Stratigraphy and Sedimentology of a Late Neoproterozoic Shelf-Slope System, Flinders Ranges, South Australia: an Excellent Outcrop Analogue for Marginal Marine to Deepwater Transitions in the Subsurface
Australian School of Petroleum, University of Adelaide, Adelaide, South Australia, Australia
This PhD project will consist of both field and laboratory studies of sedimentary rocks in the Ediacaran Billy Springs Formation and the Pound Subgroup, a series of potentially time-equivalent strata in South Australia that form a transition from coarser deltaic sands in the south, to offshore mudstones in the north. Several field trips will be undertaken to measure and describe the stratigraphy and sedimentology of these formations, and rock samples will be collected and analysed using traditional petrographic methods, scanning electron microscopy, and QEMSCAN imaging. Detrital zircon grains will be extracted from samples, and will be used to constrain the maximum age of deposition and infer sediment sources and source directions using previously established ages of surrounding craton blocks. Data will be used to reconstruct the paleogeographic and paleoenvironmental conditions at the time of deposition. The studied interval will be compared to analogous settings around the world, both modern and ancient, in order to aid in the overall understanding of slope and shelf-type environments in the geologic record, including the subsurface. The final part of this study will examine conglomerates in the otherwise sand-dominated Pound Subgroup, which are found directly adjacent to the Mt. Frome diapir. It is likely that the diapir was emergent during Pound time, resulting in the shedding of coarser material uplifted from deeper in the basin. Such studies of syndepositional diapir effects are rare, and this study would be a key data point in improving our understanding these important sedimentary systems.
AAPG Search and Discovery Article #90199 © 2014 AAPG Foundation 2014 Grants-in-Aid Projects