Mild tremors were felt across Satara, Kolhapur, Mumbai, Pune, Ratnagiri and Navi Mumbai early on Saturday after two low-intensity earthquakes of 4.9 and 4.0 magnitude took place in Satara and Ratnagiri districts respectively.
According to the India Meteorological Department (IMD), the first earthquake took place at 10.57 a.m. and the second one at 11.47 a.m. The government website rated the intensity as “slight.”
Earlier in the day, an earthquake of 4.0 magnitude, with its epicentre in the Rann of Kutch in Gujarat, was reported at around 9 a.m. It is not clear if its effects were felt in Maharashtra.
No damage to human life or property has been reported, State government officials said. “The walls of a few mud houses in Konkan [coastal Maharashtra] area developed minor cracks. But no damage has been reported,” an official of the State Disaster Management control room (DMCR) told The Hindu .
The Nuclear Power Corporation of India Limited (NPCIL) too issued a press release stating that the quake did not impact any reactors.
“Two earthquakes of mild intensity have been reported… No effect was felt at any of the nuclear power plants, and all the reactors continue to operate normally,” the release stated.
The epicentre of the first quake was at Goshatwadi in Patan taluka, Satara district, around 10.4 km from the Koyna dam, an official at the State DMCR said. He said there was no damage to the dam. “The aftershocks were felt at the same place,” he said.
Asked about the second low-intensity earthquake listed on the IMD website, he said it might not be another earthquake, but the aftershocks of the previous one. The website has stated that a 4.0 magnitude quake [slight intensity] was recorded near Ratnagiri at 11.47 a.m.
Experts have said the second earthquake mentioned on the IMD website was a separate one and not an aftershock of the first one.
“According to Ravi Sinha, an expert seismologist and IIT-Bombay professor, the two earthquakes can be called independent events. Aftershock is only when a big earthquake of 6.0 magnitude is followed by shocks later. In this case, the two earthquakes are of smaller magnitudes,” S.C. Mohanty, Director of Disaster Management, told The Hindu .
The IMD website gives the depth of both the earthquakes as 10 km.