Narmada-Son Lineament of India Traced into Madagascar

An extension of the Narmada-Son lineament of peninsular India can be traced across northern Madagascar, the lineament having been continuous in Gondwanaland. The Indian section, now a narrow seismicrift, appears to be a deep fault. It influenced Precambrian and Phanerozoic sedimentation and is the locus for post-Deccan Trap carbonatite and fluorite occurrences. The Malagasy section shows comparable unusual rocks. Postulated sinistral movement along the Indian section of about 450 km culminating at 750 Ma BP was associated with volcanism, plutonism and base metal mineralisation. The structure may not then have been in existence in Madagascar.