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Detrital Tourmaline As An Indicator Of Provenance: A Chemical And Sedimentological Study Of Modern Sands From The Black Hills, South Dakota, David Brent Viator Jan 2003

Detrital Tourmaline As An Indicator Of Provenance: A Chemical And Sedimentological Study Of Modern Sands From The Black Hills, South Dakota, David Brent Viator

LSU Master's Theses

Detrital tourmaline has proven useful as a provenance indicator mineral of ancient sedimentary/metasedimentary units due to its presence in many rock types, chemical responsiveness to environments of formation, complex and variable chemical compositions, high resistance to chemical and mechanical weathering, and stability through diagenesis and metamorphism. This study further establishes detrital tourmaline as a provenance indicator mineral by examining the chemical and sedimentological relationships between modern detrital tourmalines in the sediments of the Black Hills, South Dakota, USA, and in situ tourmalines from southern Black Hills’ tourmaline-bearing metasedimentary rocks, granites, and rare-element enriched pegmatites. Results show that detrital tourmaline is …


Middle Miocene Grounding Events On The Ross Sea Outer Continental Shelf, Antarctica, Juan Manuel Chow Jan 2003

Middle Miocene Grounding Events On The Ross Sea Outer Continental Shelf, Antarctica, Juan Manuel Chow

LSU Master's Theses

The middle Miocene δ18O enrichments from deep-sea data and eustatic sea level falls are traditionally attributed to expansion of the East Antarctic Ice Sheet. Interpretations of such data have led many to conclude that the West Antarctic Ice Sheet (WAIS) was not well-developed until the late Miocene. In such a scenario, middle Miocene glaciation on the Ross Sea shelf would have had to be minimal, perhaps in the form of ice caps, to be consistent with proxy data. New seismic-stratigraphic analysis of the Ross Sea outer continental shelf suggests that at least five grounding events (ice sheet advances …


An Investigation Of A Salt-Dome Environment At South Timbalier 54, Gulf Of Mexico, Robert E. Little, Jr Jan 2003

An Investigation Of A Salt-Dome Environment At South Timbalier 54, Gulf Of Mexico, Robert E. Little, Jr

LSU Master's Theses

Salt domes have been studied in the Gulf Coast region to look at how, why, and where saline waters are located within these field areas. Fluid flow model and pathway studies can be helpful to the research of saline water migration because it can be correlated to hydrocarbon migration in petroleum exploration. The South Timbalier 54 field occurs over a salt dome that sits at approximately 3,048 meters beneath the seafloor. Two major faults were found originating from the salt dome up into the shallow section of the field. The sands were deposited in fluvial, deltaic, or marine environments. The …


Correlation Of Core Characteristics To Outcrop Upper Jackfork Group Turbidites, Degray Lake, Arkansas, Daniel James Golob Jan 2003

Correlation Of Core Characteristics To Outcrop Upper Jackfork Group Turbidites, Degray Lake, Arkansas, Daniel James Golob

LSU Master's Theses

Pennsylvanian age Jackfork Group cores from the DeGray Lake Dam and outcrop from the east wall of the DeGray Lake Spillway, Arkansas, provide an opportunity for a detailed study on the transport and depositional characteristics of a fine-grained, deep-water depositional system. Two phases of resedimentation processes are responsible for deposition of the sediments in the cores and the outcrop. Primary resedimentation processes transport terrigenous sediments from the shelf or basin edge into the middle fan environment, while secondary resedimentation alter the sediments after they are initially deposited in the environment. Debris flows, slurry flows, and high and low density turbidity …


Compositional Systematics Of Deep, Low Salinity Formation Waters In The Upper Wilcox Of Southeastern Texas, Kathleen (Kt) Moran Jan 2003

Compositional Systematics Of Deep, Low Salinity Formation Waters In The Upper Wilcox Of Southeastern Texas, Kathleen (Kt) Moran

LSU Master's Theses

Overpressured Eocene Wilcox sandstones in the Newton County, Texas Sabine Tram field contain water with salinities ranging from 14 to 28 g/L. The solutes appear to fall loosely into three groups. Na, Ca, and Mg follow systematics previously known globally for saline formation waters whereby their concentrations are controlled by fluid-mineral equilibrium. Cl, Br, I, and B are conservatively diluted constituents of some saline endmember that is not solely connate marine. Potassium does not follow any known basinal systematic, and the formation water is supersaturated with respect to SiO2 by an order of magnitude. Meteoric water is not a probable …


Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink Jan 2002

Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink

LSU Master's Theses

The Upper Cretaceous-Paleocene El Molino Formation of the Bolivian Central Andes consists of mixed siliciclastic and carbonate strata alternately interpreted as syn-rift, post-rift thermal sag and foreland basin deposits. These deposits can be divided into two lithostratigraphic sequences. The first sequence consists of a carbonate, carbonate sand and mudrock lower member, a middle member consisting entirely of mudrock and an upper member containing carbonates and mudrocks. The second lithostratigraphic sequence contains a lower member composed of carbonate sands, carbonates and mudrocks, and an upper member consisting of a coarsening upwards sequence of sandstones and mudrocks. Within these lithostratigraphic sequences, five …


Significance Of Variations Among Ancient Deltaic Deposits In The Arkoma Basin, North-Central Arkansas, Christine Michelle Wright Jan 2002

Significance Of Variations Among Ancient Deltaic Deposits In The Arkoma Basin, North-Central Arkansas, Christine Michelle Wright

LSU Master's Theses

The Arkoma Basin is one of several foreland basins formed in association with the Ouachita orogeny. The Arkoma Basin has been studied in depth with regard to stratigraphy, depositional environments, structure and its relationship to the Appalachian-Ouachita orogenic event. This study focuses on the variability of the deltaic deposits within the Arkoma Basin and the significance of the variables to both the delta complex and the overall tectonic setting. The specific characteristics to be investigated include variations in paleocurrent directions, bed thicknesses, bed geometries, organic contents, sand/shale ratios, mineral assemblages and fossil assemblages. In the case of the Arkoma deltaic …


Characterization Of The Lower Atoka Formation, Arkoma Basin, Central Arkansas, Kelly R. Lagrange Jan 2002

Characterization Of The Lower Atoka Formation, Arkoma Basin, Central Arkansas, Kelly R. Lagrange

LSU Master's Theses

The Carboniferous Lower Atoka outcrops in the Arkoma Basin of Central Arkansas contain turbidite deposits in a channelized and unchannelized submarine fan setting. The objectives of the study were to determine depositional characteristics and reservoir performance of these fine-grained submarine fan deposits. Four outcrops (Highway 5, Perryville, Chula, and Danville) were studied and described in detail emphasizing sedimentary facies, vertical succession of beds, sedimentary structures, and other small-scaled features that cannot be resolved in subsurface deposits. Five distinct sedimentary facies were recognized: Facies A - massive sandstones, Facies B - thin-bedded sandstones with a mudstone drape, Facies C - interbedded …


Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton Jan 2002

Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton

LSU Master's Theses

Tertiary age rocks are exposed along north-south trending structures throughout the hinterland Altiplano plateau, central Andes. The east limb of the Corque syncline (SW Bolivia) contains the thickest and most continuous successions of late Eocene–Oligocene age non-marine strata (Potoco Formation) on the Altiplano. The Potoco is up to ~6500 m thick and has continuous exposure >103 km2 making it the thickest and most extensive remnant of the mid-Tertiary Altiplano basin. Basin fill during late Eocene–Oligocene time remains the most rapid and sustained period of deposition since Andean orogenesis, recording a long-term sediment accumulation rate of ~0.5 mm/my. The …


Overpressuring, Diagenesis, And Fluid Flow At The Matagorda Island 519 Field, Offshore Texas, Gulf Of Mexico, Kera Gautreau Spears Jan 2002

Overpressuring, Diagenesis, And Fluid Flow At The Matagorda Island 519 Field, Offshore Texas, Gulf Of Mexico, Kera Gautreau Spears

LSU Master's Theses

The relations between overpressuring, diagenesis, and fluid flow in sedimentary basins are complex and multifaceted. The Matagorda Island 519 field (MI 519), offshore Texas, provides an excellent area for investigating some of these relations. The top of overpressure at MI 519 occurs at a depth of 3.5 to 3.8 km in a Lower Miocene deltaic sequence. On the basis of log-derived lithostratigraphy, the pressure seal does not appear to be lithologic in origin. Geochemical, mineralogical, and cuttings information indicate instead that the precipitation of diagenetic calcite and possibly quartz cements has been the major factor in seal development. Stratigraphic variation …


Distributary Mouth Bar Formation And Channel Bifurcation In The Wax Lake Delta, Atchafalaya Bay, Louisiana, Anton J. Dumars Jan 2002

Distributary Mouth Bar Formation And Channel Bifurcation In The Wax Lake Delta, Atchafalaya Bay, Louisiana, Anton J. Dumars

LSU Master's Theses

The Mississippi River has undergone at least seven cyclic avulsions during the Holocene epoch. The latest avulsion, down the Atchafalaya River into the Gulf of Mexico, has produced two bayhead deltas prograding into Atchafalaya Bay. The Wax Lake Delta, typical of other Mississippi sub-deltas, has a natural anastomosing channel pattern. In contrast, the Atchafalaya Delta, situated in the eastern side of the Bay, has experienced sporadic and limited growth due to the dredging of a navigation channel below natural depth. Channel bifurcation, and sediment transport processes and responses, were investigated in the Wax Lake Delta, using channel flow velocities, suspended …