Hangu Fm
Type Locality and Naming
Makarwal Gr – lower formation. Holotype section: Lockhart Fort in Samana Range. Hypo: Dhaka Pass in Salt Range. Author: L. M. Davies, 1930.
Lithology and Thickness
Sandstone. In the type area, it consists of sandstone with grey shale intercalations in the upper part. The sandstone is white, light grey and reddish brown, weathering dark rusty brown, fine to coarse grained (in places conglomeratic), and medium to thick bedded. A 2-3 m thick bed of ferruginous pisolitic sandstone occurs at the base of the formation. In the western Kalachitta, Nizampur and Hazara area the formation is mainly composed of ferruginous, oolitic or pisolitic sandstone, siltstone and clay, and contains the Langrial iron ore.
Reference section: In the reference section and TrIR the formation consists of dark grey, rarely variegated sandstone, shale, carbonaceous shale and some nodular, argillaceous limestone. The carbonaceous content increased locally and constitutes coal seams in parts of Surghar Range (Makarwal coal mines).
Thickness: 15-150 m. It is 90 m thick in the type section, 50 m at Hangu, 75 m at Darsamand and 150 m in the Kohat Pass area. It is 45 m thick at Dhak Pass in the SR and 30 m in the SuR. It is less than 15 m in the Nizampur-Kalachitta area and 35 m at Mandeha Banni in Hazara.
Relationships and Distribution
Lower contact
Disconformably underlain by Kawagarh Fm in the Kohat, Kalachitta and Hazara areas. However, in Salt Range and Surghar Range it is unconformably underlain by various Mesozoic and Paleozoic formations, (the youngest being the Lumshiwal Fm of Cretaceous age). In the Salt range as we move from west to east, successively older subcrops are encountered.
Upper contact
Conformably overlain by Lockhart Fm
Regional extent
The formation is widely exposed in Salt Range and Trans Indus Range, and present in subsurface in the Sulaiman Province and Hazara areas.
GeoJSON
Fossils
Foraminifers are the main fossils, and in Salt Range include Operculina cf., O.candalifera, O. subsalsa, Miscellanea miscella, Lockhartia haimei, L. conditi and Lepidocycma (Polylepidina) punjabensis.
Age
Depositional setting
The formation was deposited under transitional marine conditions with coal and carbonaceous clays forming in localized swamps. Laterite and bauxite facies developed at the base during Late Cretaceous-Early Paleocene regressive phase of the sea, which also corresponds with the worldwide K/T boundary.
Additional Information
EMW: Coal, bauxite and iron ore. Oil and gas.