Abstract

The surface sediments of Kodaikanal Lake is situated in the palani hills at an altitude of 2,285 m above sea level, the geo co-ordinates of the lake are lies between 10°14’ N latitude and 77°28’ E longitudes. In the present study determination of grain size and its deposition environment were carried out for surface sediments collected from different parts of the Lake. The study permits to infer the changes in the depositional environment during the period of infilling at the sites. The spatial distribution of Mean size of the sediments varies from medium sand to medium silt, moderately well sorted to very poorly sorted characteristics, near- symmetrical to very fine-skewed type, and falling in platykurtic to very leptokutic nature. United State Department of Agriculture (USDA) textural triangle plot expresses sediments are clustered tightly in silty sand variable, and its type ranges falls within the field of Loamy sand, sand, sandy loam and silty loam fractions. Thus, the Lake sediments are dominance of silt and sand fractions. Multivariant statistics (discriminant analysis) express that the plots fall scattered in Turbidite and Aeolian environment. The Bivariate textural plot falls in Quiet water environment. The polymodel nature of the sediments also implies that transportation by rolling, sliding, saltation and suspension processes in the Kodaikanal Lake.

Keywords: Grain size; Depositional environment; Kodaikanal Lake; Spatial distribution