Active tectonics deduced from geomorphic indices and its implication on economic development of water resources in South-Eastern part of Mikir massif, Assam, India

The geomorphic analysis of mountain fronts and related drainage networks can provide valuable insights about the recorded tectonic history of any given region especially when the area shows higher seismic activity in recent times. Therefore, such studies at a regional scale have been frequently undertaken using morphotectonic analysis to delineate areas having higher tectonic activity. Also, study of active tectonics in an area is very important for any development activity especially hydropower projects as it has a direct implication on the stability and life of that project. The area along the South-East part of the Mikir massif is considered as one of the deformed zones of the northeastern region of India which is demonstrated by its seismicity. In the present study, an attempt has been made to study the active tectonic in the study area with the help of eight geomorphic indices and to correlate the results with the recent seismic activity and other ground evidence and finally an assessment of the potential for irrigation and hydropower development project in that area. The results of the study show that the area is tectonically more active along the Kaliyani shear zone and close to the Naga orogenic front. This has also been confirmed by the soft sediments deformation in Quaternary deposits. Despite this higher tectonic activeness, the area is having good potential for the development of small-scale hydropower and irrigation projects.