| Both the Satyamangalam and Talamalai ranges have 17 and 9 remarkable streams respectively. In Satyamangalam range, drainage is carried by numerous small streams which empty themselves into two big rivulets called the Jodumatti and Haleru hallas. In Talamalai range, the Talamalai basin is chiefly drained by Jogatti and Balapadugau hallas which unite to form Halibidda halla again flowing northwards into Mysore. |
| 1.2.2. Geology, Rock and Soil |
| The rocks found in this area belong to the gneissic series of Indian Rock series, mainly metamorphosed rocks belong to the Archean Complex considered 4500 million years old. |
| Soil consists of a rare kankar pellets and laterite, calcareous tufa and alluvium of Cauvery. |
| Mineral wealth of this area is not insignificant. Finest quality of Flespar, Gorundum as deposited Crystals and Muscovite are abundently noticed in this area. Local tribal women in these settlements collect Barite mixed with quarts and flespar as `kolakkalu’, which is powdered and used for drawing geometrical patterns and other pictures on the ground in front of their houses and also they sell these stones through co-operative societies. |
| 1.2.3. Claimate |
| According to the international transitional bioclimate, the range falls under `36th, medium trophical transitional bioclimate’. The general conditions obtaining in the North Coimbatore division, ranges from `Tropical accentuated bioclimate’ in the plains to `Tropical moderate bioclimate’ on the plateau which is characterised by the monthly temperature above 200C. |
| 1.2.4 Winds |
| The plateau forests are subjected to strong and gusty winds blowing from a south-westwardly direction during the period of south-west monsoon (June-September). The wind is mostly dry and only aid in quickening the pace of evaporation. In may, thunder storms with occasional bursts of rain are common on the plateau. |
| 1.2.5. Rain fall |
| The annual rainfall of the range is ranging from 500-1500mm. with a prolonged spell of dry period. However, the annual rainfall varies from year to year and place to place. Though the division gets the benefit of both the monsoons, the bulk of the rain fall is derived from the north-east monsoon during the months of September, October and November. The period from January to April is usually dry though occassional showers may occur unpredictably. |
