EARTHQUAKE ZONES OF INDIA Flashcards
(20 cards)
How much of India’s land area is prone to moderate or severe earthquakes?
Nearly 59% of India’s land area.
How is India divided based on earthquake intensity?
India is divided into five seismic zones based on earthquake intensity.
Which is the most dangerous earthquake zone in India?
Zone 5 – the most seismically active and high-risk area.
Which regions fall under Zone 5?
North-East India, Jammu & Kashmir, Uttarakhand, and parts of Himachal Pradesh.
What is the second most dangerous earthquake zone in India?
Zone 4 – includes regions with significant seismic activity.
Which major city in India falls under Zone 4?
Delhi falls under Zone 4.
Which part of India falls under Zone 3?
Central India, which has moderate seismic activity.
Which seismic zone has the least risk in India?
Zone 2, which includes most of South India.
What is the Central Himalayan Seismic Gap?
A 500 km long fault line in Northwest India that hasn’t had a major earthquake in centuries, indicating potential strain buildup.
Why is the Delhi-NCR region considered at risk for a major earthquake?
It is close to multiple tectonic faults like the Mahendragarh-Dehradun Fault (MDF), Sohna Fault (SF), and Mathura Fault (MF).
What is a seismic gap?
A fault zone that hasn’t experienced quakes for a long time but is expected to release built-up strain in a major event.
Why is Northeast India highly earthquake-prone?
Due to complex tectonic activity between the Himalayas and the Arakan Yoma belt.
Name three major faults in the Northeast India region.
Po Chu Fault, Kopili Fault, and Jiali Fault.
What is the Kopili Fault Zone?
A 300 km long, 50 km wide fault that runs through Assam and Manipur, making the region highly seismic.
What is the Himalayan Thrust Fault?
A tectonic boundary where the Indian Plate subducts under the Eurasian Plate, causing high seismic activity.
Which Indian dam is linked to a major earthquake due to reservoir-induced seismicity?
Koyna Dam in Maharashtra, associated with the 1967 Koynanagar Earthquake (6.3 magnitude).
What is reservoir-induced seismicity?
When water pressure from large reservoirs alters stress on faults, triggering earthquakes.
How does the Indian Plate movement contribute to earthquakes?
The Indian Plate is colliding with the Eurasian Plate, leading to high seismic activity in the Himalayan region.
What is the most earthquake-prone state in India?
Arunachal Pradesh, due to its location in Zone 5 and tectonic activity.
Why is the Western Ghats region less prone to earthquakes?
It is located in Zone 2, away from major tectonic boundaries.
