Matera Fm

LOCAL: The name is proposed (Shukla et al., 1993) after Matera, a village NW of Bahraich U.P These sediments have been encountered in Matera-1 whereas in all the other wells drilled in the Ganga basin, these Oligo-Miocene (?) sediments have not been encountered so far. Holo: Metra-1, Latitude; 27o 43' 22" N. Longitude: 81o36' 51" E. Drilled depth: 3927 m. The top of the formation is at 3400 m level.

Clayey sandstone. Three litho-untis are identified in the type section. Litho unit I (3280-3400): It consists of dark grey shale, which is moderately hard and silty in nature and shows splintery characteristics. Occasionally siliceous matter has also been reported. It is non-calcareous and pyretic in nature. The pyrite occurs in the form of crystals varying in size (I cm long crystal) indicating highly euxinic environment of deposition. Litho unit II (3190-3280 m): It is a thick sandstone unit with thin intercalations of siltstone and claystone at places. The sandstone is light grey to whitish grey in color, moderately hard, fine to very fine grained, subangular, subrounded highly micaceous and feebly calcareous to non calcareous in nature. Litho unit III (3000-3190):It is composed of intercalation of sandstone, claystone and siltstone and is considered to be a transition between Lower Siwalik and Matera Formation (core analysis report C C # 4). Thickness: 400 m

The palynomorph assemblage recorded in core no 5 and 6 is characterized by Polypodisporites sp., Trialata sp., Inver turopollenites sp., and Caryapollentes sp

The sediments were deposited in a mixed braided/anastamosing and possibly meandering fluvial system