The Ganga Geology - The Ganga: Water Use in the Indian Subcontinent - page 16

Fig. 3.1 Tectonic plates (Rashid, H. E.)
Bengal Basin, old rocks emerged to form the Maghalaya Plateau in the east and the
Chhotonagpur Plateau in the west, as shown in Fig. 3.2.
The narrow part of the Basin, in between the two plateaus, is called the Garo-
Rajmahal gap. Because of proximity of a major subduction fault on the north and a
transform fault on the east, the Bengal Basin and its adjacent areas are tectonically
very active. Large areas were uplifted and some sank, even in recent time. It has been
postulated that these tectonic activities might have been due to a deep and major