Semester of Graduation
Spring
Degree
Master of Science (MS)
Department
Geology & Geophysics
Document Type
Thesis
Abstract
The Karoo Basin of South Africa is one of the largest African basins. It formed from the late Carboniferous (Pennsylvanian) to the Middle Jurassic and its sediments record 120 million years of depositional history, including Permian coals and shales of major economic significance for South Africa. Yet, although it is important to fully understand the Permian history of the Karoo Basin from an ecological, economical, and geological standpoint, the depositional setting is complex and still debated. Previous work on cross-basin correlation using palynological analyses have been performed and there is ongoing debate as to whether some deposits are lacustrine or marine in origin.
The main goals of this thesis project are to better constrain the past depositional environment of our sample locations, to correlate our sample site to sections of the Witbank and Highveld coalfields using palynostratigraphy, and to geochemically evaluate the borehole samples. The focus is on the glauconitic sandstones deposited on top of the major coal seams in the northern Karoo Basin. The material studied comes from 20 short (10 cm) borehole cores, drilled at five farm locations (Vaalbank 219, Vaalbank 238, Kruisementfontein 84, Rus En Verde 1647, and Erfenis 269). Palynological analysis of these cores reveals a diverse assemblage of well-preserved taeniate and non-taeniate pollen grains and fern spores with acritarch abundance increasing in the southern most sample locations.
Geochemical analyses were performed on 33 samples taken from the borehole cores. Measurements obtained include total organic carbon (TOC), stable carbon isotopic ratio, and carbon to nitrogen mass ratio (C/N). Ultimately, the integration of geochemical and palynological data allowed for the samples to be linked to the No. 4 coal seam of the Witbank and Highveld Coalfields and for the depositional setting to be identified as swamp to marine-deltaic in nature.
Recommended Citation
Moutevelis, Peter, "Revisiting the Depositional Setting of the Vryheid Formation in the Northern Karoo Basin, South Africa Using Palynological and Geochemical Analyses" (2021). LSU Master's Theses. 5274.
https://repository.lsu.edu/gradschool_theses/5274
Committee Chair
Warny, Sophie B.
DOI
10.31390/gradschool_theses.5274