Question

how was the peninsular plateau formed the main feature

Answer 1

The Peninsular plateau is a tableland. It is composed of the old crystalline, igneous and metamorphic rocks. The Peninsular plateau is considered the oldest land mass as it was formed due to the drifting of the Gondwana land. The plateau consists of broad and shallow valleys and rounded hills.
  
Peninsular Plateau of India

The triangular shaped Peninsular Plateau of India extends from the south of Indo-Ganga Plain to the Cape Comorin (now Kanyakumari). This plateau is one of the oldest surfaces of the Earth and represents a segregated part of the old Gondwanaland.

Physical features:

The Aravalli range in the west and the Satpura, the Mahadeo and the Kaimur range in the south divide the Peninsular Plateau into two parts:

(i) The Central Indian Plateau in the north and (ii) The Deccan Plateau in the south of it. A brief account of them is given below:

Central Indian Plateau:

The Aravalli mountain, extending between Delhi and Ahmedabad (also Amdavad) , lies in the western flank of the plateau. Once a mighty fold mountain, it has been reduced now to a low one by denudation through hundreds of millions of years.

Features:

In its southern part the Abu Hills contain its highest peak, the Guru Sikhar (1722 m).The Satpura and the Vindhya ranges are two noted ranges of the plateau.The Tapti and the Narmada flow through two rift valleys and the Satpuras (600-900 m) represent a block mountain formed in between these two rights.Dhupgarh (1350 m) is its highest peak.East of the Satpuras run the Mahadeo and the Maikala Range in succession.The arcuate Vindhya range extending from near the western boundary of Madhya Pradesh runs at first eastward and then northeastward.Manpur (881 m) is its highest peak.