Physical Sciences and Mathematics Commons^™

The Pennsylvanian–Permian Transition In The Low-Latitude Carbonate Record And The Onset Of Major Gondwanan Glaciation, Jesse Koch, Tracy D. Frank

Department of Earth and Atmospheric Sciences: Faculty Publications

Recent studies suggest a marked expansion of glacial ice across much of Gondwana beginning in the earliest Permian. Because expansion of glacial ice results in a lowering of sea level, the imprint of ice expansion should be evident worldwide as significant exposure event, hiatuses, or other evidence for sea level drop at or near the Pennsylvanian–Permian boundary. This literature review investigates the signature of an Early Permian expansion of Gondwanan ice through examination of stratigraphic records from eight carbonate-dominated, palaeotropical regions across Pangaea. Tropical carbonate environments are used because most form in tectonically quiescent regions and are sensitive indicators of …

Sedimentology And Stratigraphy Of The Upper Pennsylvanian – Lower Permian Systems Of Western Nebraska, Usa, Chesney L. Gilleland

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Depositional patterns and regional stratigraphic relationships in the carbonate-dominated Pennsylvanian and Permian deposits in western Nebraska are not well established due to poor surface exposure. Examination of petroleum drillcores and wireline logs, along with thin sections and biostratigraphic analysis allow new insight into facies distributions, depositional environment, and regional stratigraphic relationships. Nine shallowing upward cycles are identified that can be correlated across the southern Nebraska Panhandle within the Pennsylvanian (Virgilian)-Permian (Wolfcampian) stratigraphy (Admire, Council Grove, and Chase Groups). These cycles are composed of facies representing deposition from open marine through nonmarine environments. Results show that depositional settings in western Nebraska …

Comparing Middle Permian And Early Triassic Environments: Mud Aggregates As A Proxy For Climate Change In The Karoo Basin, South Africa, Bryce Pludow

Honors Theses

The Permian-Triassic Boundary (252.6 Ma) is an interval under intense study as changes across it represent the greatest loss of life in Earth history. Although the event is well understood and constrained in the marine realm, questions remain about extinction, climate, and environmental conditions on land. The Karoo Basin of South Africa is a focus of study due to the complete nature of its terrestrial record, specifically across this boundary.

The identification of pedogenic mud aggregates document the presence of soils with abundant clays produced in a seasonally arid environment. The occurrence of these aggregates in low-sinuosity Early Triassic fluvial …