ISSN: 2319-8753 International Journal of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 2, Issue 10, October 2013 Copyright to IJIRSET www.ijirset.com 5741 Heavy Metal Accumulation in the Surface Sediments off Pondicherry, Bay of Bengal, South East Coast of India A.Solai, M.Suresh Gandhi, K.Kasilingam and E.Sriraman Department of Geology, University of Madras, Guindy Campus, Chennai -600025, India Abstract: The Surface sediment samples were analyzed for grain size, carbonates (CaCO3), organic Matter (OM) to obtain a preliminary view of its environmental conditions off Pondicherry along the southeast coast. India. Investigations on the accumulation of heavy metals (Mn, Cr, Cu,Cd, Ni, Pb ,Zn,) in sediments using Atomic Absorption Spectrophotometer at off Pondicherry coast, lying along the southeast coast of India. In sediments, the order was Cr>MN>Pb>Zn>Cu>Ni>Cd. The high concentration of sand in the surface sediments is attributed to the tidal influence at the Virampattinam. The sea water which enters the river suspends the flocculated sediments at the mouth and transports the fine floccules to the water column. The tidal currents also play a major role in removing the fine particles from the river mouth. The value of OM does not show any significant variation towards depth. Keywords: Sediment Texture, CaCO3, Organic Matter and Trace Elements I. INTRODUCTION Sediments from the marginal marine and near shore environments had been studied by a number of geologists for a considerable period of time to determine the process of deposition of ancient sediments. The nature of the sediments is modified by anthropogenic activities and as the impact of these activities has increased more in the following years, sediment geochemistry had been pursued with the objective to assess coastal pollution [1-15]. Accumulation or mobilization of trace elements in the sediments of the aquatic environment [16]. Sediments act as sinks and sources of contaminants in aquatic systems because of their varying physical and chemical properties [17-22]. Most of the chemical changes take place in or close to the sediment/water boundary and, for this reason, it is important to study the geochemical composition of bulk sediments [23-24]. Bay of Bengal has attracted scientists and oceanographers from all over the world with regard to its sedimentation geology, in particular, origin and history of the Bengal Fan sediments [25-26]. Sediments are important carriers of trace metals in the hydrological cycle and they effectively collect or release metals into the surrounding waters; thereby, they can reflect the current quality of an aquatic system [27]. Major elemental analysis effectively represents the composition of the solid fraction being eroded from the continents or the rock types present in the drainage basin of a river [28]. Trace metal enrichment in sediments started with the industrial evolution in Indian sub-continent at the end of the 19th century. As a result, the fluxes of trace metals from terrestrial areas (especially aquatic regions) have increased significantly in developing countries. Since, sediments are often the ultimate depository environment for trace metals in the aquatic environment, the solid-phase distribution can reflect the history of metal accumulation and the weathering pattern of the sediments from adjacent regions [29-32]. Normalization is done by measuring the concentrations of metals in bulk sediments and then dividing them by the percentage of 63 μm size fraction in the bulk sediments in order to obtain the concentration in the fine fraction [33 -35]. The aim of the present study is to identify the source and fate of metals and toxic elements in the study area, and its impact on the environment. Many reports are available on the physical-chemical features of Indian estuaries [36-46]. Heavy metals in the sediment are essential to assess the extent of metal pollution. The distribution of heavy metals in solution has widely been recognized as a major factor in the geochemical behavior, transport and biological effects of these elements in natural waters [47-51]. Moreover, sediment has aptly been called as „Trace element trap‟ [52] because they eventually receive almost all the heavy metals, which enter the aquatic environment [51]. The scavenging by suspending particles results in a large concentration of pollutants being retained in estuarine sediments [53].