Abstract
M.Sc. (Geology)
The Koras Group forms an intricate part of the Namaqua-Natal Metamorphic Province within southern Africa. This well preserved Mesoproterozoic volcano-sedimentary succession provides the basis of this study. The aim of this dissertation is to investigate and identify the position of the Kalahari Craton in relation to Laurentia and the greater Rodinia supercontinent. Paleomagnetic and detrital zircon provenance results are presented which are used to demonstrate the proposed position of the Kalahari Craton within Rodinia.
During the study, samples for paleomagnetic analysis were collected from both the sedimentary and volcanic units of the upper and lower successions of the Koras Group. Field stability tests were conducted in order to better constrain the reliability of these poles by indicating the primary magnetization. Two poles were established: a pole located at 47.8°N, 58.0°E and an A95°of 9.3° and constrained with an age of 1157±44Ma (Pettersson et al. 2007) was obtained for the lower succession, and a paleomagnetic pole located at 49.5°N, 11.9°E and an A95° of 8.2° with an age constraint of ~1090Ma was obtained for the upper succession. Both these poles were used to further develop the apparent polar wander path (APWP) for the Mesoproterozoic Kalahari Craton. The pole calculated from samples belonging to the Bossienek Formation fits between the Premier Mine Kimberlite pole and the Umkondo paleomagnetic pole. The slightly younger pole calculated from samples from the upper succession fits between the Aubures Formation pole and the Namaqua Metamorphics pole (further away).
With regards to the provenance, three sedimentary units were sampled throughout the whole Koras Group. Detrital zircon analysis was completed using both quadrupole and multi collector laser ablation inductively coupled plasma mass spectrometry. Slight differences between the detrital zircon age populations between the lower and upper succession are...