δ18O) And Carbon (Δ13C) Isotope Values Of Speleothems, Michael Deininger, Denis Scholz Jan 2019

Isolution 1.0: An Isotope Evolution Model Describing The Stable Oxygen (Δ18O) And Carbon (Δ13C) Isotope Values Of Speleothems, Michael Deininger, Denis Scholz

International Journal of Speleology

Stable oxygen and carbon isotope ratios (δ13C and δ18O) are the most applied climate and environmental proxies in speleothems allowing to infer past changes in cave drip water δ13C and δ18O related to climate and environmental variations from above the cave. However, disequilibrium isotope fractionation processes can modify δ13C and δ18O values in speleothems, which is in most cases difficult to estimate due to inter-dependencies on various cave specific parameter. To better understand the effect of these disequilibrium isotope fractionation processes proxy system models were developed in recent …