Letter | Published:

A failed Gondwana spreading axis in southern Africa


AN outstanding geological feature revealed by the recently published Reconnaissance Aeromagnetic Survey of Botswana1 is a well defined swarm of closely spaced dykes crossing the northern part of the country on a strike of approximately N 110°E (Fig. 1). We present here an interpretation of this newly discovered dyke swarm in terms of a failed Gondwana spreading axis.

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