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- Keyword
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- Pegmatite (3)
- Barrier islands (2)
- Gulf of Mexico (2)
- Salt tectonics (2)
- Sediment transport (2)
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- Seismic attributes (2)
- Advection settling (1)
- Allosuture (1)
- Alteration (1)
- Barrier spit (1)
- Bayou Lafourche (1)
- Bell Creek granite (1)
- Caminada-Moreau Headland (1)
- Castlegate Sandstone (1)
- Coastal geomorphology (1)
- Coastal processes (1)
- Consolidation (1)
- Cordilleran foreland basin (1)
- Country Rock (1)
- Delft3d (1)
- Delta (1)
- Diapirism (1)
- Erongo (1)
- Estuarine channels (1)
- Ethiopian Plateau (1)
- Exhumation (1)
- Exomorphism (1)
- Facies classification (1)
- Faults, Geomorphology, Wetland Loss, Sediment Loading (1)
- Fine grained (1)
Articles 1 - 30 of 31
Full-Text Articles in Physical Sciences and Mathematics
Phosphate Mineralogy And Paragenesis Of The Fletcher Pegmatite, North Groton, New Hampshire, Susanna T. Kreinik
Phosphate Mineralogy And Paragenesis Of The Fletcher Pegmatite, North Groton, New Hampshire, Susanna T. Kreinik
University of New Orleans Theses and Dissertations
Investigation of phosphate assemblages selectively collected at the Fletcher Mine pegmatite, North Groton, New Hampshire, yielded eighteen discrete secondary phosphate species. Secondary phases were formed via metasomatic (high temperature) and hydrothermal (low temperature) alteration of primary triphylite and fluorapatite. Mineral associations bear proximal phases known to occur under contrasting conditions, both oxidizing and reducing, suggesting the formation of microenvironments during concomitant mineral generation. Late-stage hydrothermal fluids provide ions taken up in low temperature secondary phases with calcium and magnesium most prevalent in these suites. High iron to manganese ratios in analyzed specimens establish the relative evolution of the pegmatite host. …
Fine Grained Delta Front Sediment Transport, Sarah Noel
Fine Grained Delta Front Sediment Transport, Sarah Noel
University of New Orleans Theses and Dissertations
Insights into transformative coastal processes are unlocked though understanding sediment transport mechanisms in fine-grained delta front environments. Movement of fine-grained sediments on delta fronts is not wholly explained through advection settling models. While advection settling models generally assume deposition into a still body, numerical modeling of sediment re-entrainment suggests there may be tidal, wave, and/or non-steady hydrograph influences allowing particles to reach greater distances by altering the decelerating velocity field. This research explores both an advection settling model and a mass conservation Rouse profile model to understand the irreducible delta front processes controlling sediment deposition. Using field data collected on …
Machine Learning Model Selection For Predicting Global Bathymetry, Nicholas P. Moran
Machine Learning Model Selection For Predicting Global Bathymetry, Nicholas P. Moran
University of New Orleans Theses and Dissertations
This work is concerned with the viability of Machine Learning (ML) in training models for predicting global bathymetry, and whether there is a best fit model for predicting that bathymetry. The desired result is an investigation of the ability for ML to be used in future prediction models and to experiment with multiple trained models to determine an optimum selection. Ocean features were aggregated from a set of external studies and placed into two minute spatial grids representing the earth's oceans. A set of regression models, classification models, and a novel classification model were then fit to this data and …
Evolution And Stratigraphic Architecture Of Tidal Point Bars With And Without Fluvial Input: Influence Of Variable Flow Regimes On Sediment And Facies Distribution, And Lateral Accretion, Pricilla Souza
University of New Orleans Theses and Dissertations
Tide-influenced point bars represent a significant proportion of shallow-marine deposits, commonly developed along meandering channels in most backbarrier and estuarine systems. However, sedimentological studies to characterize this type of deposit are still emerging. They often present very heterogeneous internal architectures which development is controlled by the complex flow patterns operating in tidal environments. The study of the sedimentological and morphological characteristics of these features provides better understanding of the hydrodynamic processes that shape coastal systems and control their evolution as well as it contributes to better reservoir potential prediction and production strategy optimization, as tidal point bars may represent hydrocarbon …
Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock
Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock
University of New Orleans Theses and Dissertations
Light Detection and Ranging (Lidar) data are used to report the temporal and spatial patterns of subsidence as well as the potential contributors to subsidence within the Barataria and Terrebonne Bays. In recent decades, subsidence in southeast Louisiana has become a topic of substantial and growing concern to the scientific community, the local residents, and all those invested in the region. Lidar data were acquired from the United States Geological Survey (USGS) and the LSU Center for Geoinformatics. The data has been manipulated to map the differenced Lidar, complete an instantaneous slope analysis, and determine the thickness of the Holocene …
Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh
Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh
University of New Orleans Theses and Dissertations
An in-depth field study of the Delacroix Island producing field illustrates the evolution of the east-trending Delacroix Island Fault during the last 13 My. Well log correlations and 3-D seismic interpretation of 22 subsurface bio-stratigraphic horizons across the fault reveal variable stratigraphic thicknesses and displacement. Wells, with well log curve data as shallow as 31 m (100 ft) below the surface, were used to calculate interval thicknesses, expansion indices, sediment accumulation rates, burial history and magnitudes of displacement. Through these analyses, a correlation was found between the positioning of ancient Miocene depocenters over Delacroix Island and a period of increased …
Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford
Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford
University of New Orleans Theses and Dissertations
Extensive shell ridges frame the edges of marsh platforms in parts of the Biloxi Marsh of southeast Louisiana. The exact sources of the shells in these accumulations have not been clearly identified but the most likely source is a combination of shells from modern offshore and shells excavated from buried St. Bernard delta deposits. Larger or fetch-protected ridges remain stable through time, whereas ridges facing open water are more mobile, moving as much as 38 m inland from July 2017 to January 2018. Behind stable ridges, marsh platform biomass is relatively unaffected. When ridges are mobile, vegetation is smothered, leaving …
Coupled Barrier Island Shoreline And Shoreface Dynamics, Benjamin S. Beasley
Coupled Barrier Island Shoreline And Shoreface Dynamics, Benjamin S. Beasley
University of New Orleans Theses and Dissertations
In Louisiana, barrier islands are undergoing morphological change driven by high rates of relative sea-level rise and interior wetland loss. Previous works utilized historical region-scale bathymetry and shoreline change analyses to assess coastal evolution. However, more localized assessments considering the role of sediment transport processes in regional evolution are lacking. This is essential to predicting coastal change trajectories and allocating limited sand resources for nourishment. Using bathymetric and shoreline data, 100-m spaced shore-normal transects were created to track meter-scale elevation change for 1880s, 1930s, 1980s, 2006, and 2015. An automated framework was used to quantify and track parameters such as …
Hydrodynamic Controls On The Morphodynamic Evolution Of Subaqueous Landforms, Timothy L. Nelson
Hydrodynamic Controls On The Morphodynamic Evolution Of Subaqueous Landforms, Timothy L. Nelson
University of New Orleans Theses and Dissertations
The southern Chandeleur Islands are an ideal setting to study shoal evolution given their history of submergence and re-emergence. Here, numerical models shed light on the attendant processes contributing to shoal recovery/reemergence following a destructive storm event. Simulations of a synthetic winter storm along a cross-shore profile using Xbeach shows that convergence of wave-induced sediment transport associated with repeated passage of cold-fronts initiates aggradation, but does not lead to reemergence. A Delft3d model of the entire island chain shows that as these landforms aggrade alongshore processes driven by incident wave refraction on the shoal platform, backbarrier circulation and resulting transport …
Seismic Facies Classification Of An Intraslope Minibasin In The Keathley Canyon, Northern Gulf Of Mexico, Lamine Meroudj
Seismic Facies Classification Of An Intraslope Minibasin In The Keathley Canyon, Northern Gulf Of Mexico, Lamine Meroudj
University of New Orleans Theses and Dissertations
This work examines several volume attributes extracted from 3D seismic data with the goal of seismic facies classification and lithology prediction in intraslope minibasins. The study area is in the Keathley Canyon protraction (KC), within the middle slope of the Northern Gulf of Mexico (GOM). It lays within the tabular salt and minibasins province downdip of the main Pliocene and Pleistocene deltaic depocenters. Interaction between sedimentation and mobile salt substrate lead to the emergence of many stratigraphic patterns in the intraslope minibasins. Interest in subsalt formations left above salt formations poorly logged. Facies classification using Artificial Neural Network (ANN) was …
Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon
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 …
Evidence Of Fault Movement During The Holocene In Southern Louisiana: Integrating 3-D Seismic Data With Shallow High Resolution Seismic Data, Joseph P. Frank
Evidence Of Fault Movement During The Holocene In Southern Louisiana: Integrating 3-D Seismic Data With Shallow High Resolution Seismic Data, Joseph P. Frank
University of New Orleans Theses and Dissertations
The Baton Rouge fault system of Louisiana is a well-known recently active system consisting of en echelon, east trending, down-to-the-south normal faults across the northeast periphery of the Mississippi River delta plain. Two, industry-donated, 3-D seismic surveys across 860 km2 image deep-seated faults below Lake Borgne, along an east strike that parallels previously well mapped segments of the Baton Rouge system. Four major faults (> 6 km fault trace) are imaged within the seismic surveys across the Lake. The industry seismic data were not processed for reliable imaging at depths (m). To bridge the depth gap in seismic, high …
Paleohydrology And Paleoecology Of The Neogene Siwalik Rocks, Nepalese Himalaya Using Multi-Proxy Lipid Biomarker Isotopic Study, Prabhat Chandra Neupane
Paleohydrology And Paleoecology Of The Neogene Siwalik Rocks, Nepalese Himalaya Using Multi-Proxy Lipid Biomarker Isotopic Study, Prabhat Chandra Neupane
University of New Orleans Theses and Dissertations
This study deploys compound-specific multi-proxy isotopic study of lipid biomarkers to understand Neogene climatic and ecological variabilities in the Himalayan foreland. The investigation of compound-specific carbon and hydrogen isotopes along with glycerol dialkyl glycerol tetraether (GDGT) is the first of its kind for the Nepalese Siwalik. A total of 49 mudstone (and some paleosol) samples were collected from the paleomagnetically age-constrained Siwalik strata in the Surai Khola and Karnali River sections.
δ13C results suggest a domination of C3 trees between 12 and 8.5 Ma, and a stepwise expansion of C4 grasses starting gradually at 8.5 Ma …
An Investigation Into The Origin, Composition, And Commercial Significance Of A Sedimentary Subsalt Formation: Keathley Canyon, Gulf Of Mexico, David Aaron Brassieur
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 for …
High-Frequency Tectonic Sequences In The Campanian Castlegate Formation During A Transition From The Sevier To Laramide Orogeny, Utah, U.S.A., David B. Cross
High-Frequency Tectonic Sequences In The Campanian Castlegate Formation During A Transition From The Sevier To Laramide Orogeny, Utah, U.S.A., David B. Cross
University of New Orleans Theses and Dissertations
Though stratigraphic correlations are abundant in the Cordilleran basin-fill, they rarely include along-strike transects providing a spatio-temporal sense of deformation, sediment-supply and subsidence. A new, high-resolution, regional strike-correlation of the Castlegate Formation reveals progressive northward-growth of the San Rafael Swell during two embryonic episodes of Laramide-style deformation in central Utah. The intrabasinal deformation-events produced gentle lithospheric-folding punctuated by erosional-truncation of upwarped regions. The earliest episode occurred at 78 Ma in the southern San Rafael Swell likely causing soft-sediment deformation and stratal-tilting. Following this the alluvial-plain was leveled and rapid, extensive-progradation took place. A second episode, at 75 Ma, where deformation …
Barrier Spit Evolution And Primary Consolidation Of Backbarrier Facies: West Belle Pass Barrier, La, John N. Kramer Iii
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 …
Applying Modern Interpretation Techniques To Old Hydrocarbon Fields To Find New Reserves: A Case Study In The Onshore Gulf Of Mexico, U.S.A., Josiah D. Hulsey
Applying Modern Interpretation Techniques To Old Hydrocarbon Fields To Find New Reserves: A Case Study In The Onshore Gulf Of Mexico, U.S.A., Josiah D. Hulsey
University of New Orleans Theses and Dissertations
This study shows how the use of modern geological investigative techniques can reopen old, “drained” hydrocarbon fields. Specifically, it looks at the White Castle Field in South Louisiana. This field has pay sections ranging from late Oligocene to late Miocene. The late Oligocene package is underexplored and understudied and contains 3 primary reservoirs (Cib Haz (CH), MW, and MR). This study established the depositional history of these reservoirs. During most of the late Oligocene, the White Castle Salt Dome was located in a minibasin on the continental slope. The CH and MW deposited in this minibasin. The CH is an …
Submarine Channel Evolution Linked To Rising Salt Dome, Mississippi Canyon, Gulf Of Mexico, Rachel C. Carter
Submarine Channel Evolution Linked To Rising Salt Dome, Mississippi Canyon, Gulf Of Mexico, Rachel C. Carter
University of New Orleans Theses and Dissertations
By examining halokinetics and channel evolution in a deep-water system, we investigate how submarine channel morphology is affected by changing seascape linked to diapirism. The study area is located in Mississippi Canyon, Gulf of Mexico (GOM), situated directly off the continental slope in a prominent salt dome region. Interactions of salt domes with submarine channels in the GOM are poorly documented. Utilizing 3D seismic data and seismic geomorphology techniques, a long-lived Plio-Pleistocene submarine channel system has been investigated to develop a relationship between variable phases of salt movement and plan-form morphology of preserved channels.
We suggest that halokinetics acts as …
Petroleum Play Study Of The Keathley Canyon, Gulf Of Mexico, Jean Pierre Malbrough
Petroleum Play Study Of The Keathley Canyon, Gulf Of Mexico, Jean Pierre Malbrough
University of New Orleans Theses and Dissertations
Beneath Keathley Canyon (KC) off the Southern Coast of Louisiana and Texas, allochthonous salt bodies have attained thicknesses of over 7620 m (25000 feet), providing excellent seals and migration pathways for hydrocarbons produced by post-rift sedimentary deposition. This study analyzes a small portion of the KC area, utilizing Petrel Seismic software and well information from the KC102 (Tiber) well.
An intra-Miocene wedge, expressed beneath salt, may provide information about movement of allochthonous salt over Wilcox sands, sediment compaction, and hydrocarbon pathways. Progradational sedimentation is the driving force which leads to faulting in the early Miocene, allowing Jurassic salt to rise, …
Mineralogy And Geochemistry Of Late Archean And Paleoproterozoic Granites And Pegmatites In The Northern Penokean Terrane Of Marquette And Dickinson Counties, Michigan, Christopher M. Johnson, Christopher M. Van Daalen
Mineralogy And Geochemistry Of Late Archean And Paleoproterozoic Granites And Pegmatites In The Northern Penokean Terrane Of Marquette And Dickinson Counties, Michigan, Christopher M. Johnson, Christopher M. Van Daalen
University of New Orleans Theses and Dissertations
This thesis focuses on mineralogy, geochemistry, and origin of eight pegmatites and two spatially associated granites of Late Archean and Paleoproterozoic ages located in Marquette and Dickinson Counties, Michigan. Biotite geochemistry reveals that both granites and all pegmatites are peraluminous and have an orogenic signature. However, bulk composition reveals the Humboldt granite is a peraluminous A-type granite and the Bell Creek granite is a peraluminous mix between I-, S-, and A-type granites. The Republic Mine pegmatite appears to be geochemically similar to the Bell Creek granite and Grizzly pegmatite. The Crockley pegmatite is genetically related to the Humboldt granite. The …
The Garnet Line In Oxford County, Maine Pegmatites., Myles Mathew Felch, Myles M. Felch
The Garnet Line In Oxford County, Maine Pegmatites., Myles Mathew Felch, Myles M. Felch
University of New Orleans Theses and Dissertations
The garnet line is a planar fabric occuring within the intermediate and core zone in many of the Oxford County, Maine pegmatites. This study focuses primarily on the textural and chemical characteristics of the garnet line within the Mt. Mica and western Mt. Apatite quarries. Smaller, but similarly textured garnet line analogs from the Bennett, Emmons, Havey and Tamminen quarries are also investigated. All of these textures represent specific fractionation events within their respective dikes. In some of these locations, multiple stages of crystallization occur and appear to be post-magmatic, related to late stage metasomatism. These late stage fluids are …
Contact Zone Mineralogy And Geochemistry Of The Mt. Mica Pegmatite, Oxford County, Maine, Kimberly T. Clark
Contact Zone Mineralogy And Geochemistry Of The Mt. Mica Pegmatite, Oxford County, Maine, Kimberly T. Clark
University of New Orleans Theses and Dissertations
This study focuses on exocontact mineral assemblages to determine composition, thermal signatures, and the extent of exomorphism that occurred between the Mt. Mica pegmatite and the migmatite host rock at the contact. Biotite-garnet thermometry of country rock samples resulted in an average temperature estimate of 630 °C. Measured biotite Fe/(Fe+Mg) ratios were used to calculate an fO2 of -18. The results indicate that the country rock and pegmatite formed under similar oxidizing conditions near the quartz-fayalite-magnetite (QFM) equilibria buffer. Whole rock (REE) analysis indicates an interaction trend between the country rock and pegmatite. Exomorphism does not appear to have …
An Analysis Of The Green Knoll Salt Dome, Located In The Southeast Green Canyon, Deep Water Gulf Of Mexico, Randal J. Broussard
An Analysis Of The Green Knoll Salt Dome, Located In The Southeast Green Canyon, Deep Water Gulf Of Mexico, Randal J. Broussard
University of New Orleans Theses and Dissertations
The western portion of the Mississippi/Atwater fold belt in the Gulf of Mexico contains what is known as The Green Knoll Salt Dome. The creation and growth of this salt diapir is punctuated by salt deposition, salt migration, sediment loading, and is linked to the “Frampton” fold belt. An indicator of these growth periods is exhibited in an angular unconformity (halo-kinetic sequence boundary) that flanks the diapir. This unconformity developed during the Miocene-Pliocene chronostratigraphic boundary. The “Redwood” (Green Canyon 1001) prospect was drilled after the discovery of middle Miocene sands containing hydrocarbons in the Mad Dog field (GC 826). The …
Mineralogy And Geochemistry Of The Erongo Granite And Interior Quartz-Tourmaline Orbicules And Nyf-Type Miarolitic Pegmatites, Namibia, Andrew P. Boudreaux
Mineralogy And Geochemistry Of The Erongo Granite And Interior Quartz-Tourmaline Orbicules And Nyf-Type Miarolitic Pegmatites, Namibia, Andrew P. Boudreaux
University of New Orleans Theses and Dissertations
The early Cretaceous anorogenic Erongo Granite of Namibia is known to host abundant boron mineralization in rounded, quartz-tourmaline clusters and in NYF-type miarolitic, pegmatitic cavities. Rock and mineral samples were taken from the bulk granite, tourmaline nests, and miarolitic cavities and analyzed using a variety of modern analytical techniques. Geochemical and mineralogical data suggest substantial input from the metasedimentary rocks of the Damara orogen was important in the genesis of the Erongo Granite magma. The geochemical signature of the Damara orogen is most evident in the tourmaline clusters and miarolitic cavities, where fractional crystallization accumulated volatile and incompatible elements enough …
Geochemistry, Mineralogy And Evolution Of Mica And Feldspar From Within The Mount Mica Pegmatite, Maine, Usa, Karen L. Marchal
Geochemistry, Mineralogy And Evolution Of Mica And Feldspar From Within The Mount Mica Pegmatite, Maine, Usa, Karen L. Marchal
University of New Orleans Theses and Dissertations
Mount Mica is a poorly zoned sodic LCT-type pegmatite consisting dominantly of quartz, albite and muscovite in the outer portions. Potassium feldspar and lepidolite are restricted to the core zone. Micas in the wall zone are chemically homogeneous, but abruptly evolve into higher Cs + Rb bearing lithian muscovites and lepidolites in the core zone. The abrupt increase of the Cs, Rb in K-feldspar, and Cs, Rb and F in muscovite, and lepidolite combined with the occurrence of highly evolved species lepidolite, pollucite, elbaite, beryl and spodumene in the core zone suggests that incompatible elements were retained in residual …
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
University of New Orleans Theses and Dissertations
Accumulations of brackish groundwater exist across south Louisiana within the shallow, south-dipping Pleistocene to Upper Miocene Baton Rouge Aquifer System (BRAS). This research investigates the source of brackish groundwater through geochemical analysis of representative groundwater samples by comparing the following geochemical ratios along with other trace elements. Low Bromide (Br)/Chloride (Cl) and Potassium (K) /Cl ratios, high Sodium (Na) /Cl ratios, trace Magnesium (Mg) concentrations, and low Strontium (Sr) 87/Sr86 in brackish waters from the BRAS are inconsistent with in situ saline water from marine formation fluids of similar age. The ratios are consistent with in situ saline-water …
Geomorphologic Evolution Of A Rapidly Deteriorating Barrier Island System With Multiple Sediment Sources: Eastern Isles Dernieres, Louisiana, 1887 To 2006, Benjamin T. Kirkland
Geomorphologic Evolution Of A Rapidly Deteriorating Barrier Island System With Multiple Sediment Sources: Eastern Isles Dernieres, Louisiana, 1887 To 2006, Benjamin T. Kirkland
University of New Orleans Theses and Dissertations
Trinity, East, and Wine Islands make up the eastern half of the Isles Dernieres barrier arc in south-central Louisiana. Formed following the abandonment of the Lafourche delta complex, subsidence and storm erosion have led to rapid deterioration of the system. Since 1887, the land area of the islands has decreased seventy-seven percent, and the gulf shoreline has retreated landward more than a kilometer. Wave ravinement on the shoreface of the islands is responsible for the most sediment loss; liberated sediment travels longshore to tidal inlets. The dominant ebb tidal currents then transport the sediment to where it is deposited in …
Transitional Facies And Sequence Stratigraphic Complexity Of Shallow-Marine Star Point Formation To Coastal-Plain Blackhawk Formation Along Depositional-Strike, Wasatch Plateau, Utah, Andrew M. Ranson
University of New Orleans Theses and Dissertations
Facies and stratigraphic architecture right at the transition from marine to non-marine environments is poorly documented. In the Cretaceous outcrops of Utah, Star Point and Blackhawk Formations are well studied. The nature of spatio-temporal transition of these two Formations, in the deposition-strike orientation, remains undocumented. This study characterizes facies and stratigraphic complexity at the transition of the two Formations that crop out in depositional-strike orientation in the Wasatch Plateau. Data from outcrop including photomosiacs and measured sections demonstrate this complexity at a range of scales. The Star Point constitutes a shoreface environment. The Blackhawk constitutes a coastal-fluvial environment.
In the …
Mineralogy And Geochemistry Of Anorogenic Granitic Miarolitic Pegmatites Associated With The White Mountain Intrusive Suite, New Hampshire, Kristen F. Camp
Mineralogy And Geochemistry Of Anorogenic Granitic Miarolitic Pegmatites Associated With The White Mountain Intrusive Suite, New Hampshire, Kristen F. Camp
University of New Orleans Theses and Dissertations
Subvolcanically emplaced granitic, miarolitic pegmatites associated with the White Mountain Igneous Province (WMIP), New Hampshire, were sampled and analyzed using modern analytical techniques including X-ray fluorescence, electron microprobe, scanning electron microscopy, and direct-coupled plasma spectrophotometry. Analytical results suggest that all the sampled miarolitic pegmatites from this study are petrogenetically related to the same intrusive suite, the WMIP. Based on the geochemical data, all the samples formed in an anorogenic tectonic setting and are rift-related. They are classified as NYF-type and plot in the “within plate granite” field on tectonic discrimination diagrams. The majority of the samples are peraluminous, A1 …
Understanding Uplift Of The Ethiopian Plateau From Longitudinal Profile Analysis Of The Blue Nile Drainage System, Prabhat Chandra Neupane
Understanding Uplift Of The Ethiopian Plateau From Longitudinal Profile Analysis Of The Blue Nile Drainage System, Prabhat Chandra Neupane
University of New Orleans Theses and Dissertations
The Ethiopian Plateau is one of the few tectonically-active regions on Earth that is situated in continental rift zones. About 1.6 km deep gorge of the Nile was carved by the Blue Nile River on the Ethiopian Plateau, as the plateau has been experiencing continuous uplift and exhumation in the Cenozoic. Here, we used quantitative analysis of longitudinal rive-profile forms and parameters (knickpoint and normalized steepness-index ksn) of the Blue Nile tributaries to tease out regional tectonic signals.
244 knickpoints were examined in the tributaries, majority (>80%) of which are unassociated with lithology or geological structures. Knickpoint …