The whole area is hilly in character with a gentle slope towards the west.  The eastern portion near the high hills is very irregular being interspersed with ravines.  There is a series of high peaks protruding from the main ridge, the highest of which is the Alwarkurichi peak (1550m). Upper slopes are  rugged, steep and inaccessible in many places.

The underlying rocks are metamorphic consisting of charnokites and other gneisses.   In the main ridges and slopes there are intrusions of huge masses of rocks of granite nature that sometimes covering a considerable area in the most rugged form. 

Disintegration of granite gneisses form a very fine loam with an admixture of  humus.  This varies according to the position of the slope, shallow and stony along ridges,  deep  and fine  in  the valley. Laterite is also found in varying degrees of  disintegration  from  hard rock to fine gravel.    The soil along the stream and riverbanks is of alluvial deposits deep enough for luxuriant tree growth.