BIG TERMORS
Between 1990 and 2006, more than 23,000 lives were lost due to 6 major earthquakes in India, which also caused enormous damage to property and public infrastructure
Uttarkashi, 1991: 768 killed, 90,000 houses damaged
Latur, 1993: 7,601 people killed
Jabalpur, 1997: 39 killed
Bhuj, 2001: 12,000 killed and 90 per cent of homes destroyed
J&K, 2005: 20,000 killed on the Pakistan side and about 1,000 on the Indian side

DANGER ZONES
The whole of the Northeast, the Himalayas, Kutch and parts of the region near the Aravallis fall in high-risk zones. 59 per cent of India’s land area could face moderate to severe quakes

As another earthquake hit the country last week, this time in Delhi and adjoining areas, the need for an effective quake forecast system has once again come under focus.

Scientists have been trying for years to develop a model, which would be able to predict earthquakes well in advance. While there has been considerable success in mapping places that are prone to earthquakes, hardly anything is known about the timing and intensity of the quakes.

Scientists say there is a need to build a model for forecasting earthquakes. Key to developing any such model is the study of ‘precursors’ or the symptoms that precede an earthquake.

It has been observed that there are changes in a number of physical and electrical properties of the earth’s surface—like increase in seismic activity, radon gas emission, change in ground level or ground-water levels, electrical conductivity—before an earthquake. For example, post-quake studies have revealed that the earth’s temperature had been rising steadily in Bhuj since January 21, 2001, five days before the devastating quake in Kutch in Gujarat that killed more than 12,000 people.

... contd.