S U M M A R YWe report palaeomagnetic and 40 Ar/ 39 Ar age data for dykes that intrude the ∼2 Ga eastern Bushveld Igneous Complex (BIC). The dykes were previously assumed to be of Karroo age (Jurassic ∼ 180 Ma) based on their NE-SW orientation. Palaeomagnetic data (pole position 8.7 • N, 22 • E; dp/dm = 18/20.6 • ), however, clearly demonstrate that these dykes are Precambrian in age, either ∼1.9 Ga and close to the Early Proterozoic Bushveld age, or 1649 ± 10 Ma based on 40 Ar/ 39 Ar plagioclase laser fusion ages from one of the dykes. Both normal and reverse polarity dykes are identified, and a positive reversal test together with a semi-conclusive contact test attests to a primary magnetization. If the 40 Ar/ 39 Ar age represents a primary cooling age then palaeomagnetic poles from South Africa (Kalahari) at ∼1.9 to ∼2 Ga and ∼1650 Ma are virtually identical, and suggest an apparent polar wander loop; alternatively, the Kalahari Craton drifted from high southerly (>50 • ) to high northerly latitudes (or vice versa) during this interval. Conversely, if we assign a ∼1.9 Ga age for dyke emplacement as suggested from a comparison with Kalahari palaeomagnetic poles (e.g. Waterberg-Soutpansberg pole), the ∼1650 Ma 40 Ar/ 39 Ar age must relate to a thermal disturbance that did not erase the primary magnetic signature.
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