Did the ancestral Indus Flow into the Ganges Drainage?
Abstract
The Late Miocene, Pliocene and Pleistocene Upper Siwalik Group molasse sediments of the Eastern Potwar Plateau are shown to include two distinctive sandstone complexes. The older sandstone complex is white colored and carries granitic pebbles. The younger sandstone complex is brown colored and carries quartzite and igneous pebbles. Paleocurrent measurements together with preliminary provenance analysis suggest that the white sandstones were deposited by an ancestral Indus River which flowed to the east-northeast across the Eastern Potwar Plateau. This river system was replaced between 4.5-5.0 MY ago by a southward flowing ancestral Jhelum River. It is possible that the ancestral Indus River may have drained into the Bay of Bengal rather than into the Arabian Sea.
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