Q) There is no formation of deltas by rivers of the Western Ghats. Why?
A. INTRODUCTION WHAT IS A DELTA:
When a river reaches a lake or the sea the water slows down and loses the power to carry sediment. Some rivers drop so much sediment that waves and tides can’t carry it all away. It builds up in layers forming a delta.
WHY NO FORMATION OF DELTAS IN WESTERN GHATS
West flowing rivers generally originate from Western Ghat Mountains and fall into Arabian Sea. Their journey involves mostly mountainous valley rocky areas and contains low amount of sediment. Western Ghats is situated on the stable peninsular plateau. The peninsular rivers are relatively smaller with each barely accounting 3-6% of drainage system. Moreover, the tributaries of these rivers are very small and hence they don‘t contribute any silt. They receive less amount of rainfall compared to Himalayan Rivers, some of them nonperennial in nature. There are many small rivers which originate from the Western Ghat Mountains and the fall in to the Arabian Sea. Due to the high gradient of Western Ghat these rivers flow with a very high speed. When these fast flowing rivers reach to its mouth it become unable to deposit its slits, due to this reason slits falls in to the sea. West flowing rivers of Western Ghats are small streams, flow rapidly from steep slopes and merged into Arabian Sea covering very short distance. They can form estuaries and not deltas.
REAL TIME EXAMPLE:
Rivers flowing west Narmada, Tapi barely form deltas because they are shorter and swift, does not carry as much sediments, flow in narrow valleys and don‘t have scope to widen and form deltas.
Hence these rivers are not able to form distributaries or a delta before they enter the sea.
HOMEWORK: FIND OUT ABOUT EASTERN GHATS