day 2 in nammal gorge

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Nammal gorge Day 2 26 On day 2, we went to the Nammal Gorge and observed the following formations which are explained below. 1: Wargal Limestone: Synonym: Noetling (1901) coined the term “The Wargal Group” to a predominantly calcareous unit overlying the AMB Formation in the central Salt Range. The name Wargal Limestone as approved by the Stratigraphic Committee of Pakistan was introduced by Teichert (1966). For the same rock unit, the name “Middle Products Limestone” was used by the Waagen (1879). Type Locality: The type section is near Wargal Village in the central Salt Range. Age: Late Permian. Lithology: The lithology comprises limestone, dolomite and shale. The upper part comprises of dolomite of light to medium grey, brownish grey and olive grey colours. The middle part composes of limestone which is light grey and thin to medium bedded. The base is composed of blackish shale. Fossils: The fauna consists of abundant broyozoans, brachiopods, bivalves, gastropods, nautiloids, ammonoids, trilobitesandcrinoids. Kummel and Tiechert (1970) reported pollen and spores, ostrcodes and conodonts from the Formation. Contacts: The contact of the Wargal Limestone with the underlying Amb Formation is well- defined. The upper contact with the Chiddru Formation is transitional.

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Page 1: Day 2 in nammal gorge

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On day 2, we went to the Nammal Gorge and observed the following formations which are

explained below.

1: Wargal Limestone:

Synonym: Noetling (1901) coined the term “The Wargal Group” to a predominantly

calcareous unit overlying the AMB Formation in the central Salt Range. The name Wargal

Limestone as approved by the Stratigraphic Committee of Pakistan was introduced by Teichert

(1966). For the same rock unit, the name “Middle Products Limestone” was used by the

Waagen (1879).

Type Locality: The type section is near Wargal Village in the central Salt Range.

Age: Late Permian.

Lithology: The lithology comprises limestone, dolomite and shale. The upper part comprises

of dolomite of light to medium grey, brownish grey and olive grey colours. The middle part

composes of limestone which is light grey and thin to medium bedded. The base is composed of

blackish shale.

Fossils: The fauna consists of abundant broyozoans, brachiopods, bivalves, gastropods,

nautiloids, ammonoids, trilobitesandcrinoids. Kummel and Tiechert (1970) reported pollen and

spores, ostrcodes and conodonts from the Formation.

Contacts: The contact of the Wargal Limestone with the underlying Amb Formation is well-

defined. The upper contact with the Chiddru Formation is transitional.

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Wargal Limestone

2: Chiddru Formation:

Synonym: The name “Chiddru beds” was given by Waagen (1891) and “Chiddru Group” by the

Noetling (1901) to the topmost beds of commonly known “Productus Limestone” and is derived

from Chiddru Nala. The name Chiddru Formation was introduced by Dunbar (1932) which is

now formalized.

Age: Late Permian

Type Locality: The type locality is at Chiddru Nala.

Lithology: The formation at the base has a unit of pale-yellowish grey to medium dark grey in

colour, the thickness of this unit ranges from 6 to 13 m. It contains rare small phosphatic

nodules. Overlying this unit are the beds of calcareous sandstone with few sandy limestone.

One of the beds is richly fossiliferous. The topmost part of the Chiddru Formation is a white

sandstone bed with oscillation ripple marks. The hardness of this layer increases with the

increase in the calcium carbonate content.

Fossils: The fauna includes brachiopods, bellerophontids and Plagioglypta, a scaphopoda.

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Contacts: The lower contact is with Wargal Limestone and upper contact with Mianwali

Formation forming paraconformity with it.

Chiddru Formation

Uppermost white bed of Chiddru Formation

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3: Mianwali Formation:

Synonym: The name “Mianwali Series” was used by Gee and later modified by Kummel (1966)

into a formation.

Type Locality:The formation is best exposed in Zaluch Nala and Khisor Range.

Age: Triassic

Lithology: The following three members have been recognized by Kummel (1966).

i. Kathwai Member.

ii. Mittiwali Member.

iii. Narmia Member.

i. Kathwai Member: The unit consists of dolomite in the lower part and limestone in the

upper part. The dolomite is finally crystalline and includes fossil fragments (mainly

echinoderms) and quartz grains. The upper unit is grey to brown glauconitic limestone. The

total thickness of Kathwai Member is 3.7 in Zaluch Nala and 2.4m in Tappan Wahan.

ii.Mittiwali Member: The lithology consists of grey, fine-grained, non-glauconitic limestone

with abundant ammonites. The basal beds consist of limestone. The rest of the unit consists of

greenish to greyish shale, silty shale with some sandstone and limestone interbeds. The unit is

richly fossiliferous.

iii. Narmia Member: The basal bed of Narmia member is a 3 m thick limestone which in

Zaluch Nala consists of dark grey to brown fragmental limestone, sandy in part and containing

brachiopods, bivalves and ammonoids. The rest of the unit consists of grey to black shale with

interbeds of sandstone and lenticular limestone or dolomite. The topmost bed is a grey to

brown massive dolomite.

Fossils: In Kathwai Member the most significant fossils are Ophicerasconnectens,

Glyptophiceras of. G. himalayanumis also reported. The fauna includes endothyracean

Foraminifera, Lingula borealis, rhynchonellids, pectnids, ostracodes, crinoid and ophiuroid

fragments, echinoids, conodonts, fish teeth and a rich assemblage of pollen, spores and

acritarchs. In Mittiwali Member the fauna is dominated by ammonoids and a few nautiloids.

The ammonoids include Ambites, Proptychites, Kingites and Paranorites. The remainder of the

fauna consists of pectinids, ostracodes and conodonts. In Narmia Member brachiopods,

ammonoids, nautiloids, echinoid spines and crinodial remains.

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Contacts: The lower contact with the Chiddru Formation of Late Permian age is marked by a

paraconformity while the upper contact with the Tradian Formation is sharp and well-defined.

Kathwai Member

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Narmia Member

4. Tradian Formation:

Synonym: The name Tradian Formation was introduced by Gee to replace, in part, his earlier

name “Kingrali Sandstone”.

Type Locality: Its thickness is 76 m in the Zaluch section of the Salt Range.

Age: It is regarded as Middle Triassic.

Lithology:The formation comprises of two members; the lower is Landa Member (Kummel,

1966) and the upper is the Khatkiara Member (Shah 1967).

a) Landa Member: It consists of sandstone and shale. The sandstone is micaceous and

varies in colour from pinkish, reddish grey to greenish grey. It is thin to thick-bedded,

with ripple marks and slump structure.

b) Khatkiara Member: It is massive, thick-bedded white sandstone that grades into the

overlying Kingrali Formation with the inclusion of some dolomite beds in its upper part.

Fossils: The formation consists of plant microfossils described by Blame (1970). The lower

Landa Member contains acritarchs whereas the Khatkiara Member yielded only spores, pollen

grains and wood fragments. Some of the essential polynomorphs of Tradian Formation are:

Calamosporalindiana, Cyciogranisporitesarenosus, Aratrisporitespanulatus, Falcisporitesstabilis,

Platysaccusquenslandi.

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Contact: Its lower contact is with Mianwali Formation and upper contact with Kingrali

Formation.

Tradian Formation

5. Kingrali Formation

Synonym: The name Kingrali Dolomite was used by Gee(1945) and later amended as Kingrali

Formation, because several lithological facies are represented. The name originates from

Kingrali Peak in the Khisor Range.

Type Locality: Good sections of the formation occur in Zaluch Nala in the Western Salt Range,

Landa Nala In the Surghar Range and in the Tapan Wahan Gori Tang Nala in the Khisor Range.

Age: Late Triassic.

Lithology:The formation consists of thin to thick-bedded, massive, fine to coarse-grained, light

grey-brown dolomite and dolomitic limestone with interbeds of greenish dolomitic and shale in

the upper part.

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Fossils: Fossils are rare and preserved. Some brachiopods, bivalves and crinoidal remains have

been reported.

Contact:Its lower contact is with the Tradian Formation which is transitional and upper

disconformable contact with Datta Formation.

Kingrali Formation

6. Datta Formation

Synonym: The name Datta Formation was introduced by Danilchik (1961) and Danilchik and

Shah (1967) to replace the name “Variegated Stage” of Gee (1945) and earlier workers.

Type Locality: The type section is located in Datta Nala in the Surghar Range.

Age:Early Jurassic.

Lithology:The formation is mainly of continental origin and consists of variegated (red,

maroon, grey, green and white) sandstone, shale, siltstone and mudstone with irregularly

distributed calcareous, dolomitic, carbonaceous, ferruginous, glass sand and fireclay horizons.

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The fireclay is normally present in the lower part while the upper part includes a thick bed (4 to

7 m) of maroon shale easily recognizable in Salt Range and Trans-Indus Ranges.

Fossils:No diagnostic fossils have been reported from the formation except some

carbonaceous remains.

Contacts:It rests unconformably on the Kingrali Formation and the lower contact with the

Shinawari Formation is gradational.

Datta Formation

Samanasuk Formation

Synonymy

Baroch Lime Stone by Gee(1945),Kioto Lime Stone by Cotter(1933),Kioto Lime Stone by

Middlemiss(1896),Sikhar Lime Stone by Latief(1970)

Type locality:

Samanasuk peak in samanarange .

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Lithology:

In Hazara area the limestone of the Formation is thin to thick-bedded and includes some

dolomitic, ferruginous, sandy and oolitic beds. The thickness of the Formation is 366 m in

Bagnotar section of Hazara area. The lower contact is transitional with Shinawari Formation and

upper contact is disconformable with Chichali formation.Light grayish to bluish gray limestone

with yellow patches of dolomitization(S:33 P:45), oolitic limestone and sandy limestone.

Contacts:

Formation has lower conformable contact with Datta Formation while theUpper contact is

unconformable with Hangu formation

Fossils:

Gastropods, Brachiopods, Bivalves are reported

Age:

The fauna indicates that age in all areas is essentially Middle Jurassic.

Bed of Samana Suk Formation

Hangu Formation

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Synonymy:

“HanguShales” and “Hangu Sandstone” by Davies (1930) and “Hangu Formation” by

Stratigraphic Committee of Pakistan (1973)

Type locality:

The type section of the formation is near fort Lockhart

Lithology:

The formation consists of variegated sandstone, shale, carbonaceous shale and some nodular,

argillaceous limestone in the salt range. A 2 m to 3 m thick bed of ferruginous, pisolitic

Sandstone occurs at the base of unit Lithology can be divided into two parts. Lower part

composed of iron bearing clay, concentration of iron is very low. Upper part consists of

quartose sandstone. Sandstone is fine grained and whitish in color.

Contacts: lower disconformable with Kawagarh Formation. Upper conformable contact with Lockhart

Limestone

Fossils:

Foraminifers with some Corals, gastropods and bivalves have been reported by lqbal

(1972).Haque (1956) recorded abundant Epistominelladubia from Nammal gorge.

Age:

On thee basis of fossils Formation has assigned Early Paleocene age.

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Sandstone of Hungu Formation

Lockhart Limestone:

Synonym: Davies introduced the term “Lockhart Limestone” for a Paleocene limestone unit in

the Kohat area and this usage has been extended by the Stratigraphic Committee of Pakistan to

similar units in other parts of the Kohat-Potwar and Hazara areas.

Type Locality:Fort Lockhart in the Samana Range has been designated as the type locality of

the unit.

Age: Paleocene.

Lithology: In the Salt Range and Trans-Indus ranges, the limestone is grey to light-grey,

medium bedded, nodular, with minor amounts of grey marl and dark bluish grey calcareous

shale in the lower part.

Fossils:The limestone contains abundant foraminifers, corals, molluscs, echinoids and algae.

Lockhartiaconiditi, L. HaimeiMiscellaniamiscella.

Contact: Upper contact conformable and transition with Patala and lower contact

conformable and transitional with Hungu Formation.

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Lockhart Limestone

Patala Formation

Synonymy:

Patala Shales” by Davies (1937), “TarkhobiShales” by Eames (1952), “Hill Limestone” by Wynne

(1873). The present name was given by Stratigraphic Committee of Pakistan.

Type locality:

The section exposed in Patala nala is designated as type section in Salt range

Lithology:

It is mainly composed of splintery shale with interbedded limestone having weathered colour

yellow to rusty brown.

Contacts:

Lower conformable with Lockhart Formation. upper conformable with Nammal Frmation.

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Fossils:

Larger Foraminifers including Lockarciatipprie, Lockarciacondety, Ascilinadandotica,

Ascilinadelcina.Miscilina masala and uppercilina are reported.

Age:

The Formation on the basis of above mentioned Foraminifers is assigned Upper Paleocene age.

Patala Formation

Namal Formation:

Synonym: The term Nammal Formation has been formally accepted by the Stratigraphic

Committee of Pakistan for the “Nammal Limestone and Shale” of Gee (in Fermor, 1935) and

“Nammal Marl” of Danilehik and Shah (1967) occurring in the Salt and Trans Indus Ranges.

Type Locality: The section is exposed in the Nammal Gorge (lat. 32˚ 40˚ N :lon. 71˚ 07’ E) is

the type section.

Age:Early Eocene.

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Lithology: The formation, throughout its extent, comprises of shale, marl and limestone. In

the Salt Range, these rocks occur as alternations. The shale is grey to olive green, while the

limestone and marl are light grey to bluish grey. The limestone is argillaceous in places.

Fossils:Forams and moluscs, Assilinagranulosa, Discocyclinaranikotensis etc.

Contact:Upper contact transitional with sakeser limestone and lower contact with Patala

Formation which is transitional.

Fig 10. Nodular Limestone of Nammal Formation

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Observed Structures in Nammal Gorge:

Tallus structure in Wargal Limestone

Recent Mud Cracks in Nammal Gorge

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Chopboard Weathering in Chiddru Formation

Dome Structure

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Paraconformity b/w Chiddru and Mianwali Fm.

Cross Bedding

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Bivalve Structure

Ammonite Structure

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