Paleomagnetism of the lower two unconformity-bounded sequences of the Waterberg Group, South Africa: Towards a better-defined apparent polar wander path for the Paleoproterozoic Kaapvaal Craton
نویسندگان
چکیده
Paleomagnetic data from more than 250 samples of the lower part of the Waterberg Group (Nylstroom Subgroup) are reported in order to reevaluate the apparent polar wander path (APWP) of the Kaapvaal craton during the Paleoproterozoic Era. Our study broadly confirms the established APWP, but reveals some previously unidentified complexities in the time interval ~2.05 Ga to ~1.87 Ga. A primary remanence direction from the lower part of the Swaershoek Formation provides a paleomagnetic pole of (36.5° north, 051.3° east, K = 23.4, A95 = 10.9) for the Waterberg unconformity-bounded sequence I (WUBS-I) at ~2.05 Ga. A large shift in pole position takes place from the lower Swaershoek into the upper Swaershoek Formation and overlying Alma Formation of Waterberg unconformity-bounded sequence II (WUBS-II; pole at -10.5° north, 330.4° east, K = 25.0, A95 = 9.8), confirming the existence of a major unconformity and/or rapid continental motion within the span of Swaershoek deposition.
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