Since the devastating earthquake hit Gujarat and other parts of the country on the morning of January 26, Dr S K Srivastav, additional director general of the Indian Meteorological Department, and his colleagues have scarcely rested.

They have been on their toes, keeping a close watch on the developments -- taking readings from instruments round the clock and issuing warnings to the public accordingly.

In an exclusive interview to Special Correspondent Onkar Singh, he defended the IMD's reading and refutes the allegation made by another eminent scientist that the IMD had played down the intensity of the earthquake.

Dr Harsh Gupta, director of the National Geographical Research Institute, has claimed that the earthquake measured 7.9 and not 6.9 on the Richter Scale as claimed by the IMD.

Dr Gupta is an eminent seismologist. He should have checked his facts before rushing to the media and making a statement. In fact, he wrote us a letter in which he said the reading taken by the IMD was correct.

We have also taken the surface wave magnitude reading. But this reading is not reported to the people. Both readings are correct. But when we tell the media about the magnitude of the earthquake we refer to it in terms of the Richter Scale only.

Why then is there a controversy about different intensities of the same earthquake by different observatories?

I have explained to the media time and again that the accurate reading of an earthquake is recorded by the meteorological department of the country where it occurs because that reading is based on body wave magnitude. While the observatories in other countries record what is known as surface wave magnitude.

Therefore, our reading that the earthquake was of the intensity of 6.9 on the Richter Scale is correct. The readings issued by US-based observatories have not been recorded by them as 7.9 on the Richter Scale.

While refusing to spell out the number of possible deaths, you said the other day that your worst fears could come true. Now that the figure has crossed over 20,000 deaths, what are your worst fears? Where would you place the death toll? Will it cross 50,000?

I would go by the official figures because that is authentic. I would not like to speculate on the death toll. Yes, the devastation is beyond our comprehension. Villages and towns have collapsed. The figure could rise further as we fish out bodies from the debris.

The figure given by the official sources so far is only a tentative figure. The real picture would emerge once all the debris has been cleared and the rescue operations are over.

Bhuj and Morvi towns have been totally devastated. Even the towns and villages around them have been razed to the ground. Surat, which was far away from the epicentre, has also been hit badly.

This is a real disaster that I have witnessed during my age. It is really horrible. The death toll could be very high because the population density was very high. More then 3 million people have been affected. Let us first rescue the people. Statistics should come later.

Bangalore was known to be safe, but even it was hit by an earthquake of the intensity of 4.5 of the Richter Scale. How do you explain this?

Latur was located in what we call safe Zone II. But that myth was broke when Latur was hit by the earthquake that took more than 7,000 lives. Earlier we used to call Zone II a safe zone, but it is no longer the case now.

The earthquake in Bangalore surprised us the most. Now it is more than confirmed that even the southern peninsula is not safe either. So we would have to reassess our zoning system.

We have recently fitted our observatories with the latest equipment to monitor tremors. We would have to put more observatories in that region and also equip them with micro-earthquake systems so that we could monitor the new faults that might occur in that region.

Why have there been so many aftershocks in Bhuj and surrounding areas? More than 200 aftershocks in a matter of three or four days...

I think your figure in on the lower side. We have so far recorded more than 500 aftershocks in Bhuj and other parts of Gujarat. But we do not bother so much about the tremors of less than three in intensity. But if you talk of 3 and more then we have recorded 92 medium and major shocks. The big one recorded on 29.1.2001 was of the intensity of 4.5 on the Richter Scale.

Such an aftershock definitely causes concern because it has the capacity of doing further damage to already damaged structures.

We expect that this kind of seismic activity will continue for some more time. So I would appeal to people in the earthquake affected areas to stay away from damaged structures so that if an already damaged structure does fall, no human life is lost.

Do you rule out the chance of a major aftershock?

I cannot predict what will happen in the near future, but the possibility of a major aftershock can definitely not be ruled out. We do not want a repeat of Latur when more people lost their lives in the aftershocks than in the original tremor.

Is the Gujarat administration keeping a tab on the latest developments?

Chief Minister Keshubhai Patel has been in constant touch with us. I persuaded him to make an appeal to the people over All India Radio and television. I am happy he heeded our advice and appealed to the people of his state accordingly and asked them to stay away from damaged houses for the next few days.

Is it true that Delhi could be hit by an earthquake of the intensity of 7 and above?

Delhi comes in Zone IV and there is a strong possibility that the capital might be hit by an earthquake of the magnitude of 7 or 8 on the Richter Scale.

Delhi has a few fault zones in Muradabad, Sohna and the ridge in the heart of the city. I shudder to think of such a possibility because of the devastation it would unleash on the city. Most houses have not been built to make them quake resistant.

Design: Dominic Xavier

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