Blaini Tillites Near Rishikesh and their Origin

The Blaini Formation exposed near Rishikesh, U.P., has been studied and an attempt has been made to describe its origin. It has been suggested that the lower laminated sequence and limestone were deposited during the west base glaciation; it was followed by a period of dry base glaciation during which deposition of massive tillite and limestone took place. The turbulent waters supersaturated with respect to CaCo₃ have probably deposited the limestones. This sequence was followed by an interglacial period during which shales intercalated with siltstone and sandstone, and variegated shales were deposited. The second glaciation (dry base) was of a shorter duration and deposited limestone and upper tillite. Lastly, during the waning phase of the second glaciation, deposition of the topmost bleached pink and grey shales took place.