High-resolution heavy mineral stratigraphy of selected Precambrian successions underlying the Nama Group in Namibia
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This project research the provenance of Precambrian formations: Kuibis Formation, Holgat Formation, Numees Formation, Blaubeker Formation, Matchless Amphibolite, Aubures Formation, and Klein Aub Formation from Namibia. The aim is to enhance provenance understanding, as detrital zircons from previously studies on the Ediacaran rocks show zircon ages older than 1.0 Ga; with a basis in high-resolution heavy mineral studies using different techniques; Scanning Electron Microscope, X-Ray Diffraction (XRD), uranium-lead zircon dating (U-Pb), Mineral Liberation Analyzer (MLA), and Electron Microprobe (EMPA). Results show that the Klein Aub Formation is dominated by magnetite, mica, quartz, and titanites. The Aubures Formation is dominated by magnetite, ulvospinel, and quartz. The Blaubeker Formation is dominated by quartz, magnetite, carbonates and chamosite. Quartz, mica, rutile, and magnetite dominate the Numees Formation. Quartz, carbonates, and rutile dominate the Holgat Formation. The Kuibis Formation is dominated by quartz, rutile, and apatite. The EMPA results for tourmalines and garnets were plotted in ternary diagrams to evaluate potential source areas, in combination with XRD results that showed evidence of minerals associated with the Pilanesberg Complex in NW South Africa, Northern Kalahari Manganese Field, Irumide belt in Zambia, and Limpopo belt. Moreover, terminal velocity was calculated from the MLA results. The Matchless Amphibolite show evidence from amphiboles, pyroxenes, and garnets of a Fe-Mn-Ca-Al-rich protolith. This work show the importance of microprobe analysis in combination with MLA, among using other methodologies when U-Pb analysis is insufficient. Lastly, the methodology is relevant in all stages of the hydrocarbon industry; exploration to production; analyzing reservoir characteristics; understanding and predicting reservoir distribution and quality; and geosteering.
Master's thesis in Petroleum Geosciences engineering