Remote sensing analysis of quaternary deformation in the Hindukush-Pamir region

This study deals with the remote sensing analysis of Quaternary faults and their implications for the understanding of the dynamics of the Hindukush-Pamir intermontane region. Recent tectonic activity in Central Badakhshan is a result of the collision between Indo-Pak sub-continental and Eurasian plates. Mapping active structures is an important issue in order to assess seismic hazards and to understand the Quaternary dynamics of the region. This study is based on rectified Landsat and SRTM data.An important step is the Pansharpening of the data, which preserves the multispectral information but with the panchromatic spatial resolution. We map previously recognized and new active faults in detail, and have categorized individual features on the basis of their geomorphic expression. The stream profile analysis in this region using SRTM data gives information about the tectonic influence on the local drainage network. The derived steepness and concavity index values show variable uplift conditions in this region. Quaternary faults sometimes cut across antecedent structural grain. They are manifested as pronounced lineaments across the Hindukush-Pamir region. These faults control local drainages and make shutter ridges. The deflection of rivers and stream channels is further evidence of the recent fault activity. In many places in central Badakhshan, older thrust faults appear to be offset by northwest-trending strike-slip faults; Landforms and other geomorphological evidence indicate that most of these zones have a right-lateral sense of movement. The marked difference between the older N-NE and the younger N-NW trending features indicates a clear change in the deformation style from the past contractional period, to a more recent phase of shearing and northwest-directed crustal strike-slip deformation. Additional studies using higher-resolution imagery and field investigations are needed to more accurately characterize these faults.