The Salt Range in the Punjab Region of Pakistan

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5.1 Introduction
Structurally, the Salt Range is the result of tectonic forces imposed during the lateral phases of the Himalayan orogeny in the late Cenozoic time; the occurrence of the thick, incompetent Salt Range formation at the base of the sedimentary sequence has strongly influenced the structure.
5.2 GENERAL STRUCTURES OF THE PAIL-BAHDRAR AREA
Structural features were essentially the result of gravitative flow process (a tectonic diaprisim) involving the subsurface flow of highly incompetent sequence of the Salt Range formation, which consists of red crystalline gypsiferrous marls, gypsum, anhydrite, salt lenses and occasional dolomites and oil shales, due to differential loading caused by the excavation of canyons and ravins by erosional processes. The mechanism could be termed as superficial nontectonic (gravitative) diaprisim. According to Peter and Badgely (1965), “That specific gravity difference may be the prime motivating force for structural uplift of various types, including salt domes” Major structural features of the study area of the central Salt Range include a number of broad flat based synclines separated by somewhat narrow, sharp crested anticlines. As in inverted topography, the synclines occupy spurs, transverse or oblique to the main east-west structural trend of the homocline. The anticlines occur along the deeply eroded gorges and canyons, locally known as
Wahans. Even the side streams seem to follow the anticlinal trends. Axial lines of various anticlines and synclines show no particular parallelism. This Inverted topography is the result of gravitative flow process (a tectonic diapirism) due to the differential loading or unloading caused by the excavation of valleys.
As for as faulting is concerned,...

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...f plastic rocks.
5.4.1 Salt Range Thrust
This Salt Range thrust has brought the older formation of the range upon the less disturbed late Cenozoic sequence that underlies the alluvium.
The thrust zone is usually hidden by recent alluvial deposits and fanglomerates. 5.4.2 Pail Thrust
Along this thrust Amb Formation is exposed over Rawalpindi Group.
On the southern side of Pail city an escarpment face indicates presence of this thrust.
5.4.3 Kalri Thrust
Along this thrust Salt range formation is exposed over Warrcha
Formation
5.4.4 Chambalwala Normal Fault
Along this fault Amb formation is exposed in juxta postion with Hangu
Formation, Lockhart Limestone and Patala Formation. The Paleocene Strata is dipping opposite to the the fault.
5.5 JOINTS
Block joints and slumping are very common in the Eocene limestone which has resulted in forming columnar blocks of limestone.

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