Kolkata : A chain of tremors felt across east and north India on Tuesday was due to the ongoing adjustment or “relaxation process” in the Himalayan belt in the aftermath of the massive April 25 earthquake that hit Nepal, experts said on Tuesday.
A quake in Afghanistan on Tuesday morning also added to the aftershocks.
“The aftershocks felt across India are linked to the April 25th Nepal quake. These will carry on for a long time until the energy that was released in the temblor is dissipated.
“The region is undergoing relaxation and an adjustment process is on post the last quake. This is not a major new quake,” A.P. Singh, scientist at the Gandhinagar-based Institute of Seismological Research (ISR), told IANS.
As an example, he cited the devastating Bhuj earthquake in Gujarat in 2011 that claimed around 20,000 lives.
“Even 13 years after the Bhuj quake, aftershocks continue due to the energy dissipation and relaxation,” the seismologist said.
However, this doesn’t put India “not in danger” of a major new quake since the epicentre of the current one is 18 km east of Kathmandu, according to Singh.
The death toll due to the April 25 killer quake in the Himalayan nation, measuring 7.9 on the Richter Scale, has crossed 8,000.
While the country was barely recovering from the loss, a temblor measuring 7.3 on the Richter scale hit Nepal on Tuesday, with its epicentre not far from Mount Everest — the world’s highest peak at 8,848 metres.
Indian states of West Bengal, Bihar, Odisha, Jharkhand and capital New Delhi as well as other areas were rocked by the tremors. Tall buildings also shook in faraway Kochi in Kerala.
Devendra Pradhan, deputy director general of Meteorology (Eastern region), Regional Meteorological Centre, Kolkata, said there were two additional aftershocks in India, measuring 6.2 and 5.4 on the Richter scale, and clarified that weather phenomena like rain and winds are not associated with earthquakes.
The series of disasters have drawn attention to the vulnerabilities of the Himalayan region, a complex domain.
The 2,500 km-long Himalayan arc extending from Kashmir in the northwest to Arunachal Pradesh in the northeast, is seismically “very active” said IIT, Kharagpur professor, Sankar Kumar Nath.
“On top of that, the entire belt was disturbed in the April 25 quake. There were about nine aftershocks in the weeks that followed. While one measured 6.3 on the Richter Scale, the others were between 5 and 5.6. This will go on, maybe for several months or more,” Nath told IANS.
In addition, he said, a quake measuring 6.9 on the Richter scale struck Afghanistan on Tuesday morning, which also affected India.
“Afghanistan lies in the Eurasian plate and the Indian plates are continuously colliding with the Eurasian plates. What India experienced today (Tuesday) was due to the Afghanistan one coupled with the Nepal quake aftershock,” Nath, professor of the institute’s geology and geophysics department, said.