Neotectonic activity in the Markanda and Bata river basins, Himachal Pradesh, NW Himalaya: A morphotectonic approach

In an orogenic belt like the Himalaya, expressions of neotectome activities are numerous, manifested mainly by faulting and tilting of Quaternary deposits (alluvial fans and river terraces), fault controlled channels, river capture, etc., well-expressed on satellite images. Studies on quantification of block tilting of river basins in the Himalaya have not been attempted so far. The aim of the present communication, therefore, is to quantify block tilting using morphotectonic parameters, such as basin asymmetry factor (AF) and transverse topographic symmetry factor (TF) in the uppermost courses of the Markanda and Bata rivers (Himachal Pradesh). The AF values of 89.34 and 25.69 and the TF values of 0.77 and 0.67 due south-southwest respectively for Markanda and Bata indicate that the northern segments of the Markanda and Bata river catchments are tilted south with respect to the trunk streams. Fault and lineament controlled channels of the Bata and Markanda rivers and some of their tributaries further corroborate the neotectonic activities in this region.