About 60-km west of Haflong the Dauki fault appears to be a nearly vertical break and the beds on the two sides show no great difference in age.
[3] West of Haflong, where the fault has little stratigraphical throw, the geosynclinal facies of the Eocene approaches within 7 km of the Kopili beds which are part of the calcareous shelf facies of the Eocene, and which immediately overlie the Sylhet Limestone.
[3] In the North Cachar Hills it overrides all the lower thrusts to rest directly on the Foreland Spur.
The exposed parts of the thrust sheets nearest the plains are composed principally of rocks of Tipam Series.
The exposed parts of the higher thrust sheets are usually made up of chiefly rocks of the Barail Series.