Clay Minerals of the Sarada-Varaha Estuary, East Coast of India


  • G.V.S Sarma
  • P. Satyakumar
  • K.U.M Varma
  • E.N.D. Rao
  • M. Subba Rao


Estuarine circulation, sediments, seasonal variability


Seasonal variability of clay mineral suites has been investigated in the Sarada-Varaha estuary, east coast of India. Montmorillonite, illite, and kaolinite occur in significant amounts. Chloride which is present in the adjacent continental shelf sediments is conspicuous by its absence in the estuarine sediments. Montmorillonite shows a general downstream decrease in December when the estuary is in a partially mixed state and an upstream decrease in April associated with a negative state estuary. Illite and kaolinite, in general, register inverse trends correspondingly. The temporal and spatial trends of clay minerals are related to the estuarine and tidal circulation, which form the dominant sediment distribution processes in December and April, respectively.