Rock building Cretaceous - Tertiary algae from India - an ecological perspective

Abstract

Fossil benthonic photosynthetic algae capable of calcification contributed to the formation of Indian Cretaceous-Tertiary carbonate deposits. A comparative assessment of different marine calcareous algal assemblages known from various sedimentary basins and their ecological requirements have been highlighted. A comprehensive synthesis and retrospect of research on calcareous algae demonstrate extensive growth of green and red algae during Cretaceous-Tertiary times in India. The calcareous blue-green algae are feebly represented in the Cretaceous deposits and not recorded from the Tertiary deposits. Various ecological factors determined the distribution of different calcareous algal groups. An apparent extinction of calcareous algae is attributed to gaps in our knowledge and evolutionary changes.