India steps up work on quake warning system

India is stepping up its research capabilities to pick up early signals of an impending earthquake by setting up a network of observatories to study the intricate processes that take place in seismically active zones.

A string of observatories are already in place at Ghuttu in Himachal Pradesh, Shillong in Meghalaya, Koyna in Maharashtra, and Port Blair in Andaman and Nicobar to monitor various earthquake precursory phenomena.

"We have plans to increase the number of observatories," R S Dattatrayan, head of seismology wing of the India Meteorological Department told reporters in New Delhi.

He said observatories look for changes in seismicity patterns, gravity anomalies, electrical resistivity changes, electromagnetic perturbations, water level changes, geo-hydrochemical changes, radon and helium anomalies and thermal anomalies.

"Preliminary analyses of these data sets have provided useful leads on the ongoing tectonic processes in the Koyna-Warna region," he said.

However, seismologists require data for at least 10 years from such observatories to see how the changes take place and their relation with an earthquake event.

"We need to establish a connectivity between an event and changes in the parameters," Dattatrayan said.

IMD currently has a network of over 55 earthquake monitoring stations. In addition, it has 17 real time monitoring stations in seismically prone areas which are linked to a high-speed network.