The Hindu Business Line : When Mother Earth trembles, NGRI is galvanised

THE devastating earthquake that wreaked havoc in Pakistan and parts of Jammu and Kashmir in India on October 8, has revived the long-held view of earth scientists that a great earthquake is due in the Himalayan region.

The earthquake of 7.6 magnitude with its epicentre close to Muzzafarabad in Pakistan, is perceived by this group of seismologists, as a comparatively small, expected event in the Himalayan belt. The massive amount of stress that is locked up in the depths of the region extending about 2,400 km has to be released, and it shall be in the form of a massive earthquake measuring above a magnitude eight on the Richter Scale.

The Himalayan region is one of the most active and high-risk areas for earthquakes. The last great earthquake to hit the region was in Assam (1950), with magnitude of 8.6.

Prior to that the magnitude eight plus earthquakes, include Shillong (1897), Kangra (1905) and the Bihar-Nepal (1934). After 1950, there is a period of lull.

Interestingly, seismologists also theorise that the silent period in the Himalayas has been contrasted with an active phase in Peninsular India. In the last 50 years, this region has seen the big Koyna earthquake of 1967; Latur (1993); Jabalpur (1995) and Bhuj (2001).

The Union Department of Science and Technology (DST) has been making efforts to strengthen and upgrade seismological network to enable monitoring and provide a reliable estimate of earthquake parameters and its effect. It has also budgeted Rs 50 crore over five years.

The India Meteorological Department (IMD) has been among the oldest institutes with a network of seismological observatories and earthquake scientists, which has been studying earthquake activity in the country. The Wadia Institute of Himalayan Geology, the Earthquake Engineering Centre of the National Institute of Technology, (NIT), Roorkee and a couple of other centres also have established strengths in seismology.

The Hyderabad-based, National Geophysical Research Institute (NGRI), established in the early 1960s, is another major centre for studying these natural phenomenon.

Dr V.P. Dimri, Director of NGRI, said constantly monitoring of the local seismic activity has become critical in understanding bigger quakes. Currently, a satisfactory network in the Himalayan region is lacking and hence there is greater need for a network. The NGRI has plans to put broadband stations in the Central Himalayan region and the North-East. These would be connected to the Central Observatory. Simultaneously, to strengthen the network in the Koyna region, which is experiencing heightened seismic activity, the NGRI set up 10 stations. These are to be linked through a VSAT to the NGRI observatory in the next four months, Dr Dimri said.

Post December 26, 2004 tsunami triggered by the massive earthquake of Sumatra islands in Indonesia, the Centre had taken a decision to link 16 of the 58 observatories of the IMD and the NGRI , which are located in different geographical locations. The idea is to help in quick estimation of the earthquake magnitude, which, in turn, would help in detecting a possible tsunami and alerting people.

Over the years, the institute has made several contributions in the areas of Reservoir Induced Seismicity, like the possibility of the Koyna dam triggering the earthquake to the fears over the Tehri Dam. Similarly, scientists have demarcated fault zones criss-crossing certain regions of the country and hence posing risks for earthquakes.

The NGRI has also brought out an earthquake hazard map of India, clearly identifying regions and the scales of risk they run.

The NGRI has emerged as a centre with expertise in different geophysical areas. Mineral exploration, groundwater resource studies, oil and gas hydrate surveys, Antarctica studies, geochemistry and geo-environmental studies.

In addition to its research contributions, the institute has done exceedingly well in applied work, especially supporting the oil industry in recent years. Its earnings from external sources were Rs 19.19 crore during 2004-05, the second highest among the chain of 38 CSIR labs. It is expected to touch Rs 25 crore by this fiscal end, which would be in excess of the annual budgetary support of Rs 22 crore from the CSIR.

The institute has a high score on the science citation index publications and is obtaining patents, Dr Dimri said.

The institute is able to plough back the earning from industry productively into building new infrastructure and human resources. It has recruited 30 research fellows, which it supports from these funds. With the demand for oil and alternate sources of energy as well as for minerals rising, the NGRI is positioned to play an important role. It has to concentrate on raising a larger number of young researchers and forge closer liaison with the Indian industry.

Earthquake study: Earthquake studies in NGRI literally started off with a big bang. A major earthquake in Koyna rattled the seismological observatory in its Hyderabad campus into action on December 10, 1967.

The NGRI was planning to inaugurate the then modern observatory to monitor earthquakes on January 1, 1968. But the 6.1 magnitude (Richter Scale) earthquake that struck Koyna and surrounding regions of Maharastra, hastened its operation by registering the first major recording.

The Koyna earthquake, also set off a major debate on the role of big dams in triggering large earthquakes in the country and around the globe. In the years gone by, NGRI has emerged as one of the premier facilities in the country to monitor, study and find ways of better understanding and thereby build a possible early warning system.

Today, the NGRI observatory has the capability to record earthquakes of magnitudes 4.5 and above with epicentres anywhere in the world instantly. It has been upgraded several times, with the addition of latest equipment, said Dr Dimri.

Article E-Mail :: Comment :: Syndication :: Printer Friendly Page