Clay Minerals Distribution and their Association with Trace Elements, Calcium and Organic Matter in Inner shelf Sediments off Gangolli, West Coast of India

Abstract

Inner shelf sediments off Gangolli, west coast of India, are mostly silty clays and clayey silts. Clay minerals present in order of decreasing abundance are montmorillonite, kaolinite-chlorite, illite and gibbsite. The relative abundance of kaolinite-chlorite and illite decreases seaward, whereas montmorillonite increases. Clay minerals do not show a distinct association with trace elements; this may be attributed to desorption mechanisms in the marine environment. Organic matter supports the formation of montmorillonite. The presence of calcium also favours the formation ofmontmorillonite but not that of kaolinite-chlorite and illite.