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Sub-Recent Microfauna Within Allogenic Sediments At The Bottom Of A Deep Cave, Njemica (Biokovo Mt., Croatia), Tomislav Kurečić, Valentina Hajek Tadesse, Lara Wacha, Marija Horvat, Nina Trinajstić, Ivan Mišur Nov 2022

Sub-Recent Microfauna Within Allogenic Sediments At The Bottom Of A Deep Cave, Njemica (Biokovo Mt., Croatia), Tomislav Kurečić, Valentina Hajek Tadesse, Lara Wacha, Marija Horvat, Nina Trinajstić, Ivan Mišur

International Journal of Speleology

Clastic sediments deposited at the bottom of the vertical, nearly 1000 m deep Njemica Cave (Biokovo Mountain, Croatia) were analysed. Owing to the vertical morphology of the cave, the occurrences of clastic sediments are sparse. Small, up to decimetre-thick, undisturbed sediment accumulations situated near the siphon lake revealed interesting palaeontological and mineralogical data. These data are used as a useful proxy for discussing depositional processes, the provenance of the sediments and paleo-habitats of the subterranean fauna.

The sub-recent assemblages of ostracods were discovered within the sediment, and they were shown to be correlative to the known endemic species in the …


Volcano And Tectonic Hazard Modeling Using Interdisciplinary Geophysical And Geodetic Methods, Mitchell Scott Hastings Nov 2022

Volcano And Tectonic Hazard Modeling Using Interdisciplinary Geophysical And Geodetic Methods, Mitchell Scott Hastings

USF Tampa Graduate Theses and Dissertations

Volcanic and tectonic hazards such as volcanic eruptions, earthquakes and tsunamis present risks to about ~45% of the global population. They have caused at least 1.5 trillion dollars in damages worldwide since the start of the 20th century, and the costs are accelerating as population increases. In this dissertation, new data are combined with existing information and novel modeling approaches to quantify volcanic, earthquake and tsunami hazards.

The Blackfoot Reservoir Volcanic Field (BRVF) is a bimodal volcanic field on southeastern margin of the Eastern Snake River Plain in Idaho. In the BRVF, gravity anomalies reveal two shallow silicic intrusions that …


Flow Regime Evolution Of A Major Cave System In The Eastern Alps (Hirlatzhöhle, Dachstein), Lukas Plan, Gottfried Buchegger, Eva Kaminsky, Gabriella Koltai, Tanguy Racine, Jacek Szczygieł Oct 2022

Flow Regime Evolution Of A Major Cave System In The Eastern Alps (Hirlatzhöhle, Dachstein), Lukas Plan, Gottfried Buchegger, Eva Kaminsky, Gabriella Koltai, Tanguy Racine, Jacek Szczygieł

International Journal of Speleology

The 116 km-long and 1560 m-deep Hirlatzhöhle is one of the major cave systems in the Northern Calcareous Alps (NCA; Austria). It is located in the NW part of the Dachstein, an extensive karst massif encompassing 576 km² with its highest point at 2995 m a.s.l. In contrast to most other caves in the NCA, Hirlatzhöhle comprises old (epi)phreatic passages located up to 1 km above the base level as well as two modern major drainage systems. The aim of this study is to define the palaeo- and the active flow conditions in combination with speleogenesis, and the age of …


Airflow Dynamics In Wind Cave And Jewel Cave: How Do Barometric Caves Breathe?, Annika K. Gomell, Andreas Pflitsch Oct 2022

Airflow Dynamics In Wind Cave And Jewel Cave: How Do Barometric Caves Breathe?, Annika K. Gomell, Andreas Pflitsch

International Journal of Speleology

Recent research on air pressure propagation through barometric caves has revealed various speleoclimatological processes, which cause a more complex relationship between surface air pressure changes and resulting pressure gradients between cave and surface air than previously assumed. So far, however, studies on barometric cave airflow have only been based on surface air pressure measurements. Thus, this study investigates and compares airflow at the openings of Wind Cave and Jewel Cave – two major barometric cave systems in South Dakota, USA – as a response to surface air pressure changes and air pressure gradients. Based on high-resolution long-term air pressure measurements …


Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová Sep 2022

Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová

International Journal of Speleology

A variety of speleothems are present in crevice and boulder caves developed in Cretaceous sandstones of the Elbe River Canyon in northern Czech Republic. A set of complementary instrumental mineralogical methods was applied to characterize the speleothems and cave dripwaters, including X-ray powder diffraction, scanning electron microscopy and microanalysis, Raman spectroscopy and optical emission spectrometry. Four morphological types were distinguished and characterized in terms of their mineral and chemical composition: 1, rusty brown mud-dominated coatings with micro-gours, composed of a mixture of clay minerals; 2, white “chalky” coatings (moonmilk) composed of calcite with minor gypsum; 3, cauliflower-shaped coralloids composed of …


Functional Morphology And Taphonomy Of Ordovician–Silurian Diploporan Echinoderms, Stephen Ashley Hill Jul 2022

Functional Morphology And Taphonomy Of Ordovician–Silurian Diploporan Echinoderms, Stephen Ashley Hill

USF Tampa Graduate Theses and Dissertations

Diploporan echinoderms were one of the most speciose groups of stemmed echinoderms during the Ordovician. Despite this widespread abundance, the fossil record of diploporan fauna consists primarily of incomplete specimens, with complete specimens being rare. While the theca, or body, is more commonly preserved, the feeding appendages and the attachment structures (i.e. stems or holdfasts) are seldomly preserved. Insight into these features is highly valuable to the understanding the paleoecology, like the feeding and respiratory strategies, of these enigmatic creatures.

One group of diploporan echinoderms which does have an extensive fossil record, is the Holocystites Fauna, primarily known from the …


Sulfuric Acid Speleogenesis And Surface Landform Evolution Along The Vienna Basin Transfer Fault: Plavecký Karst, Slovakia, Pavel Bella, Helena Hercman, Šimon Kdýr, Petr Mikysek, Petr Pruner, Juraj Littva, Jozef Minár, Michal Gradzinski, Wojciech Wróblewski, Marek Velšmid, Pavel Bosak Jul 2022

Sulfuric Acid Speleogenesis And Surface Landform Evolution Along The Vienna Basin Transfer Fault: Plavecký Karst, Slovakia, Pavel Bella, Helena Hercman, Šimon Kdýr, Petr Mikysek, Petr Pruner, Juraj Littva, Jozef Minár, Michal Gradzinski, Wojciech Wróblewski, Marek Velšmid, Pavel Bosak

International Journal of Speleology

Hypogene caves in the Plavecký hradný vrch Hill (Western Slovakia, Central Europe) were formed by waters ascending along faults in fractured Triassic carbonates related to the horst-graben structure at the contact of the Malé Karpaty Mountains and the NE part of the Vienna Basin. The Plavecká jaskyňa and Pec caves mostly contain horizontal passages and chambers with flat corrosion bedrock floors, fissure discharge feeders, wall water-table notches, replacement pockets, as well as a few other speleogens associated with sulfuric acid speleogenesis. The low-temperature sulfuric acid development phases of the Plavecká Jaskyňa are also indicated by the presence of sulfate minerals …


Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins Jun 2022

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‰) …


A Technique-Based Approach To Structure-From-Motion: Applications To Human-Coastal Environments, Robert Van Alphen Jun 2022

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 …


Determining Depth Of Closure Based On Time-Series Beach Profiles And Empirical Formulas: A Case Study Along The Florida Coast, Elizabeth Royer Jun 2022

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 …


Characterizing Explosive Volcanic Eruptions Using Tephra Fall Deposit Data, Robert Constantinescu Mar 2022

Characterizing Explosive Volcanic Eruptions Using Tephra Fall Deposit Data, Robert Constantinescu

USF Tampa Graduate Theses and Dissertations

This dissertation addresses the estimation of the magnitudes and intensities of explosive volcanic eruptions using tephra fall deposits and numerical modeling. Tephra fall deposits retain information about eruption dynamics. Volcanologists sample tephra fall deposits and measure the thickness, extent and grain size distribution to estimate the erupted volume and plume height of explosive eruptions. These terms are known as eruption source parameters. These parameters are used to classify the intensity and magnitude of the eruption on a scale such as the Volcanic Explosivity Index (VEI). Accurate estimation of the intensity and magnitude of explosive eruptions is a crucial factor in …