'India a laboratory for seismologists'

India is no stranger to earthquakes. In recent memory, Latur and Bhuj districts in Maharashtra and Gujarat witnessed devastating tremors in 2003 and 2001 respectively. Such quakes leave clues that can aid preparations for future events, say seismologists KUSALA RAJENDRAN, professor, Indian Institute of Science, and CP RAJENDRAN, adjunct professor, National Institute of Advanced Studies. The Rumbling Earth-The Story of Indian Earthquakes, captures their work on historical as well as recent quakes. In an interview with ROHINI KRISHNAMURTHY, they discuss the science of earthquakes, why the Himalayas are due for a huge event and why prediction remains a challenge. Excerpts:

- ROHINI KRISHNAMURTHY

Your book aims to introduce your work on earthquakes for a general audience. Why did you feel this was needed?

Kusala Rajendran: Every time we have an earthquake, I have noticed that most journalists who try to report on the event struggle because they are unaware of the basic things about earthquakes. I have also seen the public interest in learning about earthquakes. When people ask me what I am working on and I say earthquakes, I usually end up giving them a mini-lecture on plate tectonics [a scientific theory explaining the movement of the earth's upper plate, which is about 100 km thick and is broken up into separate tectonic plates].

People also ask us why earthquakes occur in some places and not others; and whether it will happen near their hometown. When we see so much curiosity, communicating is important. There is also a lot of academic interest in why earthquakes occur. Given our long experience of working on Indian earthquakes, we also had a lot of human-interest stories that we thought should be shared.

India is like a laboratory for seismologists because we have the Himalayas and the Andaman and Nicobar Islands, areas with active subduction zones where tectonic plates collide and thrust beneath each other. Though rare, damaging earthquakes do occur within the plate interior, like in Latur. We also have one of the largest and most spectacular examples of reservoir-induced earthquakes in Koyna, Maharashtra. We already had the material and experiences to put the book together.

C P Rajendran: Our work in paleoseismology was also the beginning of a new line of research in India. Thus the book also partly became a biographical sketch for the two of us.

How did you begin your work in paleoseismology?