Research

Earth, Atmosphere & Environment Sciences

Title :

Revisiting the Himachal Himalaya to test different tectonic models and their implications to Himalayan geodynamics

Area of research :

Earth, Atmosphere & Environment Sciences

Principal Investigator :

Dr. Arun Kumar Ojha, CSIR - National Geophysical Research Institute, Telangana

Timeline Start Year :

2022

Timeline End Year :

2024

Contact info :

Equipments :

Details

Executive Summary :

The Himalaya, a 2500-km-long mountain range, is a classic example of a continent-continent collision between the Indian and Eurasian plates around 59-61 Ma. It is divided into different litho-tectonic units, including the Sub Himalaya (SH), Lesser Himalayan Sequence (LHS), Greater Himalayan Crystalline (GHC), and Tethyan Himalayan Sequence (THS). The southern boundary of these units is marked by the Himalayan Frontal Thrust (HFT), Main Boundary Thrust (MBT), Main Central Thrust (MCT), and South Tibet Detachment (STD). Despite over eight decades of research, several questions remain unanswered on the building of the Himalayan orogenic belt. Several tectonic models have been proposed to understand the evolution of the Himalaya, but none have been successful in the Himachal Himalaya. The 'Channel flow' model suggests that the low-viscosity lower and middle crustal part of the Tibetan crust migrates to the south as the GHC rocks, bounded between the MCT and STD. However, this model fails in the Himachal Himalaya. The present research project aims to examine different tectonic models using mesoscopic and microscopic structural analysis along with ⁴⁰Ar/³⁹Ar geochronology in the Himachal Himalaya. The study area is selected due to its easy accessibility, well-studied geology and tectonics, and lack of understanding of the geometry and complexity of large- and small-scale structures. The outcome of the research will help constrain the timing of MCT and STD activities and test the validity of existing tectonic models.

Total Budget (INR):

27,41,580

Organizations involved