Discovery of itacolumites in the central highlands of Madagascar

Abstract

The presence of itacolumites, or flexible quartzites, and the precise geological descriptions of the same have hitherto been reported only in India, Brazil, and the Appalachian region of the USA. In this paper, we report the discovery of itacolumites from three localities in the central highlands of Madagascar. The localities are underlain by the Mesoproterozoic Itremo Group. The occurrence and petrography of these itacolumites and the results of SEM observations are summarized in this paper. The itacolumites from Madagascar contain very coarse grained one beside the fine-to-medium-grained varieties that are common to India, Brazil, and the Appalachians. Furthermore, the itacolumites of Madagascar occur over a wide area of exposure, supporting the opinion that their formation was a result of chemical weathering.