The tremor-prone Idukki district woke up to the latest rumbles early on Friday morning with the strongest registering an intensity of 3.1 on the Richter scale.
India Meteorological Department (IMD) located the depth of the same at five km below the surface and close to the Idukki dam, housing the largest hydro-electric project in the State.
According to the preliminary coordinates based on epicentral data given out by the Pune-based Amateur Seismic Centre (www.asc-india.org), the epicentre was 5.7 km to the west-southwest of Kallar; 15.9 km southeast of Idukki; 20 km northwest of Gudalur (Tamil Nadu); 30 km north of the Mullaperiyar dam; 36.5 km east-northeast of Erattupetta; 41.8 km south of the Anamudi peak; 67 km east-northeast of Kottayam; and 145 km north of Thiruvananthapuram.
Tremors were felt across the high-ranges at Idukki, Kumali, Kulamavu, Moolamattom, Mullaperiyar, Pashupara, Vagamon, Vandiperiyar, Topramkudi and Upputhara in Idukki district.
They were also felt at Erattupetta . Many people were woken up by this tremor at 5:45 a.m., which was actually preceded by a M2.8 foreshock at 5:37 a.m., the ASC said.