Hinglaj Fm
Type Locality and Naming
Siwalik Gr. – lower formation in the Kohat-Margala Province (Ko-MP and the Trans Indus-Potwar Province (TrI-PP). Holotype section: Within Makran Flysch Province (MFP) of the Balochistan Basin. (Hinglaj hills provide best exposures). Author: E. W. Vredenburg, 1906. Reference section: None.
Lithology and Thickness
Sandstone. The formation is composed dominantly of sandstone with shale, subordinate shelly limestone and minor conglomerate. The sandstone is grey, greenish grey, pale yellow brown to brown and weathers to various shades of brown. It is fine- to coarse-grained, gritty to pebbly in places and usually calcareous.
Thickness: 3,030-4,545 m. At Hinglaj hills, it is 4,000 m thick. The formation is 4,545 m thick in Talar area and 3,030 m in Jiwani area (both of these are reference sections).
Relationships and Distribution
Lower contact
Conformably underlain by Khojak Fm (transitional) in Axial Belt, except in areas north of Bela where it is conformably underlain by the Nari Fm. Conformably underlain by Talar Fm or Parkini Fm (Talar might be partly coeval) in Makran Flysch Province of Balochistan Basin.
Upper contact
Regional extent
Restricted to Axial Belt (Arenaceous Zone), and to Makran Flysch Province (where the lower coeval facies is called the Talar Fm.).
GeoJSON
Fossils
In Axial belt, the formation has yielded Oligocene and Late Oligocene-Miocene foraminiferal assemblages like Assilina mamilla, Fasciolites Borealis, Discocyclina undulate, Lepidocyclina bionfordi, L. dilatata, Nephrolepodima sp., Nummulites atacicus, N. fichteli, N. intermedius, Spiroclypeus sp. etc.
Age
Depositional setting
Additional Information
In the Makran Flysch Province from Late Miocene to Early Pleistocene, concurrent with subduction related compressional structuring; there has been a period of slope, shelf and coastal plain progradation during deposition of sandstone-shale package of Pliocene Talar Fm / Hinglaj Fm and the Plio-Pleistocene Chatti Fm (Kazmi and Abbasi, 2008).