![]() ( 2006) further explained that being recent and active structure the geomorphic expression on satellite image clearly depicts that it cuts several tributaries feeding the Jhelum River at its western bank, along ~ 50 km North–South-directed surface trace. Mehdi ( 2005) in the light of seismicity record of HKS in northern Pakistan pointed the Jhelum Fault and stated that it is one of the active faults in Pakistan. ![]() The Jhelum Fault drags the Panjal Volcanics and Triassic limestone southward, along an offset of 38 km (Baig and Lawrence 1987). Abbottabad and Hazara Formations, are intensely distorted in the terrain in-between Balakot and Muzaffarabad localities. ![]() Rawalpindi Group, and Pre-Cambrian meta-sediments, i.e. Baig and Lawrence in 1987 explained the Jhelum Fault as a left-lateral strike-slip fault with reverse ramp, along which the fresh water Miocene strata, i.e. Jhelum Fault is one of the strike-slip faults among them, having sinistral sense of slip, starting from the western limb of Hazara-Kashmir Syntaxis (HKS) and running southward up to eastern Salt Range (Yaseen et al. Stratigraphically rocks of Miocene to Recent age are exposed where the oldest rock units are Murree and Kamlial Formations of Rawalpindi Group (early to middle Miocene), overlain by Siwalik Group rocks (middle Miocene to early Pleistocene) and unconsolidated stream deposits of Holocene (Ahmad et al. Tectonically, the study area is part of the Sub-Himalayas of North Pakistan which covers a part of north-eastern Potwar Plateau and some portion of Kotli District, Azad Jammu and Kashmir (AJK) in the north of Mangla Dam (Fig. The vertical stratigraphic throw along these faults shows small offsets and little east–west shortening, indicating that the major slip along the fault is strike slip. Likewise, the subsurface cross sections show that deformation along the fault zone is accumulated by splay faults from the main Jhelum Fault, which forms a positive flower structure with steep north-eastward dips, which is characteristics of strike-slip movement along Jhelum Fault Zone. The proposed geological map and subsurface model shows that the Jhelum Fault when propagated in the south from Hazara-Kashmir Syntaxis forms a continuous shear zone on surface with some discontinuous exposure of splay faults rather than exposed as continuous discrete break. Moreover, the subsurface model has been proposed using the mechanism of dip-isogons in computer application which connects points of equal inclination or dip on the outer and inner bounding surfaces of a folded layers. Field data along with satellite images are used to construct the geological map. As opposed to the idealized linear movement of a strike-slip fault, the team demonstrated what geologists knew in theory, that shear strain has several stages before final movement along the fault.This research was carried out to understand the nature of strike-slip Jhelum Fault zone and to propose a model for the surface to subsurface deformation pattern. ![]() This is a similar trait we see in many systems on Earth, from rivers finding the easiest path to lower elevations to mammals taking the easiest path from point A to point B.Īs the faults propagate, the team measured how strain is transferred to different parts of the fault, a process that in real life takes millions of years and across many miles. The team found that the faults develop through a "Lazy Earth" hypothesis, whereby the fault propagation takes the easiest path. In one boundary condition, there is a pre-existing fault along the two slabs, in another there is a pre-existing displacement beneath the clay slabs, and in the last example the displacement is in a wider shear zone.Īfter the models were setup, the team moved the two clay slabs in opposite directions in order to measure minute changes as the strike-slip faults developed. After creating two slabs of this kaolin clay, the team setup several boundary conditions on which to test the development of the strike-slip fault. The team made sure the length to depth was scaled appropriately to mimic that on Earth and with the correct viscosity. Hatem built a miniature model of the Earth's crust using kaolin clay. ![]()
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