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Piecing Together The Triassic/Jurassic Stratigraphy Along The South Flank Of The Uinta Mountains, Northeast Utah: A Stratigraphic Analysis Of The Bell Springs Member Of The Nugget Sandstone, Paul H. Jensen Jr.
Theses and Dissertations
Nomenclature for the Upper Triassic and Lower Jurassic strata along the south flank of the Uinta Mountains has been somewhat confusing because of the position of the study area between southern Wyoming, where one set of names is used, and central/southern Utah where a different set of formation names is used. The Nugget Sandstone or Glen Canyon Sandstone of the eastern Uinta Mountains overlies the Upper Triassic Popo Agie or Chinle Formation. The nature of the contact between these two formations is unclear both in stratigraphic location and conformability. The Chinle Formation consists, in ascending order, of the Gartra Member, …
A Comparative Analysis Of The Subsurface Stratigraphic Framework To The Geomorphic Evolution Of The Caillou Bay Headland, South-Central Louisiana, Elizabeth Mary Petro
A Comparative Analysis Of The Subsurface Stratigraphic Framework To The Geomorphic Evolution Of The Caillou Bay Headland, South-Central Louisiana, Elizabeth Mary Petro
University of New Orleans Theses and Dissertations
Studies have documented spatially and temporally variable rates of surface subsidence across the Mississippi River delta plain of Louisiana. Variations in patterns and rates of delta plain subsidence may reflect subsurface distribution of compactionprone lithosomes. This research investigates historical changes in the surface geomorphology of the Caillou Bay headland in relation to the distribution of subsurface lithosomes. The stratigraphic framework was developed for the headland, and lithosomes were identified to establish the distribution of different sedimentary units. The geomorphic evolution as indicated by maps was then evaluated in order to locate patterns of shoreline change and wetland loss for the …
Late Quaternary Louisiana Shelf-Margin Deltaic Deposition, North-Central Gulf Of Mexico, Casey Mobley
Late Quaternary Louisiana Shelf-Margin Deltaic Deposition, North-Central Gulf Of Mexico, Casey Mobley
University of New Orleans Theses and Dissertations
This study aims to establish a depositional framework for an area of the Louisiana shelf, north-central Gulf of Mexico. The depositional history of the study area is poorly understood, especially within the last cycle of major eustatic fluctuation (~18, 000 yrs BP – present). Data sets used in this study include pre-existing and previously unanalyzed two-dimensional, highresolution seismic profile records (Acadiana 86 and Acadiana 89), geotechnical foundation boring data (Coleman and Roberts, 1988a), and an industry lease block survey report (Cole, 1983). Seismic sequence stratigraphic methods are employed in this study to analyze seismic profile data. Seismic sequence analysis results …
Establising A High-Frequency Standard Reference Sequence Stratigraphy, Sea-Level Curve, And Biostratigraphy For Morrowan Strata Of The Lower Absaroka I Time Slice Based Upon The Bird Spring Formation, Arrow Canyon, Nevada, Kristen Phelps Briggs
Theses and Dissertations
For the same reasons which prompted its ratification in 1990 as the Global Stratotype Section and Point for the Mid-Carboniferous boundary, namely, section completeness, abundant fossils, and excellent exposure, the Morrowan Arrow Canyon Bird Spring strata is recommended as a candidate standard sequence stratigraphic reference for the Morrowan portion of the Lower Absaroka I supersequence. The stratigraphic architecture of Morrowan strata in Arrow Canyon was largely controlled by high-amplitude (100-m), high-frequency sea-level changes. Outcrop data and facies stacking patterns define 59 fifth-order fundamental cycles. These fundamental cycles stack into ten third-order sequences with an average duration of 320 ka. Changes …
Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer
Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer
Theses and Dissertations
Pliocene-Pleistocene sediments in the southeastern Acambay graben, central Mexico have yielded mammal fossils, including Equus simplicidens, cf. Rhynchotherium, ?Camelops, Mammuthus sp., Bison sp., and Antilocapra sp. The fossiliferous sediments include a period of lacustrine sedimentation in the late Pliocene-early Pleistocene that interrupted fluvial and alluvial sedimentation during the early Pliocene and Pleistocene. The sediments deposited in this late Pliocene paleolake record a history of lake level fluctuations, shown by lithologic variations in lacustrine sediments and abundance of vertebrate burrows. Volcanic and tectonic events in the Acambay graben were the major controls on sedimentation during Pliocene-Pleistocene time. …