BHUBANESWAR: A 5.1-magnitude earthquake that hit India’s eastern coast on Tuesday morning was “unusual” , said scientists, who suspect an undetected fault system deep inside the sea can cause future disasters as a probe team investigates the unprecedented seismic activity.
The 6.10 am quake’s epicentre was located at a depth of 91 kilometres beneath the sea surface, about 286 km from Puri, but it sent strong tremors across Odisha, West Bengal and Bangladesh, the National Center for Seismology (NCS) said.
As quake alerts on smartphones went off, many people rushed out of their beds.
Some people in Paradip and Puri rushed to the seashores. “When I saw the news of the earthquake on TV, and the epicentre of the quake to be the Bay of Bengal, I came to the sea beach to check if there was any change in the sea,” said Rajanikant Swain, a resident of Puri.
Scientists said they are not amused and have decided to dig deep into the sudden quake.
While the Geological Survey of India (GSI) has formed separate teams from Odisha and West Bengal to conduct a study on the latest earthquake, Ajay Kumar, scientist, Tsunami Early Warning Centre, Indian National Center for Ocean Information Services (INCOIS) Hyderabad said it was an ‘unusual seismic event’ that demands further studies.
“Most of the earthquakes occur at the tectonic plate fault boundaries where plate junctions are present. Many earthquakes happen in Indonesia, near the Andaman and Nicobar Islands, and other places in Southeast Asia because these places are situated on major plate boundaries,” he added.
Kumar said there are minor plate boundaries too, having faults and fractures.
“Tuesday’s earthquake occurred in an unusual area. Earlier, a similar earthquake occurred 9-10 years ago in the Bay of Bengal region. That means there is a minor fault system under the sea. More studies are needed to know more about this,” he added.
Echoing similar thoughts, Prantik Mandal, chief scientist at CSIR-National Geophysical Research Institute (NGRI) Hyderabad said a detailed study on earthquakes occurring in the Bay of Bengal will reveal the causes.
“After the study of faults and fractures in the plates, we can assess the vulnerability of the region,” he added.
Tapas Kumar Biswal, a structural geologist and visiting professor at IIT Bhubaneswar, said preventive strategies to face potential future disasters is the need of the hour.
“This earthquake is unusual for the Odisha coast. Earthquakes usually occur in Japan, the Philippines, Myanmar, and Indonesia because these countries are located within the ‘Ring of Fire,’ a highly seismic zone around the Pacific Ocean where tectonic plates collide, causing frequent earthquakes and volcanic activity,” he said.
Biswal said the Bay of Bengal area is becoming unstable now. “Because the gigantic rocks under the sea have faults and fractures. We cannot take this lightly. It is time we seriously study and understand the faults and fractures in the minor plates in the earth’s crust under this sea,” he added.
Debasish Bhattacharya, deputy director general of GSI, said they will send a team from Kolkata and another team from Odisha to conduct a study in the coastal part of Odisha and West Bengal where the tremor was felt. “We are continuously conducting studies on earthquakes. We will study this earthquake too,” he added.
