GUWAHATI: Assam has been experiencing low to medium intensity earthquake almost daily since April this year leading to panic, fear and concern among people and experts in the seismically active region.
The State was jolted by a major earthquake on April 28 this year. The quake, measuring 6.4 on the Richter scale, occurred near Dhekiajuli in the Sonitpur district. Since then the State has been experiencing low to medium tremors every day.
"Following the April 28 earthquake, which was the largest felt in last 70 years, there were numerous aftershocks of smaller to medium magnitudes.
There were about 30 aftershocks immediately after within about 2-3 days of the mainshock. As per the current knowledge about seismotectonic activity, we may have aftershocks coming for months extending to about 3 to 4 months due to continuous readjustment of the tectonic plates after the rupture occurred during the mainshock," Jayanta Pathak, a faculty at Assam Engineering College told The Sentinel on Saturday.
He, however, said these aftershocks are not to be construed as foreshocks of a big earthquake in near future.
"We must understand that our region (North East) is situated in a highly seismically active zone. We should invest our effort in making the built environment safe for expected earthquakes in future - which cannot be predicted accurately in terms of the probable time of occurrence," Pathak said.
A seismologist working with the North East Institute of Science and Technology (NEIST), Jorhat while echoing with Jayanta Pathak said there have been around 60 tremors (till June 19, 2021) since April 28 earthquake. He said such aftershocks would continue for another four to five months.
"Even though it is always difficult to predict the exact timing of earthquake occurrence, the current study and research suggest that there is no possibility of a big earthquake in the next 4 to 5 years," the seismologist who does not want to be quoted on the ground of official protocols of NEIST, said.
The seismologist said the Northeast is situated in a seismic active zone as the region is the meeting point of three major tectonic plates – the Indian plate, the Eurasian Plate and the Burmese plate. He said the relative movement of these plates makes the area very vulnerable as far as the occurrence of earthquake is concerned.
"So, the earthquake occurrence in Assam and North East is inevitable, only the time of occurrence and its intensity is unpredictable," the seismologist said. He advised the people not to get panic and instead remain alert to face any eventuality.
According to the seismologist occurrence of earthquake is a mean of releasing stresses that are accumulated deep inside the earth because of the relative movement of the tectonic plates. Frequent occurrence of earthquake helps to release the accumulated stresses in phases that ultimately prevent the possible occurrence of an earthquake of a bigger scale, he said.
"Since the April 28 earthquake and aftershocks have been originated from the Sonitpur region, we should monitor the development properly. Our government agencies and other departments concerned should find out if it was an indication of a much bigger earthquake. There is already scientific research on the possibility of a bigger earthquake in future due to the Kapili fault zone. The Kopili fault zone is a 300-km-long and 50-km wide lineament (linear feature) extending from the western part of Manipur up to the tri-junction of Bhutan, Arunachal Pradesh and Assam," an expert at Gauhati University told this reporter.