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Time to get cracking

Time to get cracking A year has passed. But Gujarat remains shaky in more ways than one. Metaphorically, its residents are struggling to come to grips with the devastation caused by the January 26, 2001, earthquake. In a literal sense, too, the ground beneath their feet is anything but terra firma.

Sample this. Junagarh district in the state has experienced 1000 tremors in November 2001 itself. And these may not be just aftershocks. A peek into the past suggests that the quivers could well be a precursor to another impending catastrophe (such tremors in Bhavnagar preceded the Bhuj earthquake. Heightened seismic activity also took place before the Latur and Jabalpur quakes).

That these moderate intensity tremors have occurred in other areas of the country is also a matter of great concern. In recent times, quakes have rocked regions such as south India that are scientifically designated as less seismic zones. At the same time, the seismically active Himalayan belt has regularly experienced earthquakes of a higher magnitude. In the year 2000, out of 17 earthquakes measuring more than 5.5 on the Richter scale, seven have occurred in south India. In 2001, 12 out of 20 quakes of a magnitude higher than 6 have been reported in southern India. Top seismologists have warned of major earthquakes in both the northern and southern areas.

"Seismic activity in southern India is much more than that in Latur and Uttarkashi (two quake-prone areas),' says H N Singh, a scientist with the Thiruvananthapuram-based Centre for Earth Science Studies (cess). Karnataka's Kolar gold fields experienced around 15 mild earthquakes in just two days in November 2001, causing widespread panic. The apprehension may not be misplaced because the township is placed over the world's deepest mines and also on an active seismic area called the Mysore North fault line.

The churning inside the Earth has led the union government to designate 57 per cent of the country's area as more or less quake prone, raising the number of such hot spots by three per cent. India is divided into regions falling in any seismic zone, ranging from 1 to 5 in the ascending order of severity of the tremor (see map: Seismic hot spots). Despite acknowledging the threat potential, the administration is hardly geared up to mitigate it. Feeble follow-up
If one needs a disaster to understand it better, the Gujarat earthquake afforded experts a huge opportunity. But the tragedy that claimed more than 30,000 lives and damaged property worth us $10 billion has evoked nothing more than a lukewarm response from officials (see box: Rising from the rubble). Not surprisingly, the calamitous incident has generated a debate about the scientific community's ability to comprehend the complex phenomenon. "The earthquake has shaken the nation, but the system is not responding with alacrity,' says D K Paul, head of the Roorkee Engineering College's earthquake engineering department.

S S Merh, a senior geologist and retired professor of Maharaja Sayajirao University, Vadodara, says: "Quakes in the Kutch region have never been taken seriously. Even though parts of Gujarat fall in as vulnerable a seismic zone as the Himalayas, not much has been done to chronicle the risk.'

Significantly, various regions of the state fall in the highly seismic zones, 3, 4 and 5. Before the Republic Day tragedy, the last major earthquake occurred in 1956 but it had done little damage to the urban areas of the state.

Primed reaction
Not long ago it was believed that earthquakes come like a bolt from the blue, catching people unawares and causing great damage. With their ear to the ground, seismologists in countries such as Japan, China, Russia and the us have devised a method that not only enhances their preparedness, it actually enables them to partially forecast a quake. Micro zoning

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