Paleomagnetism of neoproterozoic intraplate igneous rocks in the southwest Kalahari craton, Namibia and South Africa

Abstract

Currently no reliable paleomagnetic pole for the Kalahari craton exists for the time period ~900-750 Ma, and it is the purpose of this thesis to acquire the first such pole. Here I report the results of paleomagnetic analyses from 47 sites from Neoproterozoic rocks within the Richtersveld Igneous Complex (~890 Ma), the older Bremen Complex (~890 Ma), and the Gannakouriep dike swarm (~795-790 Ma) within southern Namibia and adjacent parts of South Africa. The resulting grand mean pole obtained for the Kalahari craton lies at 73.9?N, 233.9?E (A95 = 4.5?). Comparison with published paleomagnetic poles from rock units of similar age from the Congo craton to the north supports a model in which the two cratons were originally separated by a wide ocean basin prior to the formation of the Gondwana supercontinent. However, additional work from the Congo craton is needed to test this hypothesis.