Geology of Kohat basin.

1. Kohat Sub-basin
 Located West of Potwar Sub-basin
 Bounded by;
 North: Parachinar Ranges
 South: Bannu Depression
 West: Kurram Fault
 East: Indus River
 Age of Kohat Sub-basin ins 208 million years dated to
Jurassic
 Sequence exposed here are from Jurassic to Pliocene.
 Kohat Sub-basin divides into three areas
 Northern Kohat
 Southern Kohat
 Western Kohat

2. Northern Kohat (Panoba Section)
 9. Lei Conglomerate
 8. Siwalik Group
 7. Rawalpindi Group
 6. Kohat Formation
 5. Kuldana Formation
 4. Sheikhan Limestone
 3. Panoba Shale
 2. Patala Formation
 1. Lockhart Formation
 Southern Kohat (Bahadhurkhel Section)
 9. Lei Conglomerate
 8. Siwalik Group
 7. Rawalpindi Group
 6. Kohat Formation
 5. Kuldana Formation
 4. Jatta Gypsum
 3. Bahadhurkhel Salt
 2. Patala Formation
 1. Lockhart Formation
 Western Kohat (Samana Range)
 5. Hangu Formation
 4. Kawagarh Formation
 3. Lunshiwal Formation
 2. Chichali Formation
 1. Samana Suk Formation
Overall Sequence
Lei Conglomerate
Siwalik Group
Rawalpindi Group
Kohat Formation
Kuldana Formation
Jatta Gypsum / Sheikhan Limestone
Bahadhurkhel Salt / Panoba Shale
Patala Formation
Lockhart Formation
Hangu Formation
Kawagarh Formation
Lunshiwal Formation
Chichali Formation
Samana Suk Formation

3. Samana Suk Formation
 As discussed under Salt Range.
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Surghar Group
 Contains the following formation, the type
section for these formation is in the Surghar
Range.
 But these are also exposed in the Kohat Sub-basin.
 Formations are of Cretaceous age;
 1. Chichali Formation
 2. Lumshiwal Formation
 3. Kawagarh Formation

4. 1. Chichali Formation
 Chichali term was introduced by Danichik 1961 and Danilchik et
al 1967 For;
 Beleminites beds of Spatt 1939 and Gee 1945 in Surghar Range
 Spiti Shale of Middlemiss 1896 and Cotter 1933 in Kalachitta
Range
Type Locality
 Chichali Pass, Surghar Range (lat. 330 00’ 00’’ N and 700 25’
00’’ E)
Lithology
 Sandstone+Shale
 Over all formation having dark green, greenish grey, sandy silty,
weather rusty brown glauconitic sandstone and shale interbeds
 Shale and sandstone have phosphatic nodules and pyrite, shale
may be carbonaceous at places.

5. Thickness/Distribution
 Well distributed in Trans Indus Ranges, Kala Chitta Range, Hazara and Kohat
areas.
 At type locality, thickness varies 55-70m
 In western Kohat (Samana Range) 15-20m
 In Kala Chitta Ranges 12-27m
 Hazara area 33m
Fossils
 Abundant beleminites, in sandstone, bivalves and ammonites are also
present.
Age
 Early-Cretaceous
Contact
 Lower: conformable with Samana Suk Formation
 Upper: Gradational with Lumshiwal Formation
Environment of Deposition
 Shallow Marine (Shelfal)

6. 2. Lumshiwal Formation
 Gee 1945 proposed the name Lumshiwal Sandstone
then Stratigraphic Committee of Pakistan Formalized
the name Lumshiwal Formation for the;
 Giumal Sanstone of Middlemiss 1896 and Cotter 1933
 Mari Sanstone series of Davies 1930 at Hazara Kala
Chitta and Kohat area.
Type Locality/Section
 Name derived from Lumshiwal Nala (lat. 320 05’ 00’’ N
and long. 710 09’ 00’’ E)
 The type section lies 1km from Lumshiwal Nala by
Fatmi 1977.

7. Lithology
 Shale+Sandstone+Limestone
 At type locality
 Shale: silty and sandy, glauconitic shale at the base
 Sandstone: thick bedded, light grey, current bedded
sandstone, sandstone is feldspathic, ferruginous and
contains carbonaceous material in upper part
 Samana, Hazara, Kala Chitta Ranges
 Sandstone have interclation of Limestone; rusty brown and
sandty with abundant fossils of echinoderm and forams etc.
Thickness/Distribution
 Trans Indus Ranges, Kala Chitta, Kohat, Hazara
 Thickness at type locality 80-120m
 Chichali pass 38m
 Samana Range 194m
 SE Hazara 50m

8. Fossils
 Beleminites, ammonites, gastropods,
echinoderms, brachiopods etc.
Age
 Middle Cretaceous
Contact
 Lower: gradationla Chichali Formation
 Upper: conformable with Kawargh Formation
Environment of Deposition
 Shallow Marine

9. 3. Kawagarh Formation
 The name was introduced by Day A. as Kawagarh Marl
 Stratigarphic Committee of Pakistan approves it to be Kawagarh
Formation
 Before that various workers has given various name at various
places as;
 Sub-lithographic limestone in Samana Range by Davies 1930
 Darsamand Limestone in W. Kohat by Fatmi and Khan 1966
 Dunbar Limestone by Khan and Ahmad 1966; Sattu Limestone
by Calkins and Martin 1968; Chanali Limestone by Latif 1970, in
Hazara area.
Type Locality
 After Kawagarh Hills, North of main Kala Chitta Range in Attock
district (lat 330 45’ 30’’ N and long. 700 28’ 30’’ E)

10. Lithology
 At type locality
 Consists of dark marl with calcareous shales weathers into
light grey, brownish grey and argillaceous limestone.
 In Western Kohat
 Formation is divisible into two member
 Upper: Tsukail Tsuk Limestone
 Named after Tsukail Tsuk Peak, North of Darsamand (lat. 330 28’ 33’’
N, long. 700 38’ 09’’ E)
 A grey, sub-lithographic, thick bedded, escarpment forming,
limestone with common smaller forams.
 Lower: Chalor Silli Member
 Named after Chalor Silli Village, Samana range (lat. 330 26’ 25’’ N,
700 38’ 16’’ E)
 A light grey, olive grey, lithographic to sub-lithographic, thin-medium
bedded limestone with subordinate calcareous shale and marl
interclation with smaller forams and rare ammonites.
 In Eastern Kohat
 Dolomitic limestone occurs at lower part

11.  Hazara area
 The formation is typically a thin to thick bedded limestone similar to W. Kohat but there is
another member;
 Nara Sandstone Member:
 Named after the village Nara, SE Hazara (lat. 350 59’ 00’’ N, long. 730 13’ 30’’ E)
 Member having grey, brownish grey to dark grey, thick bedded, calcareous with some
limestone interbeds.
 Thickness/Distribution
 In eastern Kohat 70-90m
 In western Kohat 110m
 In Kala Chitta (type locality) 40-70m
 Hazara varies 45-200m
Fossils
 Small forams, corals, poorly preserved ammonoids
Age
 Late Cretaceous
Contact
 Lower: conformable with Lumshiwal Formation
 Upper: disconformable with Hangu Formation
Environment of Deposition
 Marine (Open)

12. Makarwal Group
 As done in the Salt Range
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Eocene Stratigraphy of Kohat Area
(Cherat Group )
 Includes the following formation
 Kohat Formation
 Kuldana Formation
 Jatta Gypsum / Sheikhan Limestone
 Bahadhur Khel Salt / Panoba Shale

13. 1. Bahadhurkhel Salt
 Kohat Saline series by Gee in 1945
 Bahadhurkhel Salt was introduce by Meisner 1968
Type Locality
 Bahadhurkhel salt quarry (lat. 330 09’ 54’’ N, long. 700 59’ 53’’ E)
Lithology
 Salt: white with black stringers at places
 At other places: dark grey to black
Thickness/Distribution
 Outcrop at Bahadhurkhel is about 12km in length and half km wide.
 Thickness at type locality is 480m
Fossils
 Only plant leaves
Age
 Early Eocene (Superposition)

14.  Contact
 Lower: conformable with Patala Formation
 Upper: conformable with Jatta Gypsum
Environment of Deposition
 Evaporitic
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2. Jatta Gypsum
 Jatta Gypsum by Meisner 1968
 For upper part of Kohat series of Gee 1945
Type Locality
 Jatta Gypsum quarry (lat. 330 18’ 00’’ N and long. 710 17’ 00’’
E)
Lithology
 Gypsum: greenish, white in colour, massive bedded, hard
having interclation of clay of red, green at different intervals

15. Thickness/Distribution
 Jatta Gypsum covers an area in southern kohat
about 130km long and 15-30km wide
 Thickness ranges form 25-40m
Fossils
 No fossil have been reported
Age
 Early Eocene (due to superposition)
Environment of Deposition
 Evaporitic

16. 3. Panoba Shale
 Term introduced by Eames 1952
 Green clay by Wynne 1879
 Green shale by Pascoe 1926
 Green clay and sandstone by Gee 1934
Type Locality/Section
 The section is exposed south of Panoba village (lat. 330 37’ 00’’
N and long. 710 35’ 00’’ E)
Lithology
 Shale with subordinate sandstone
 Shale: colour is olive green, greenish grey and calcareous towards base
Thickness/Distribution
 Only confined to Kohat area
 Thickness at type locality 100m, Tarkhobi 40m and Uch Bazar 160m

17. Fossils
 Microfossils like ostracodes, forams, mollusks
Age
 Early Eocene
Contact
 Lower: conformable with Patala Formation
 Upper: conformable with Sheikhan Formation
(Panoba Section)
unconformable with Kohat Formation
at Utch Bazar
Environment of Deposition
 Shallow Marine

18. 4. Sheikhan Formation
 Sheikhan Limestone by Davies 1926
 Gypsiferous beds of Eames 1952
 Formalized by Stratigraphic Committee of Pakistan as Sheikhan
Formation
Type Locality
 The section is exposed in Sheikhan Nala (lat. 330 35’ 00’’ N and
long. 710 30’ 00’’ E)
Lithology
 At type locality
 Limestone with subordinate shale
 Limestone is yellowish grey, thin bedded, nodular
 Shale is gypsiferous at the top of the formation
 At Panoba Section
 Limestone with subordinate shale at lower part
 While argillaceous limestone interclated with dusky brown shale with
gypsum beds near at top

19. Fossils
 Forams, mollusks, echinoids, and corals
Age
 Early Eocene
Contact
 Lower: conformable with Panoba Shale
 Upper: conformable with Kuldana Formation
Environment of Deposition
 Shallow Marine

20. 5. Kuldana Formation
 Kuldana beds by Wynne 1874
 Kuldana series by Middlemiss 1896
 Varigated shale by Pinfold 1918
 Lower cherat by Eames 1952
 Mamikhel Clay by Meisner 1968
 Kuldana beds by Latif 1970
 Formalized by Stratigraphic Committee of Pakistan as Kuldana Formation
Type Locality
 Village Kuldana at lat. 330 56’ N and long. 730 27’ E, north of Murree Hill
Station
Lithology
 Shale; with crimson red, purple, brown buff, pale yellow in colour and marl;
with brown buff with few beds of gypsum and occasional beds of sandstone,
limesotne conglomerate with little dolomite
 Hazara area
 Formation is mainly composed of Shale and Marl
 Kala Chitta
 Mainly shale
 Kohat Area
 Predominantly limestone, sandstone, dolomite

21. Thickness/Distribution
 Hazara, Kala Chitta, Kohat area; 150m
Fossils
 Forams, gastropods, bivalves, vertebrate fossils
Age
 Early to Middle Eocene
Contact
 Lower: conformable with Sheikhan Formation
 Upper: conformable with Kohat Limestone
Environment of Deposition
 Shallow Marine

22. 6. Kohat Formation
 Eames 1952 named this formation as Kohat Shales and divided
it into three units as’
 Nummulitic Shales
 Kohat Limestone
 Sirki Shales
 Stratigraphic Committee of Pakistan approved this formation to
be Kohat Formation with three subdivision of Meisner as;
 Kaladandh Member
 Sadkal Member
 Habib Rahi Member
Type Locality
 Kohat-Khushalgarh Highway at lat. 330 27’ N and long. 710 35’
E.
Lithology
 Subordinatng Limestone and shale
 Mainly divided into three members as;

23. a. Kaladandh Member
 The lower member, having limestone of light grey, hard massive with
shale and fossiliferous
b. Sadkal Member
 Middle one, having shale greenish grey, calcareous with subordinate
limestone.
c. Habib Rahi Member
 Upper one, having limestone interbedding are dominated in kohat area
and highly fossiliferous in Nummulites also called as Nummulitic
Limestone.
Thickness/Distribution
 130m at Utch Bazar, 50m Mamikhel, 170m at Chilli Bagh.
Fossils
 Forams abundant, mollusks

24. Age
 Early to middle Eocence
Contact
 Lower: conformable with Kuldana Formation
 Upper: unconformable with Murree Formation
Environment of Deposition
 Shallow Marine (Shelfal)

25. Rawalpindi Group of Miocene age, Siwalik Group
of Pliocene age and Lei conglomerate has
already been discuss in detail
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