Suitability of Widely Followed Earthquake Early Warning Systems to Seismically Active Regions of India, by Considering Destructive Intensity as a Parameter

Background: Indian subcontinent has been witnessing moderate to damaging earthquakes (EQs) since prehistoric times. With growth in the population density and the construction activity, the probable damage during future EQs will also be manifold in comparison to the past. Issuing warnings in advance to the actual arrival of damage causing secondary waves under Earthquake Early Warning (EEW) system is widely followed in different parts of the globe. Though India has been facing EQ induced damages on an alarming level, no functioning EEW system is available in the Indian subcontinent. Present work tests the effectiveness of widely followed Compact Urgent Earthquake Detection and Alarm System (UrEDAS) of Japan by using Destructive Intensity (DI) as a parameter. Main findings: To do so, firstly based on PEER records, empirical correlation between magnitude and intensity is proposed for the detection of alarming EQ. Further, proposed correlation is applied to three different sources of ground motion dataset namely K-NET, PEER and PESMOS in order find out to whether the ground motion is corresponding to a damaging EQ, based on P wave arrival and subsequently use the information to issue a warning in advance. In the absence of recorded ground motion for major to great EQs in India, synthetic ground motions developed in earlier work are used for identification of damaging EQs and issuing of alarm. Conclusions: Overall, it is found that out of 149 EQ records (M ≥ 5) considered in this work, 139 EQs are found correct to raise warning, based on the proposed methodology. In addition, the time window of escape between issue of warning and the actual arrival of secondary waves, are found to vary from 0s to 1mins approximately. Findings from present work concludes that identification of damaging EQ based on first 3s P wave signature, as followed in US and Japan are also compatible for Indian subcontinent towards development of a EEW for the country. This will be very helpful in minimizing casualties and building damages during probable future EQs in India.