Question

What is the difference between dissected and intermontane plateau

Answer 1

When a plateau is covered  by mountains on all sides, it is called an Intermontane plateau. The Tibetan plateau, the Bolivian plateau are examples of the Intermontane plateau.

Volcanic plateaus are produced by the volcanic activity. The lava which flows down from the volcano, it accumulates and form a plateau. The Deccan Plateau  is an example of the volcanic plateau.