Remote sensing analysis of ongoing deformation in Hazara Kashmir Syntaxis in Northern Pakistan

Abstract

Hazara Kashmir Syntaxis (HKS) is a complex tec-tonic feature in North Western Himalayan Fold and Thrust Belt. Himalayan Frontal thrust starts from the core of the Syntaxis while other faults like Kotil thrust, Riasi thrust and Tanda fault runs along NS directed Jehlum Fault. Seismicity is distributed along all the parts of the Syntaxis i.e. in the core and along the outer loop but decreases southward. The Kangra (1905) and Kashmir Earthquake (2005) are major outputs of the ongoing deformation process and thus gave motivation for this study. This study focuses Kunhar, Kishanganga, Jehlum and Poonch River and their automatically extracted tributaries. The drainage pattern of these rivers is controlled by different tectonic and climatologically changes in the region. Digital elevation models (DEMs) are used for drainage network extraction as it provides elevation information for the land surface throughout the catchment of the area. Drainage network has been extracted from Shuttle radar digital elevation data (SRTM-DEM). Rivers are sensitive to changes in tectonic deformation, adjusting over different periods of time depending on the physical properties of the host rocks, climatic effects and tectonic activity. Thus, the drainage system of a region records the evolution of tectonic deformation. The stream profile analysis of these four rivers provides information about absolute uplift condition in the region. This analysis provides us with different indices and they can later provide us several maps which, integrated in a GIS, allows a better interpretation of the results. We apply fractal analysis to these four rivers and try to study the rigidity of the areas from where they are passing. This is later confirmed with the steepness and concavity indices of the areas to identify the spatial distribution of the different rock types. We can separate various tectonic units and their deformation using knickpoints, concavity and steepness indices and their fractal behavior.