CHENNAI: Mild tremors were felt in parts of the city as an earthquake measuring 5.1 on the Richter scale hit the Bay of Bengal region Tuesday morning. The epicentre was 10 km below sea level and about 600 km away from Chennai coast.
The quake struck at 7.02 am and officials in National Centre for Seismology confirmed that tremors were recorded in several seismic stations along the east coast. The Indian Tsunami Early Warning Centre issued a release saying, there is no Tsunami threat for India.
Residents of Besant Nagar, Adyar and Porur said they felt the tremors for a few seconds.
VK Gahalaut, Director, National Centre for Seismology, said the location where the earthquake occurred is close to mid-oceanic ridge that is forming. “There are two ridges located 85 degrees east and 90 degrees east. This earthquake has occurred close to one of these ridges. These are actually aseismic ridges, which means they are not supposed to produce earthquakes.”
“But since these are topographically high they are slightly active and can once in a while trigger earthquake,” he explained and added that Bay of Bengal region on Indian tectonic plate was not prone to earthquakes. This Indian plate ranges from Himalayas to Africa to Andaman to 1,000 km off Chennai coast. “It is a very stable tectonic plate and usually region that is away from the boundary of plate is considered safe. This make the earthquake little rare.”
Seismologists in Indian Institute of Sciences, Bengaluru, feel it is puzzling as to why a quake has struck so close to the east coast of India. As per United States Geological Survey (USGS), earthquake is about 447.4 km northwest of Visakhapatnam and 609.1 km west-southwest of Chennai.
In the past, earthquakes have occurred mostly in the region around the Andaman and Nicobar islands which are prone to quakes. Gahalaut said seismic stations in Chennai, Andaman, Port Blair, Bhubaneswar and Visakapatnam have clearly recorded the earthquake.
Many people from Chennai took to social media to report the tremor. “Definitely shaking around 7.05. Rekindled memories of Gujarat 2000,” one user wrote, recounting the tragic 2001 Bhuj earthquake in Gujarat.