Drainage Pattern and its Bearing on Relative Active Tectonics of a Region: A Study in the Son Valley, Central India

Abstract

The paper emphasis the participation of different geomorphic parameters related to various characteristics of drainage in evaluation of active tectonics of an area. For the purpose, the morphotectonic evaluations of the Son valley, central India have been carried by involving various drainage related geomorphic indices viz., stream-gradient index (SL), hypsometric integral (HI), drainage basin asymmetry (AF), valley floor height and width ratio (Vf), transverse topographic symmetry factor (T), mountain front sinuosity (Smf), drainage basin shape (BS) and sinuosity index (SI) and relative rock strength (RRS) for classification of relative index of active tectonics (RIAT) in geographic information systems (GIS) environment to understand the role of active tectonics in geomorphologic evolution of the studied region. The established RIAT classes through field validations categorize the valley into four zones such as class 1- low activity (RIAT 3.29). The sub-dendritic, rectilinear and parallel linear drainage styles in RIAT classified basin reveal the traverse of a network of seventeen faults in association with two major faults namely Son-Narmada-North Fault (SNNF) and Son-Narmada South Fault (SNSF) in variable associations of rocks and multiple types of structural elements present in the Son valley. The signature of vertical upliftments may indicate the instability tectonic activities along the identified network of faults associated with SNNF and SNSF. Hence, the study suggests variable tectonically activeness of area in the Son valley.