Palaeocene Coralline Algal Growth forms and their Significance in the Cauvery Basin, South India

In the present work, we bring out the palaeoenvironmental significance of the growth-form morphology of coralline algae present in the Ninniyur Formation (Palaeocene) of the Cauvery Basin, South India. Our observations indicate presence of four types of coralline algal growth forms in the studied sections of the Ninniyur Formation: laminar, branching, columnar and massive and fragmented. They seem to have been controlled by depositional environments, each characterising a distinctive set of conditions pertaining to water-energy and depth. It appears that the carbonate environment, in which the Ninniyur Formation was deposited, was well differentiated into subenvironments due to changing environmental constraints (depth of deposition and hydraulic energy). The biota responded to these factors through habitat partitioning which possibly hastened the process of evolution of varied types of coralline algal associations and growth morphology leading to distinctive biofacies characters.