As many as 178 mild tremors have been reported in Kerala in the last 10 years.
These tremors of mild or medium intensity did not cause any extensive damage but the government had strengthened the preparedness to meet any eventuality arising from natural calamities as part of its disaster management plan, a reply furnished by chief minister Oommen Chandy in the assembly on Monday said.
Of these tremors, the one that was felt in the south-west areas of Kochi on July 25, 2005, had the highest intensity of 3.7 on the Richter scale, he said.
Besides the Indian Meteorological Department, the Centre for Earth Science Studies (CESS) and Kerala State Electricity Board (KSEB) had their seismographs installed in various parts of the state.
Some of these were digitised broadband systems which could record and measure the quakes accurately.
Six more sophisticated seismographs would be installed in parts of Idukki district, where most of Kerala's dams and reservoirs, including the 116-year-old Mullaperiyar dam, are located.