Himalayan or Indus Suture Zone- Found to be tectonically active.

The Himalayan or the Indus Suture Zone (ISZ) in the Ladakh region has been found to be tectonically active. Suture zone is the zone where the Indian and Asian Plates join each other. Until now, it was supposed to be a locked zone.

Highlights

  • This new study would have major implications on the earthquake study, prediction, understanding the seismic structure of the mountain chains and  its evolution.
  • This study was conducted by a group of scientists from Wadia Institute of Himalayan Geology (WIHG) in Dehradun.
  • Study was published recently in the journal ‘Technophysics’.

What has been observed?

It has been observed that sedimentary beds are tilted and thrust broken. There is a remote fault zone in the suture zone which is tectonically active. The rivers at this zone are associated with uplifted terraces. The bedrock further shows brittle deformation at a shallower depths. This region of the Indus Suture Zone (ISZ) was last active some 78000 — 58000 years back. However the recent Earthquake of 2010 near the village Upshi that occurred due to a thrust rupture. The study also says that the Suture Zone of the Himalayas has been active in the recent years of the earth history. This is thus one of the major reason for the frequent earthquakes in the northern India recently. Himalayas comprise of three thrusts- Main Central Thrust, Main Frontal Thrust and Main Boundary Thrust. The study says, Main Frontal Thrusts are locked and the overall deformation is occurring in the Main Frontal Thrust.

Thrusts

Thrusts are the faults that are gentle curved or fractures in the rocks of the Earth’s crust.

Suture Zone

When two fault zones join together, it forms the Suture zone. It is usually found in mountain ranges. The Himalayan Suture Zone is also called the Indus Suture Zone or Indus Yarlung Tsangpo Suture Zone. It is the zone of collision between  Indian Plate and Ladakh Batholith.