Evolution of the Drainage of Cauvery in South India

It is now realised that the course of the river Cauvery in South India as observed is different from what it was during its inception during late Cretaceous or early Tertiary times. The upper part of the course over the Mysore plateau might have had only slight modifications both headward as well as laterally; but the lower part from Sivasamudram appears to be quite different.

The vast flood plain of Palar, negligible flow even during flood times, the long and broad NE-SW trending dry valley from around Pennagaram in the south to Vaniyambadi in the north extending for about a distance of 65 miles in Tamil Nadu, southeast of Mysore plateau, require satisfactory explanation. It is suggested that the lower part of the Cauvery (Proto-Cauvery) flowed from Hogenakal, through the above valley on to the present course of the Palar river, and that the changes in the course of the rivers in this region were brought about during the Tertiary times, mainly aided by headwa(d erosion by tributaries along fracture zones and fault zones in the region.