Isha Fm

Holotype section: Isha Check Post, North Waziristan. Author: S. Ahmed et al., 2000. Reference section: None.

The formation typically consists of thick bedded to massive limestone with minor shale intercalations. Limestone. At the type locality, the limestone is mostly dark grey to blue in color, and weathers to light grey and to brownish colors. At places, the limestone is thin to thick bedded, hard and contains some secondary calcite veins, chert nodules, ooides, pisolite and pellets. Its texture varies from fine grained, sublithographic to oolitic, reefoid and shelly. In the upper part, the limestone is fairly jointed, fractured and calcite veins are present in these openings. The limestone forms high ridges throughout the area.

Thickness: 100 m at the type locality.

Belemnites, algae, corals, bryzoans, brachiopods, crinoids and fragments of molluscs are found.