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Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti 2017 University of Bologna

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an ...


Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele 2017 University of Bologna

Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele

International Journal of Speleology

Detailed petrographic observations have been coupled with trace element and δ13C - δ18O analyses in order to investigate their dynamics in two Holocene Bosnian speleothems. The potential of this multiproxy approach in providing a means to extract palaeo-environmental information from stalagmites whose stable isotope signals are noisy and without obvious trends has been tested. The studied stalagmites are mostly characterized by columnar microcrystalline fabric. At the sub-millimetre scale of lamination, different microcrystalline columnar sub-types (open and closed) have been detected and classified on the basis of the observed porosity and the crystallite size. The presence of variations ...


The Ribbed Drapery Of The Puerto Princesa Underground River (Palawan, Philippines): Morphology And Genesis, Paolo Forti, Giovanni Badino, Jose Maria Calaforra, Jo De Waele 2016 Italian Institute of Speleology

The Ribbed Drapery Of The Puerto Princesa Underground River (Palawan, Philippines): Morphology And Genesis, Paolo Forti, Giovanni Badino, Jose Maria Calaforra, Jo De Waele

International Journal of Speleology

During the 2011 speleological expedition to the Puerto Princesa Underground River (Palawan, Philippines) a drapery characterized by several close-to-horizontal ribs has been noticed. Even without sampling and analyzing its internal growth layers, a detailed morphological study allowed to present a possible genetic model. The presented model helps to explain its evolution, which is mainly controlled by variation in water flow as a consequence of the Palawan climate. When validated by further analyses, the same genetic mechanism could define also the evolution of the very common but still unexplained complex flowstones, which exhibit several close-to-horizontal steps, widenings and narrowings along their ...


An Investigation Into The Origin, Composition, And Commercial Significance Of A Sedimentary Subsalt Formation: Keathley Canyon, Gulf Of Mexico, David Aaron Brassieur 2016 University of New Orleans, New Orleans

An Investigation Into The Origin, Composition, And Commercial Significance Of A Sedimentary Subsalt Formation: Keathley Canyon, Gulf Of Mexico, David Aaron Brassieur

University of New Orleans Theses and Dissertations

Sub-salt oil and gas formations in deep-water northern Gulf of Mexico are high priority targets. Advances in seismic processing allow for high-resolution, below-salt imaging. Understanding the modes of salt emplacement provide insight into sub-salt traps and potential drilling hazards.

A sub-salt sedimentary unit lies in the Keathley Canyon protraction. Autosutures created the transport-parallel lineaments of the upper surface of the unit. In addition, highly variable sediment aggradation rates created ramps, flats, and basal cutoffs along the base of the allochthon as salt and sediment competed for space. Seismic models identify modes of salt emplacement, salt/sediment interactions, and mechanisms responsible ...


Biloxi Marsh Platform Response Due To Meteorological Forcing, Rachelle Thomason 2016 University of New Orleans

Biloxi Marsh Platform Response Due To Meteorological Forcing, Rachelle Thomason

University of New Orleans Theses and Dissertations

The Biloxi Marsh of the eastern Mississippi River delta plain is exposed to meteorological forces ranging from large-scale, mid-latitude cyclones to smaller scale storms and squalls. Each time that these marsh platforms are exposed to a storm event, the potential exists for either deposition or erosion to take place. This study examines the connection between wind speeds, stratigraphic composition, marsh edge morphology, and marsh edge erosion at 4 sites in the Biloxi Marsh. As much as 2.17 m of erosion were measured during the 9-month study with a maximum, averaged erosion rate of 0.03 m day-1. Shell ...


Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub 2016 Stephen F Austin State University

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas ...


Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann 2016 University of Southern Mississippi

Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann

Master's Theses

The Mississippi – Alabama barrier island chain is experiencing accelerated sea level rise, decreased sediment supply, and frequent hurricane impacts. These three factors drive unprecedented rates of morphology change and ecosystem reduction. All islands in the chain have experienced land loss on the order of hectares per year since records began in the 1840s. In 1969, Hurricane Camille impacted as a Category 5, breaching Ship Island, and significantly reduced viable seagrass habitat. Hurricane Katrina impacted as a Category 3 in 2005, further widening Camille Cut. To better understand the sustainability of these important islands and the ecosystems they support, sediment transport ...


The Morphology And Development Of Kalahroud Cave, Iran, Shirin Bahadorinia, Sayed Hassan Hejazi, Alireza Nadimi, Derek C. Ford, Karine Wainer 2016 Islamic Azad University, Esfahan

The Morphology And Development Of Kalahroud Cave, Iran, Shirin Bahadorinia, Sayed Hassan Hejazi, Alireza Nadimi, Derek C. Ford, Karine Wainer

International Journal of Speleology

Kalahroud Cave is located in central Iran, ~50 km north of Isfahan. The landscape is a typical mountain desert morphology of cuestas dissected by ravines and gorges created during rare surface run-off events; crest lines are ~2800 m asl and lowlands at ~2100 m asl. Kalahroud Cave (4500 m of mapped passages, ~60 m deep) is entered through breakdown in the eastern wall of a gorge. The host rock is a Cretaceous limestone and mudstone formation 60 m in thickness, underlain by sandstones and conglomerates and overlain by weakly permeable calcareous marl strata, all dipping 15-20o. Below the entrance ...


Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen 2016 The Graduate Center, City University of New York

Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

Rainfall-induced landslides are one of the most frequent hazards on slanted terrains. They lead to considerable economic losses and fatalities worldwide. Intense storms with high-intensity and long-duration rainfall have high potential to trigger rapidly moving soil masses due to changes in pore water pressure and seepage forces. Nevertheless, regardless of the intensity-duration of the rainfall, shallow landslides are influenced by antecedent soil moisture conditions. To the present day, no system exists that dynamically interrelates these two factors.

This work establishes a relationship between antecedent soil moisture and rainfall expressed in the form of a Shallow Landslide Index (SLI) at 1km ...


Birth And Evolution Of The Rio Grande Fluvial System In The Last 8 Ma:Progressive Downward Integration And Interplay Between Tectonics, Volcanism, Climate, And River Evolution, Marisa N. Repasch 2016 University of New Mexico

Birth And Evolution Of The Rio Grande Fluvial System In The Last 8 Ma:Progressive Downward Integration And Interplay Between Tectonics, Volcanism, Climate, And River Evolution, Marisa N. Repasch

Earth and Planetary Sciences ETDs

The Rio Grande-Rio Chama (RG-RC) fluvial system has evolved dramatically over the last 8 Ma, undergoing channel migrations, drainage capture and integration events, volcanic damming, and carving and refilling of paleocanyons. Volcanism concurrent with the development of the river system provides a unique opportunity to apply multiple geochronometers to the study of its incision and drainage evolution. This paper reports 19 new 40Ar/39Ar basalt ages and 19 detrital mineral samples (zircon and sanidine) collected from RG-RC alluvium overlain by dated basalt flows in the context of a compilation of published 40Ar/39Ar basalt ages. The ...


Is Coral Community Structure Linked To Damage Susceptibility? A Case Study From South Africa, Bernhard Riegl, Peter A. Cook 2016 Institut fur Palaontologie der Universitat Wien

Is Coral Community Structure Linked To Damage Susceptibility? A Case Study From South Africa, Bernhard Riegl, Peter A. Cook

Bernhard Riegl

Africa's southernmost coral communities are situated in northern Natal, South Africa (27°50' S), within the Maputaland and St. Lucia Marine Reserves. Growing concern about the possible impact of recreational acti vities on the health of the coral ecosystem prompted the present study on the structure and health of the reefs. Coral community studies by means of line transects identified three basic coral community types, which correlated with the geomorphology of the sandstone outcrops on which corals grew. 1) Fossil dunes were dominated by alcyonacea in depths between 8 and 24 m. 2) Flat outcrops between 18 and 24 ...


Martian Gully Formation And Evolution: Studies From The Local To Global Scale, Tanya Nicole Harrison 2016 The University of Western Ontario

Martian Gully Formation And Evolution: Studies From The Local To Global Scale, Tanya Nicole Harrison

Electronic Thesis and Dissertation Repository

Gullies in the mid- and high-latitudes of Mars were first observed in Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images in 1997. Appearing to be geologically young, they quickly became a feature of interest due to the implication of liquid water in their formation based on distinct morphological characteristics including incised channels, many exhibiting features indicative of fluid flow. However, the temperature and pressure conditions on the surface of Mars during its most recent geologic era have not been conducive to sustaining water in the liquid phase for extended periods of time; therefore, a number of “wet” (water-related) and ...


Sediment Accumulations Patterns In The Damariscotta River Estuary, Emily A. Chandler 2016 University of Maine

Sediment Accumulations Patterns In The Damariscotta River Estuary, Emily A. Chandler

Electronic Theses and Dissertations

The tidally dominated Damariscotta River estuary is located on the south-central Maine coast. The elongate, north-south orientation of the estuary is characteristic of the indented shoreline in this region and a consequence of the bedrock structural framework, comprised of Paleozoic high-grade metasedimentary rocks. Pegmatite sills form bedrock constriction points that divide the estuary into seven distinct basins. The narrow, bending geometry and sill and basin morphology impact the distribution of sediment within the estuary and the hydrodynamics of the system. This study employs multibeam bathymetry surveys, sediment grab samples and radionuclide analysis (210Pb and 137Cs) of sediment cores ...


Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston 2016 University of Maine

Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston

Electronic Theses and Dissertations

Dam removals from the Penobscot River in Maine restored access to freshwater habitat critical for the life cycle of endangered shortnose sturgeon. Prior to the dam removals, shortnose sturgeon spawning activity had not been documented. Instead, evidence suggested that individuals emigrated from the Penobscot River to spawn in the Kennebec complex, 140 km away. A central question of this thesis was whether spawning activity would commence in the first two years following dam removal. Consistent with pre-dam removal movement patterns determined using acoustic telemetry, the majority (78%) of tagged individuals emigrated from the Penobscot River at some point over the ...


Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy 2016 University of Southern Mississippi

Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy

Master's Theses

The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a ...


Reevaluating The Geologic Formations Of The Upper Coastal Plain In Chesterfield County, South Carolina, Bradley Aaron Fitzwater 2016 Old Dominion University

Reevaluating The Geologic Formations Of The Upper Coastal Plain In Chesterfield County, South Carolina, Bradley Aaron Fitzwater

OEAS Theses and Dissertations

Data from a new geological map of the Patrick, S.C. 7.5 minute quadrangle (1:24,000) and detailed descriptions of two cores collected nearby (Middendorf and Cheraw, S.C.) permit improved interpretation of the geology of this portion of the Carolina Sandhills. Geologic mapping incorporated analyses of outcrops with LiDAR data, soil survey maps, ground-penetrating radar transects, and hand auger borings. Micro- and macrofossil identification and optically-stimulated luminescence (OSL) dating provided age control.

Four distinct mappable units occur throughout the Patrick quadrangle. Resting unconformably on schist of the Paleozoic Persimmons Fork Formation, the Cretaceous Middendorf Formation is more ...


The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu 2016 University of Nebraska - Lincoln

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Papers in the Earth and Atmospheric Sciences

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover ...


The Spatial Distribution And Origins Of Sandstone Monoliths In The Swauk Watershed, Kittitas County, Wa, Rebeca Becerra, Daniel O'Dell 2016 CWU

The Spatial Distribution And Origins Of Sandstone Monoliths In The Swauk Watershed, Kittitas County, Wa, Rebeca Becerra, Daniel O'Dell

Symposium Of University Research and Creative Expression (SOURCE)

Large groups of gigantic sandstone and conglomerate monoliths populate the Swauk Watershed of northern Kittitas County. These monoliths rest on side slopes in the watershed and distinctively project from their surroundings. The origins of these features are unknown. We studied these monoliths in the field by mapping their spatial distribution, describing their morphology and composition, and measuring their orientation and sizes in order to determine their origins. We used Google Earth and topographic maps to locate the monoliths and map their distribution. Interpretations were based from field work data and past research. Our field results show commonalities between the features ...


Barrier Spit Evolution And Primary Consolidation Of Backbarrier Facies: West Belle Pass Barrier, La, John N. Kramer III 2016 University of New Orleans, New Orleans

Barrier Spit Evolution And Primary Consolidation Of Backbarrier Facies: West Belle Pass Barrier, La, John N. Kramer Iii

University of New Orleans Theses and Dissertations

West Belle Pass Barrier is a barrier spit that formed during the last delta lobe progradation associated with the Lafourche delta complex. Located on the western flank of the Caminada-Moreau Headland, West Belle Pass Barrier and Raccoon Pass are located downdrift of the Belle Pass jetties. Morphological changes stemming from storms, jetty infrastructure, and an expanding tidal inlet are evaluated using historical shoreline data and imagery. Littoral transport around the jetties combined with inlet growth created a framework wherein sediment is transported through Raccoon Pass and sequestered as a flood-tidal delta. These events aided in the landward migration of West ...


Search For An Artificially Buried Karst Cave Entrance Using Ground Penetrating Radar: A Successful Case Of Locating The S-19 Cave In The Mt. Kanin Massif (Nw Slovenia), Andrej Gosar, Teja Čeru 2016 University of Ljubljana

Search For An Artificially Buried Karst Cave Entrance Using Ground Penetrating Radar: A Successful Case Of Locating The S-19 Cave In The Mt. Kanin Massif (Nw Slovenia), Andrej Gosar, Teja Čeru

International Journal of Speleology

The S-19 Cave was with its explored depth of 177 m one of the most important caves of the Mt. Kanin massif, but after its discovery in 1974, a huge snow avalanche protection dyke was constructed across the cave entrance. To excavate the buried cave, the accurate location of the cave had to be determined first. Since the entrance coordinates were incorrect and no markers were available, application of geophysical techniques was necessary to do this. A Ground Penetrating Radar (GPR) with special 50 MHz rough terrain antennas was selected as the single suitable geophysical method for the given conditions ...


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