The Tipam Group consists predominantly of sandy sediments. The
Tipam Sandstone is composed of medium- to coarse-grained
sandstone, in places pebbly to conglomeratic. Johnson and Alam
(1991) concluded that the Tipam Sandstone was deposited in a
bedload-dominated braided fluvial environment. The overlying
Girujan Clay consists mainly of mottled clays with laminated siltstone,
and accumulated in subaerial conditions in lacustrine,flood plain and
overbank environments (Reimann, 1993).