Distribution and geochemical association of clay minerals on the inner shelf of central Kerala, India

The clay mineral suite of the inner shelf sediments of central Kerala consists of substantial proportions of kaolinite and montmorillonite, with gibbsite in minor quantities. Kaolinite and montmorillonite exhibit an inverse relationship in spatial distribution, which has been attributed to the differential settling velocities of the minerals. The geochemical association suggests a terrestrial origin for all the clay minerals. The aluminous laterites of the coast seem to be the source for the kaolinite and gibbsite. The absence of a relationship between trace elements and detrital clay minerals could be attributed to desorption mechanisms in the marine environment.