Khojak Fm

Holotype section: Nauroz (30 km NE of Kharan in Kallat). Hypo: Pish Rud, south of Dalbandin. Author: E.W. Vredenburg, 1909. Reference section: Lithological description is not available.

Claystone and Sandstone. It is composed of shale, sandstone and siltstone of mainly of turbiditic and deltaic origin (Qayyum et al. 1996). Locally some beds are carbonaceous with lenses of lignite. The formation has been subdivided into two members, the lower Murgha Faqirzai member, and the upper Shaigalu member.

Murgha Faqirzai member: Shale is the principal rock of this unit and is interbedded with subordinate amount of sandstone and shelly limestone. The member has a conformable lower contact with the underlying Nisai Fm and a transitional upper contact with the Shaigalu member. The lower reaches of Murgha Faqirzai Rud is designated as the type section where the member is about 1,200 m thick.

Shaigalu member: The rocks of the unit are mainly sandstone and shale with conglomerate and limestone at places. Maximum thickness of 6,000 m has been estimated by HSC (1960) from K-KP. It has been measured 3,950 m at Manzaki section by Qayyum et al. (1996). The sandstone is light grey to greenish grey and green, coarse grained, thickly bedded reaching a thickness of 10 m each. The shale associated with sandstone is almost of same amount. Shaigalu, about 50 km SW of Fort Sandeman, is designated as the type section, where the member is 600 m thick, and at Diz it is 1,200 m thick.

Thickness: 900-1,500 m. The formation is 900-1,500 m around the type locality.

Forams: Lepidocyclina dilatata, Nummulites fichteli, N. intermedius, N. vascus. indicate Oligocene age. Some Eocene forams are also reported like Nummulites atacicus, Assilina granulosa and Dictyoconoides cooki.

Murgha Faqirzai sediments were deposited as subaqueous and subaerial facies of delta that existed in the Katawaz remnant ocean, while Shaigalu sediments are interpreted to be deposited by a wave dominated delta.