Monitoring landscape response to tectonic forcings in Central Badakhshan-Hindukush-Pamir region using remote sensing data

Abstract

This study deals with the remote sensing analysis of landscape response to tectonic forcings and its implications to understand the regional uplift conditions along the Shiveh River and Shiveh Lake in Central Badakhshan-Hindukush-Pamir region. Quantitative remote and field assessments of process-based laws are needed to accurately describe landscape uplift and denudation with respect to tectonics and climate.We evaluate and calibrate stream power bedrock-incision model under steady state conditions by studying stream profiles in a tectonically active Central Badakhshan region. Previous work in Pyanj region along Tajikistan-Afghanistan boarder and along Yarkun-Chitral region provides spatial and temporal control on rock-uplift rates. SRTM Digital elevation models (DEMs) are used to estimate differences in landscape morphology associated with along-strike northwest to southeast changes in tectonic and climatic conditions. Data is acquired in different stages; first, River longitudinal profiles, stream wise distance, elevation, and drainage area are generated from DEMs. Second, power-law regressions of channel slope as a function of drainage area are used to derive channel concavity and steepness indices. Slope-area data can be generated in a variety of ways, and several methods have been critically evaluated. An uplift rate map of the area has been prepared for further analysis of the drainage network. Siesmotectonic map of the area is also prepared by using seismological data compiled from various resources. The seismicity in this region shows a distinct pattern. Moment tensor solutions show strike-slip components with thrust dominance. The stream profile data can be used to delineate breaks in scaling that are related with the tectonic boundaries. Analysis of stream profiles supports the hypothesis that the study-area channels are in equilibrium with current uplift and climatic conditions. Channel steepness correlates with uplift rate. The uplift rate map shows variable differential uplift rates in this region and it is due to the ongoing complex faulting processes due to India-Eurasia collision. The quaternary faults in the region control local drainage and the deflection of rivers and stream channels is a further evidence of the recent fault activity. Mapping of some quaternary faults on Landsat data also confirms the change in style of deformation in this region.