Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), 2017 Universidad de Zaragoza
Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera
International Journal of Speleology
Evaluation of karst hazards benefits from the integration of different techniques, methodologies and approaches. Each one presents a different signature and is sensitive to certain indicators related to karst hazards. In some cases, detailed analysis permits the evaluation of representativeness either from isolated approaches or by means of integrated analyses. In this study, we present the evaluation of an area with high density of karstic collapses at different evolutionary stages through the integration of surficial, historical, geomorphological and geophysical data in order to finally define the evolutionary model for karst activity development. The obtained dataset permits to identify different steps ...
Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz De La Torre
International Journal of Speleology
The geomorphological characteristics and hydrogeological functioning of a geologically heterogeneous evaporitic karst plateau in Southern Spain were studied. Land surface information (LiDAR data) was used to analyze the shape and distribution of closed depressions. An artificial tracer test and monitoring of the natural responses of the main spring have allowed to infer the karstic development of the studied system. Three dyes were injected in selected swallow holes to trace the main groundwater flowpaths and to estimate the dimension of the conduit network. Discharge, electrical conductivity and temperature were monitored in the groundwater that drains the evaporitic plateau during an individual ...
Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, 2017 Polytechnic University of Turin
Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele
International Journal of Speleology
A Messinian succession containing gypsum beds crops out in northern Italy, mainly in Piedmont and along the northern flank of the Apennine mountains in Emilia-Romagna. These gypsum bodies have been extensively quarried at the surface, in outcrops, and through underground quarries. In Emilia-Romagna these gypsum outcrops can be rather extensive, several km long and up to 1 km wide, while in Piedmont they are mostly covered by silty-marly deposits of Upper Messinian and Pliocene age and show only sparse and small outcrops. The underground quarrying of these evaporite bodies in Piedmont has allowed studying in detail their hydrogeology, and the ...
Sedimentology And Taphonomy Of The Abydosaurus Mcintoshi Quarry, (Naturita Formation, Early Cretaceous, Latest Albian), Dinosaur National Monument, Utah, Aaron Daniel Holmes
All Theses and Dissertations
The holotypic locality of the brachiosaurid titanosauriform sauropod, Abydosaurus mcintoshi, is quarry DNM-16, located in Dinosaur National Monument. The bones are preserved near the base of a heterolithic, trough cross stratified to planar bedded sandstone channel complex. The trough cross to planar bedded sandstones mark times of variable flow with times of high flow velocity based on bones whose upper surfaces were eroded before final burial. The abundance of mud with the dominant medium to fine sand, and poorly confined sandstone channels indicate the bones were transported and buried in medial to distal intermittent flows of a distributive fluvial system ...
Formation Of Rapakivi Feldspars In The Deer Isle Granite Complex, Coastal Maine: In Situ Lead Isotope And Trace Element Analysis, William Desmond Obrien
All Theses and Dissertations
Rapakivi and alkali feldspar phenocrysts from the Deer Isle Granite Complex were investigated using in situ trace element and Pb isotope geochemistry to see if magma mixing or isothermal decompression was responsible for their formation. Pb isotope and trace element profiles, along with CL imagery of quartz phenocrysts, indicate compositional changes in the magma chamber occurred during rapakivi and alkali feldspar growth. Repeated episodes of magma mixing/replenishment by relatively isotopically primitive and LREE enriched magmas (along with hybridized variations with the host magma) created localized disequilibration. Alkali feldspar phenocrysts proximal to these zones of thermal perturbation were first resorbed ...
Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), 2017 University of Nebraska - Lincoln
Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine
Conservation and Survey Division
No abstract provided.
The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, 2017 University of San Diego
The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell
In the US Virgin Islands (USVI), land-based (terrigenous) sedimentation has been identified as a major cause of coral stress. Development, such as the building of unpaved roads in steep coastal watersheds, has increased sediment yields and marine terrigenous sedimentation by up to an order of magnitude above background levels. When activated during storm events, ephemeral streams transport sediment from the watershed to coastal waters. Once deposited on the seafloor, resuspension of benthic sediments can further increase turbidity and deposition. However, isolating the relative contributions of runoff and resuspension to turbidity and deposition using conventional sediment trap monitoring has been challenging ...
Evaluating Relationships Between Rock Strength And Longitudinal Stream Profile Morphometry In The Southern Guadalupe Mountains, Texas, Samuel T. Schoenmann
Theses and Dissertations
Landscapes record information about the tectonic, climatic, and lithologic environments in which they form (Yang et al., 2015). When one or more of these environmental conditions change spatially or temporally, the landscape responds through erosion and thus, develops representative geomorphic features (Ritter et al., 2011). Since the nineteenth century, it has been clear that bedrock strength and erodibility play an important role in landscape evolution and geomorphology (Lifton et al., 2009). However, the nuances of variable erodibility remain poorly understood. The implications of this limited understanding lies within landscape evolution models. While these models show strong qualitative relationships between longitudinal ...
Overwash Controls On Barrier Island Morphodynamics During Storms, 2017 University of New Orleans
Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon
University of New Orleans Theses and Dissertations
Overwash, shoreface retreat, and barrier migration are common processes occurring in transgressive barrier island systems, the scale of which is exacerbated by sea level rise, subsidence and the frequency and magnitude of tropical and extratropical storms. Barrier morphology also clearly plays a key role in determining a morphological response to these processes. Using a hydrodynamic and sediment transport model (MIKE21) and selected barrier island and shoreface templates, informed by deltaic and coastal plain systems in the northern Gulf of Mexico, I performed simulations to determine barrier morphology in response to storms. A low dune with a gentle shoreface slope, characteristic ...
Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, 2017 The University of San Francisco
Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle
Master's Projects and Capstones
Groundwater is an integral piece of California’s groundwater resources. One of the most common contaminants present in groundwater is nitrate. Nitrate contamination is often a result of agricultural land use activities on the ground surface. The study area for this analysis is the Salinas Valley Groundwater Basin, an agriculturally dominated basin in coastal California. The Salinas Valley Basin is both one of the most agriculturally productive areas of the state, as well as one of the most nitrate-contaminated basins in the state. The purpose of this research was to develop a groundwater vulnerability map for nitrate pollution in the ...
Paleomagnetic Dating Of Fault Slip In The Southern Rocky Mountains, Usa, And Its Importance To An Integrated Laramide Foreland Strain Field, T. F. Wawrzyniec, Alexis K. Ault, J. W. Geissman, E. A. Erslev, S. D. Fankhauser
The Laramide orogen of the U.S. Cordillera formed in the latest Cretaceous, and deformation lasted into the earliest Oligocene. Along and proximal to the eastern and northern margins of the Colorado Plateau, deformation associated with this event mainly took place along reactivated structures. Related tectonic models invoke some role for the plateau either as a stress guide transmitting compression to the foreland or as a freely rotating microplate. Models dominated by northward displacements of the Colorado Plateau also require covariance between timing and magnitude of dextral strike-slip deformation in the eastern domain and thrust deformation in the northern domain ...
Microtextural Constraints On The Interplay Between Fluidrock Reactions And Deformation, 2017 Utah State University
Microtextural Constraints On The Interplay Between Fluidrock Reactions And Deformation, Alexis K. Ault, Jane Selverstone
Schists from two mylonitic localities in the footwall of a low-angle normal fault in the eastern Alps record different degrees of embrittlement during exhumation, depending on the extent to which fluid–rock reactions proceeded. At one site, graphitic schists preserve textural evidence for two metamorphic reactions that modified XCO2XCO2 and/or fluid volume: (1) reaction between graphite and aqueous fluid that increased XCO2XCO2 without changing the molar amount of fluid, and (2) replacement of titanite by rutile, calcite, and quartz. The latter reaction involved net consumption of increasingly CO2-rich fluid. Areas where the first reaction proceeded are associated with abundant ...
Record Of Paleofluid Circulation In Faults Revealed By Hematite (U-Th)/He And Apatite Fission-Track Dating: An Example From Gower Peninsula Fault Fissures, Wales, Alexis K. Ault, Max Frenzel, Peter W. Reiners, Nigel H. Woodcock, Stuart N. Thomson
Fault rock low-temperature thermochronometry can inform the timing, temperature, and significance of hydrothermal fluid circulation in fault systems. We demonstrate this with combined hematite (U-Th)/He (He) dating, and sandstone apatite fission-track (AFT) and apatite and zircon (U-Th)/He (He) thermochronometry from fault-related fissures on the Gower Peninsula, Wales. Hematite He dates from 141 ± 5.1 Ma to 120 ± 5.0 Ma overlap with a 131 ± 20 Ma sandstone infill AFT date. Individual zircon He dates are 402–260 Ma, reflecting source material erosion, and imply a maximum Late Permian infill depositional age. Burial history reconstruction reveals modern exposures were ...
Phanerozoic Surface History Of The Slave Craton, 2017 Utah State University
Phanerozoic Surface History Of The Slave Craton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring
New apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85–90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the ...
Foreland-Directed Propagation Of High-Grade Tectonism In The Deep Roots Of A Paleoproterozoic Collisional Orogen, Sw Montana, Usa, Cailey B. Condit, Kevin H. Mahan, Alexis K. Ault, Rebecca M. Flowers
The study of deeply exhumed ancient collisional belts offers important constraints on geologic processes and properties complementary to inaccessible portions of the crustal column in active orogens. The ca. 1.8−1.7 Ga Big Sky orogeny in southwest Montana is a major convergent belt associated with the Proterozoic amalgamation of Laurentia. New structural, petrologic, and geochronologic data from the Northern Madison Range, crossing the NE-SW trend of the belt, record key information about the internal dynamics of the orogen. At least two phases of Big Sky−related deformation are preserved, both nearly coeval with peak metamorphic conditions of ∼0 ...
Hot Faults: Iridescent Slip Surfaces With Metallic Luster Document High-Temperature Ancient Seismicity In The Wasatch Fault Zone, Ut, Usa, James P. Evans, Mitchell R. Prante, Susanne U. Janecke, Alexis K. Ault, Dennis L. Newell
We document new geological indicators of ancient seismicity in the form of highly reflective, iridescent, hematite-coated fault surfaces. Small faults that cut the Paleoproterozoic Farmington Canyon Complex in the footwall damage zone of the Brigham City segment of the Wasatch fault (Utah, USA) are smooth to striated surfaces, tens of square centimeters to 30 m2 in area. The dull-rusty to high-metallic luster and moderate- to high-gloss surfaces exhibit multicolored elliptical iridescent patches ∼0.5–3 cm across. Preexisting hematite crystals were deformed during slip on 1–200-mm-thick slip surfaces. Textural observations, X-ray diffraction, X-ray photoelectron spectroscopy, electron backscattered diffraction analysis ...
Gravitational Study Of The Hastings Salt Dome And Associated Faults In Brazoria And Galveston Counties,Texas, 2017 Stephen F. Austin State University
Gravitational Study Of The Hastings Salt Dome And Associated Faults In Brazoria And Galveston Counties,Texas, Francis C. Okocha
Electronic Theses and Dissertations
Salt domes are important geological structures because they are potential major hydrocarbon traps and have a profound effect on overlying strata in the subsurface. Over five hundred salt domes have been located on the United States Gulf Coast region, including the Hastings Salt Dome. Hastings Oil Field is located about 40.2 km (25 miles) southeast of Houston, Texas. The Hasting oil field was discovered in 1934 and it was considered the largest oil reserve on the Gulf Coast. Its peak production of 75,000 BOPD (barrels of oil per day) was recorded in 1977 and it had a cumulative ...
Structural And Stratigraphic Reconstruction Of The Whiting Dome Salt Structure In Viosca Knoll-Mississippi Canyon, Gom, Using 3d Seismic Data, 2017 Stephen F Austin State University
Structural And Stratigraphic Reconstruction Of The Whiting Dome Salt Structure In Viosca Knoll-Mississippi Canyon, Gom, Using 3d Seismic Data, Matthew R. Worrell
Electronic Theses and Dissertations
Understanding the complexities of salt tectonics is one of the most important factors regarding seismic interpretation of stratigraphy, structure, and geomorphology in the Gulf of Mexico. Evaluating the processes affecting recent mobilization of salt in the shallow, well-imaged section can help provide analogues for older, similar occurrences in the deeper section, thereby providing structural models for the autochthonous salt and its effect on stratigraphy and even potential timing and migration issues of hydrocarbons.
Progradation of delta front and shelf to slope transitional sediments has expulsed and emplaced an allochthonous salt structure (Whiting Dome) in the Viosca Knoll and Mississippi Canyon ...
Spatio-Temporal History Of Fluid-Rock Interaction In The Hurricane Fault Zone, 2017 Utah State University
Spatio-Temporal History Of Fluid-Rock Interaction In The Hurricane Fault Zone, Jace Koger
All Graduate Theses and Dissertations
The Hurricane Fault is a 250-km long, west dipping, Basin and Range-bounding normal fault in SW Utah and NW Arizona that initiated in the mid-Miocene to Pliocene. It has been primarily active in the Quaternary, with slip rates of 0.2 – 0.6 mm/yr. There are multiple hot springs along its 250-km length and multiple late Tertiary-Quaternary basaltic centers broadly parallel the fault. Possible sources of hot spring fluids include deeply-circulated meteoric water that experienced water-rock exchange at high temperatures (>100 °C) and deep-seated crustal fluids. Aside from the source of modern hot spring fluids and heat, questions about ...
Insights On Magmatic Addition Beneath The Mid-Atlantic Coastal Plain From Crustal Seismic Refraction Data, 2017 University of New Mexico
Insights On Magmatic Addition Beneath The Mid-Atlantic Coastal Plain From Crustal Seismic Refraction Data, Thomas W. Luckie
Earth and Planetary Sciences ETDs
Magmatic addition can lead to intraplate crustal growth through plume-generated voluminous underplating of mafic material, particularly during early syn-rift processes. In addition, magmatism facilitates crustal growth and rift development by assisting extensional tectonic forces. Therefore, understanding the relationship between magmatism and rifting may help explain both these processes. In the summer of 2015 the GeoPRISMS Eastern North American Margin (ENAM) Community Seismic Experiment collected two margin-dip active source seismic refraction profiles in eastern North Carolina and southeastern Virginia using five onshore explosive shots on a northern profile and six on a southern profile (see figure). Analysis of these data resulted ...