Surface microtextural study of detrital quartz grains of innershelf sediments off central Kerala coast

Abstract

Surficial sediments of the near- and outer- innershelf zones contain considerable sand proportion. To examine their depositional history, microtextural study of detrital quartz grains with granulometry and multivariate discrimination analysis are made. The microtextural study indicates the presence of grains with mechanical features formed under beach and nearshore environments. Higher degree of chemical alteration observed in the outer- innershelf samples suggests longer residence time in marine environment. Granulometry and multivariate analysis reveal the presence of sandy sediments deposited under beach and aeolian conditions. From the studies it is inferred that the sands of outer-innershelf are the beach deposit of Holocene period.