Structural Analysis of the Kingri Fault Utilising Remote Sensing Techniques; Pakistan
Gohar, Rehman; Irfan, Khan; Sajjad, Ahmad; Abdul, Qayyum
Strike-slip tectonics concomitant with thrusting and folding has been proposed since quite long for the structural architecture of the eastern Sulaiman Range. According to the literature and regional scale published maps of Pakistan, Kingri Fault is an important strike-slip fault of the eastern Sulaiman Range defined by the offsets of geologic and topographic features along its 160 km long map trace and had been active during Holocene. This paper is an attempt to study the nature of Kingri Fault itself and its impact on the structural grain of the eastern Sulaiman range utilising field observations and remote sensing techniques.
A pronounced, north-south trending lineament is identifiable on regional scale Landsat image and digital topographic map of the eastern Sulaiman Range. However a detailed analysis of the Landsat image and topographic map coupled with field observations reveal that no discrete offsets of ridges, stream beds and geological structures are present along the surface trace of Kingri Fault. The geological structures including bedding form lines, fold axes and fault traces are found to be continuous across the well established bearing line of the Kingri Fault without any physical break. As a matter of fact, drag in the bedding form lines and geological structures and change in structural vergence are visible and conclusive features along the map expression of the Kingri Fault.
Two distinct structural domains are present across the trace of Kingri Fault in the eastern Sulaiman Range. A northeast-southwest oriented fold-thrust belt is located to the west of the Kingri Fault with a tectonic transport of the rocks from the northwest and north. Whereas east of the Kingri Fault the structural style corresponds to that of a wrench related deformation comprised of a series of north-northeast trending en echelon folds occupying the highest topographic part of the eastern Sulaiman Range.
The Kingri Fault seems to be a zone of differential simple shear rather than a tear fault which cut across the pre-existing structural grain. This simple shear phenomenon can be attributed to a deep-rooted basement fault acting as a lateral ramp or it may be the result of change in basin configuration in terms of rheological variations and sediments thickness.
AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013