Tremors, tsunamis: Let’s stay prepared
The powerful earthquake that struck off the coast of the Indonesian island of Sumatra on Wednesday caused panic as far west as the eastern coast of India, but is not known to have caused any serious damage. This is plain lucky. With the temblor recording 8.6 on the Richter scale, its potential for harm was immense. The fact that its epicentre was a few hundred kilometres into the sea, and away from inhabited areas, may have prevented a disaster of serious magnitude. But this was not the only bit of luck.
Experts suggest that the earth’s plate in the sea moved laterally. This caused tremors to spread horizontally through the waves, impacting coastal habitations in several countries to some degree. But a tsunami did not occur. That would have happened if the plates in the earth’s crust had been displaced vertically. With memories of the terrible 2004 tsunami fresh in the minds of people across Asia where about two lakh people perished, many braced themselves for the worst. Fortunately, the worst imaginable scenario did not come to pass. This, of course, did not stop scare- mongers, who oppose nuclear power generation, from questioning the basis of the Koodankulam atomic power project once again, although it is well known that even the kind of tsunami that hit Japan in 2011 cannot impact Koodankulam as the plant in Tamil Nadu is several generations ahead of the one in Fukushima in its safety aspects.
None of this means that we should lower our guard either against a tsunami or a major earthquake. Fortunately, a tsunami can be predicted. Modern equipment can give an hour’s advance warning approximately. If in India we have systems in place and we know what to do, lives can be saved when the big waves strike the coastal areas. But earthquakes cannot be predicted. This means that in zones that can be struck by highintensity quakes, the authorities must insist on the use of the appropriate type of building materials, as they do in Japan. It is a well- known saying that an earthquake does not kill, but raining bricks and mortar do. In India, people are mostly unaware of these matters and have to be educated about it. This is because a large part of the country — especially northern India — is in a high seismic zone. Those who study these matters tell us that a major earthquake may be expected in India every 55 years on average, and one may just be around the corner. While quakes cannot be predicted, preventive action includes decongestion in urban areas, especially major cities. This would call for a horizontal spread of urban agglomerations, not vertical, as seems to be the case at present.