Residual Mountains - The mountains which are subjected to weathering and erosion for a long time, are lowered down and are called Relief or Residual mountains. The mountains of the Western Ghats, the Aravalli Mountain and the Parasnath mountain of Bihar belong to this type.
These are mountains that are really plateaus that have worn down from erosion.
When a natural disaster takes place then some of the mountains distroy in it, but some of them survive it. the one who survives can be called a residual mountain.
the forces of erosion ,like rivers,glaciers and wind have been acting upon old fold or block mountains for millions of years