Paleozoic Stratigraphy Of The Peshawar Basin, Pakistan

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STRATIGRAPHYIn the southern part of Peshawar basin the presence of Paleozoic rocks were firstconfirmed by Teichert and Stauffer (1965). These rocks were dated as Late Silurian toEarly Devonian based on conodont zonation (Barnett et al., 1966). The following rocksequence was proposed in Nowshera area by Stauffer (1968a).Misri Banda quartzite Post Early DevonianNowshera formation Late Silurian to Early Devonian.Kandar phylliteLate SilurianLatif (1970) found an ampleximorph corals of carboniferous age in the upper partof Nowshera Formation and introduced the term "Pir Sabak Formation" to these rocks.This age was rejected by Talent & Mawson, (1979) on the basis of identification of EarlyDevonian conodonts from stratigraphically highest beds of the Nowshera Formation.Pogue and Hussain (1986) based on systematic mapping and discovely ofCruziana ichnofossils revised and modified the stratigraphic sequence of Nowsheraarea as follows:-Nowshera FormationPanjpir FormationMisri Banda QuartziteAmbar DolomiteEarly DevonianMiddle Ordovician to Late SilurianEarly to Middle OrdovicianCambrian?The rocks of the northeastern pait of the Peshawar basin were assigned thename "Swabi-Chamla Sedimentaly Group" by Martin and Others (1962). They furthersubdivided the group into the following rock formations:-1. Kala Limestone and Dolomite2. Swabi Quartzite3. Swabi Pebbly Shale------ Unconformity -------4. Chamla Quartzite5. Chamla Shale and Phyllite.Davies and Ahmed (1963) reported orthoconic nautiloids from the Kala Limestoneto the south of Swabi and assigned it a Silurian - Devonian age.As a result of the present study, especially the new finds of conodonts, thegeology of the area was further modified and the contact relationships of the rock unitswere elaborated. Unconformities were identified between Ambar Dolomite and MisriBanda Quartzite and between Misri Banda Quartzite and Panjpir Formation.The rocksof Nowshera area were traced towards Swabi on the basis of similar lithology andconodonts revelations. In addition, in Swabi area, conodonts of Late Devonian and
carboniferous age have also been identified. The revised Paleozoic stratigraphic sequenceestablished in the Peshawar basin as a results of the present study is givenbe1 ow.-barFormationPogue and Hussain (1986) proposed the name Ambar Formation for the carbonaterocks found in isolated outcrops of Peshawar basin between Turlandi and SwabiStauffer (1968a) described the rock of this formation exposed near Turlandi area inNowshera Formation. Martin and others (1962) included all the outcrops of AmbarFormation in Swabi area in their "Kala Limestone and Dolomite". The section exposedat Ambar village (Lat. 34' 03' o2"N; Long. 72O 24' 46E) along Swabi - Jehangira roadhas been designated as the type section.The formation is comprised of dolomite, dolomitic limestone, calcareousquartzite and subordinate argillite. Chert in the form of veinlets, nodules and stringersis found at places. The dolomite contains algal laminations and poor development ofstrornatolites. The lower contact of the formation is unconformable with TanawalFormation in Swabi area. The contact is locally marked by a conglomerate bed withcobble and pebble size in a matrix of dolomitic quartzite and argillite. South of Swabi,the lower contact of the formation is covered under the alluvium of Peshawar basin.The upper contact of the formation is also unconformable with Misri Banda Quartziteand is marked by 5-10 metres of maroon coloured shale. In Chingalai area, however, theunconformity is represented by about 10 metres of conglomerate consisting of pebblesand cobbles of quartzite and dolomite in quartzite matrix.The formation has not revealed any fossils except microscopic shell debris in theinterstices of pisoliths from Ambar section. It has been tentatively placed in Cambrianbecause of its stratigraphic position resting above the Tanawal Formation ofPrecambrian age and below the Misri Banda Quartzite of Ordovician age. The formationis correlated with Abbottabad Formation in Hazara on the basis of its stratigraphicpos5tion and lithological similarity.
Page 1 and 2: ~ ~ oBull. l Univ. . Peshawar, 1991
Page 3: from the hills south of Swabi indic
Page 7 and 8: TABLE 1. FOSSIL LIST- --CAI = Conod
Page 9 and 10: The formation is composed of argill
Page 11 and 12: sylvanian age (Table 1 nos. 15, 16
Page 13: Latif, M.A., 1970, Low or Carbonife

Paleozoic Stratigraphy Of The Peshawar Basin, Pakistan

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