2 weeks ago
Why Maharashtra recorded 29 earthquakes in past 16 days
Maharashtra, a state in India, has felt a lot of small earthquakes lately.
In just sixteen days, people recorded 29 little tremors.
Most of them happened near a city called Nashik.
Scientists call this group of small quakes an 'earthquake swarm'.
An earthquake swarm is when many small earthquakes happen in one area over a short time.
The biggest one measured 4.3, which is still quite small.
Experts say the monsoon rain is the likely reason: water seeps into cracks in the rocks and builds up pressure.
When the pressure gets too high, the rocks release it as tiny shakes.
Experts say this is normal for the region and does not mean a big earthquake is coming soon.
Still, they say buildings should be built strong enough to handle moderate shakes.
Maharashtra recorded at least 29 tremors between July 30 and August 14, with 24 in and around Nashik, four in Palghar and one in Nagpur.
The tremors ranged from magnitude 2 to 4.3 and occurred at depths of between 5 km and 8 km.
The largest tremor, a magnitude 4.3 earthquake, struck Nashik on August 8 at a depth of 5 km.
Experts describe the activity as an 'earthquake swarm', a series of shallow small earthquakes in a localised area with no dominant quake.
Professor Deepankar Choudhury of IIT Bombay attributes the tremors to 'hydro-seismicity', where monsoon water filling cracks in basaltic rock builds pore pressure that releases as small tremors.
- Who
- Residents of Nashik, Palghar and other parts of Maharashtra, with expert analysis from Professor Deepankar Choudhury, an earthquake specialist at IIT Bombay.
- What
- A cluster of at least 29 small earthquakes, described as an 'earthquake swarm', was recorded across Maharashtra.
- Where
- Maharashtra, India - chiefly in and around Nashik and Palghar, with one tremor in Nagpur.
- When
- Between July 30 and August 14, with intense activity on August 6, 8 and 10.
- Why
- Experts attribute the swarm to 'hydro-seismicity': monsoon water filling cracks and pores in the basaltic rock of the Deccan Plateau builds up pore pressure that is released as small tremors.
Key facts
- Total tremors
- 29 between July 30 and August 14
- Location breakdown
- 24 in and around Nashik, 4 in Palghar, 1 in Nagpur
- Magnitude range
- 2 to 4.3
- Depth range
- 5 km to 8 km
- Largest tremor
- Magnitude 4.3 in Nashik on August 8 at 5 km depth
- Busiest day
- August 6 - six tremors in Nashik between 5.41 am and 5.54 pm
- Seismic zone
- Zone III (moderate risk) under Indian Standard IS 1893, Part 1
- Previous swarms
- Palghar witnessed similar activity in September 2023 and February 2019
Quotes
Professor Deepankar Choudhury
Earthquake specialist and IIT Bombay professor
“Owing to its shallow depth, earthquake swarms do not travel very far as it attenuates faster. This means that the impact of Nashik earthquakes will not travel large distances up to Mumbai.”
indianexpress.com
“There is indeed an alarming rise in the number of small earthquakes. However, this is not uncommon.”
indianexpress.com
Sources
Related news
Nashik-Palghar Earthquake Swarm Raises Questions About Seismic Safety
Fresh tremors shake Nashik as seismic sequence continues in Maharashtra
Nashik Records 64 Tremors In A Month; Experts Advise Monitoring
4.3-Magnitude Earthquake Jolts Maharashtra's Nashik; No Casualties Reported
Tremors from 3.2 to 3.5 magnitude shake Maharashtra's Nashik district
