Tuesday, September 20, 2011

Ministry seeks IIT-Kgp report on earthquake

Jhimli Mukherjee Pandey | Sep 20, 2011, 05.39AM IST

KOLKATA: The tremor that shook the north west of Sikkim, the spot where the earthquake occurred on Sunday, was strong enough to wipe out an entire valley (.45g), says a report of the geophysics department of IIT Kharagpur. The report was sought by the ministry of earth sciences as the department is its nodal agency as far as earthquake monitoring in Eastern India is concerned. The ministry has set up at least 16 earthquake monitoring laboratories in Sikkim and North Bengal, which are monitored by faculty and students of the institute.

At the spot where the earthquake had happened in the north west of Sikkim, the tremor shake up was as strong as .45g, enough to wipe out an entire valley, says a report of the geophysics department of IIT Kharagpur. The report was sought by the ministry of earth sciences as the department is its nodal agency as far as earthquake monitoring in Eastern India is concerned. The ministry has set up at least 16 earthquake monitoring laboratories in Sikkim and North Bengal, which are monitored by faculty and students of the institute.

The data that was recorded in these laboratories at the time of the earthquake shows the range of ground acceleration that spread from the epicentre to different parts of Sikkim, Bengal, Bihar and Bhutan.

The data recorded in these laboratories has been able to pinpoint that the epicentre lay 35 kilometres beneath the earth's surface and the quake could be categorized as one of

the strike-slip movement type that came with a single big jerk and three smaller aftershocks. The ground just above the epicentre felt a jerk of .45g. The report says that Gezing, another place in Sikkim, felt a tremor of the magnitude of .3g, Lingja followed next with .28g and Mangan .24g.

"The epicentre of the tremor lies just below the Kanchenjungha liniament or hidden fault, making it extremely earthquake prone," said Shankar Nath, head of the geophysics department who is also the lead scientist of the project.

There are five research scholars of the institute with him who have analysed the data of the earthquake. with him.

The report states the intensity of the tremor felt at different places. According to the report, the tremor in Darjeeling was very high in intensity.

According to the report the ground accelaration at Singtam and Gangtok in Sikkim were, .23g and .21g respectively. The tremor was very high in Darjeeling where the intensity was .27g whereas it was .22g in Siliguri.

"Though in Kolkata the tremor was very

felt at least thrice, the intensity was very low at .085g, so you can understand from our data how strongly the ground was shaken up in Sikkim!" said Manik Das Adhikary, a seismologist at the institute.

"Sikkim is highly earthquake prone and hence the ministry has been monitoring the situation there through us. It is a coincidence that we had just suggested to the ministry that Sikkim should be upgraded to zone 5 in the seismic map of the country considering its susceptibility to quakes," Nath added.

Source: http://timesofindia.indiatimes.com/city/kolkata-/Ministry-seeks-IIT-Kgp-report-on-earthquake/articleshow/10048144.cms