21 seismological observatories of NCS functioning in NE India, Read details here
Guwahati: At present 21 seismological observatories of the National Center for Seismology (NCS) are functioning in the Northeast India whose data along with the remaining observatories have been used for locating the earthquake.
Northeast India falls in seismic zone V in seismic zoning map of India (IS 1893 (Part 1): 2016) which is the highest seismically active zone.
On Wednesday, a perceptible earthquake of magnitude 5.2 occurred in the Northeast region of India at Goalpara district, Assam at 26.15 N and 90.28 E with focal depth 14 km near Lakhipur sub-division of Goalpara district at around 8.45 am in the morning.
The epicentre is about 141 km west of Guwahati.
The earthquake occurred around 20km at the western side of North-South trending Dhubri fault of Assam. The high seismicity of the northeast Indian region has been attributed to a complex tectonic province displaying juxtaposition of the E-W trending Himalaya and the N-S trending Arakan Yoma belt. The major tectonic background includes the eastern Himalayan structures, the Mishmi Massif, the Indo-Myanmar arc, the Brahmaputra valley, and the Shillong plateau. The Himalayan structures mainly consist of the thrust planes namely the Main Central Thrust (MCT), Main Boundary thrust (MBT), Main Frontal Thrust (MFT) and their subsidiaries.
Interestingly, the occurance of Goalpara earthquake (5.2) is found located at distance of about 250 km in the south west of the April 28, 2021, Sonitpur earthquake (6.4) that rocked at 17 km depth, which signifies two different source ruptures associated with varying amount of structural heterogeneities.
The list of past earthquake events of Magnitude 5.0 and above occurred within the 200 km of radius from today’s epicentre during the last 20 years is as follows: