Benthic Foraminiferal Distribution from Mahabalipuram - Marakkanam Offshore, East Coast of India

Tabita Symphonia, D. Senthil Nathan

Abstract: The present study aims to understand the distribution of benthic foraminifera in the surface sediments collected from the offshore region between Mahabalipuram and Marakkanam along the east coast of India. Analysis reveals the presence of 89 species belonging to 16 families and 5 orders. Faunal assemblage in the fine grained sediments are characterised by Cibicides spp. and Ammonia spp. predominantly whereas the sandy substrate is dominated by amphisteginids. Quinqueloculina spp. is the most frequently occurring species with continuous distribution. Although Amphistegina spp. are the abundant benthic group, they exhibit uneven distribution. Relict foraminifera are present in relatively higher abundance at 35, 46 and 86 m depth. Thus, the benthic foraminiferal assemblage in this region explicitly portrays the influence of the nature of substrate along with changes in related environmental parameters.

Keywords: Benthic foraminifera, distribution, east coast, India