Occurrence of Holocene Mammalian Remains and Mollusc Shells from Indian Sundarbans with Environment of Deposition

Abstract

Mammalian remains of Bubalus bubalis, Rucervus duvauceli of swampy forest environment and mollusc shells of mangrove and distinct fresh water ecosystem recovered from the C dated Peat, Silty Clay and Alluvial layers exposed at depth from 560 cm up to surface at Kumirmari and Dakshin Harishpur, south-east of Kolkata, West Bengal of Indian Sundarbans area were studied for animal remains assemblage zonations and analysis of palaeoenvironment during Holocene. Two Local animal remains assemblage zones were proposed for each section studied viz. KUI: Kumirmari and DHI: Dakshin Harishpur. Correlation of local zones of C dated sediments has revealed two RAZ: Regional Animal remains Assemblage Zones viz. RAZ-I Bubalus bubalis – Rucervus duvauceli -Telescopium telescopium Meretrix meretrix Bankia sp. Assemblage Zone and RAZ-II Tarebia lineata Lymnaea (Pseudosuccinea) acuminata f. Patula Indoplanorbis exustus Gyraulus convexiusculus Parreysia sp. Bellamya bengalensis Pila globosa Gabbia orcula Brotia costula Melanoides tuberculata Corbicula striatella Tarebia granifera Assemblage Zone. The environmental phases of deposition of Holocene sediments of Sundarbans, India as revealed from the Regional assemblage zones indicate Swampy mangrove condition during c. 5000–2000 years BP followed by Supra-tidal fresh water condition since c. 2000 years BP.