Topics Covered: Important Geophysical phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc.
What is a lineament?
A lineament is a linear feature in a landscape dictated by an underlying geological structure such as a fault.
Context:
According to a recent study, an unfamiliar lineament is one factor behind frequent earthquakes in northern Assam’s Sonitpur area.
Why there are frequent earthquakes in Assam?
According to the Geological Survey of India (GSI), Sonitpur district lies within a tectonically complex triangular area bounded by the east-west trending Atherkhet Fault, the northwest-southeast trending Kopili Fault and a north-south trending lineament.
Why North east is vulnerable?
- The Siang Fracture, Yemla Fault, Namula Thrust and Canyon Thrust are spread across the northeast and are active along with Main Himalayan Thrust, Main Boundary Thrust, Main Central Thrust and several subsidiary faults.
- The northeast is demarcated as Seismic Zone V, which indicates a zone with high vulnerability.
- The Indian plate is moving northeast toward the Eurasian plate in the Himalayan region, their oblique collision and release of stress and strain accumulated in the local tectonic or fault environments lead to earthquakes.
InstaLinks:
Prelims Link:
What is Lineament?
Identify the following:
- Atherkhet Fault.
- Kopili Fault.
- Siang Fracture.
- Yemla Fault.
- Namula Thrust.
- Canyon Thrust.
Mains Link:
Discuss why North Eastern India is highly vulnerable to earthquakes.
Sources: the Hindu.
