Hyderabad: Telangana, which is largely considered safe from major seismic activity as it lies predominantly in Zone 2 on the seismic map, witnessed a rare incident 5.3 magnitude earthquake on December 4th. The quake struck Mulugu district with its epicenter near Medaram, which is part of the district Godavari Rift Zone classified as Zone 3.
According to seismologists, the Godavari rift zone is prone to moderate earthquakes. The latest quake was caused by the release of strain energy along the fault system at a depth of 40 kilometers. “The current earthquake is occurring in seismic zone 3 of the Godavari Trench. The entire state of Telangana, except this part, lies in Zone 2, a safe seismic zone,” said Prakash Kumar, director, CSIR-NGRI.
In the last six decades, Telangana recorded four significant earthquakes: a magnitude 5.3 earthquake in Bhadrachalam in June 1969, a magnitude 4.5 earthquake in Medchal in 1983, a magnitude 4.8 quake near Pulichintala in January 2021 and the quake on Wednesday in Medaram.
Prakash Kumar said: “We cannot predict whether there will be more earthquakes in the region, but we are sending strong motion accelerometers to Mulugu to record aftershocks. Instruments are being set up to monitor micro-earthquakes in the region.”
He mentioned that the tremors were recorded by eight instruments in Mulugu as well as at observatories in Choutuppal and NGRI campus in Hyderabad.
Sri Nagesh, former chief seismologist of NGRI and faculty member at IIT Madras, said the region is prone to moderate magnitude earthquakes. “We saw a similar quake in 1969 and since then there have been smaller quakes between Medaram and other areas,” he said.
Refuting speculations, Nagesh said, “This earthquake is tectonic in nature and has nothing to do with the Kaleshwaram irrigation project.” Nagesh also said that aftershocks were likely, recalling how Bhadrachalam experienced aftershocks for a decade after the 1969 quake.
Seismologists emphasized the importance of earthquake-resistant structures in the region. “Authorities should promote earthquake-resistant construction methods and protocols. It is crucial to ensure resilience of buildings based on the seismic requirements of the area,” said Prakash Kumar.