Saturday, January 15 2005 17:50 Hrs (IST) - World Time -

Port Blair: Preliminary survey data today (Jan 15, 2005) confirmed that the area around Andaman and Nicobar capital Port Blair had shifted by over one metre in the south-eastern direction after the killer earthquake and tsunami of December 26, indicating that new maps would be required for the archipelago now.

A team of surveyors from the Survey of India compiling scientific readings from across the Andaman and Nicobar Islands, has discovered that their Port Blair control point had shifted towards the south-eastern side by 1.15 metre from its earlier position.

"The sea has also recorded a not-so-significant drop of 25 cm from its earlier level at the Port Blair control point which leads us to infer that there could be some subsidence also," Surveyor General of India Prithvis Nag told reporters.

However, the mean sea level has also increased by 1.5 m post-tsunami, he said.

A seven-member team of the survey body studying the latitude, longitude and height at 20 of its control points in all islands would compile the final data to be released at an international conference on disaster management on January 21, he said.

"The longitude and latitude of these islands will have to be redefined after the final data emerges and after studying the surface topography we will indicate the need for new maps for the Andaman and Nicobar islands," he said.

Pointing out that the detailed survey will have to be carried out for over two months now, he said this preliminary data will be matched with the fortnightly data released by the International Geodetic Station (IGS), which tracks the precise movement of the earth surface.

"This synchronisation will confirm any tilt or shift and the need for new mapping requirement," he said.

Nag said the shift in landmass could have implications in movement of ships and aircraft, which might need adjustment, in large civil construction works that require precision data as well as strategic data that uses the Global Position System

The team would voyage to distant islands as also fly in naval helicopters to gather more data over the next few days, Nag said.

"We will also have to replace five of our control points including those in the Car Nicobar and Indira Point areas, which have been damaged by the tsunami. This is also posing a slight logistic problem as the communication channels have gone haywire in the disaster," he said.