Panaji, April 29 :    Panaji, April 29:  Oceanographers here have announced that they have made preliminary underwater archaeological exploration of what is believed to be a sunken city off Mahabalipuram. The formal announcement has excited the international media, with a section of the press labelling the exploration an attempt to find 'India's Atlantis'. It is believed that a great flood swallowed a city along the eastern coast some 1,500 years ago because the 'gods grew jealous'. The Goa-based National Institute of Oceanography said its team of 'underwater archaeologists' along with the Scientific Exploration Society of the UK had 'unearthed' evidence of submerged structures off Mahabalipuram earlier this month. 'There is a popular local belief that the Shore temple of Mahabalipuram is the last of a series of seven temples, six of which have been submerged,' the institute's spokesman, S.R. Bhat, said. During the exploration, underwater investigation was carried out at five locations in 5m to 8m of water depths, 500m to 700m off the Shore temple. 'Investigations at each location have shown the presence of stone masonry, remains of walls, a big square of rock-cut remains, scattered square and rectangular stone blocks and a big platform with steps leading to it. All this amid the geological formations of rocks that occur locally,' the spokesman said. But most of the structures are badly damaged and scattered over a vast area, with centuries of biological growth of barnacles, mussels and other sedentary organisms. It was found that the area covered by the construction was 100m by 50m. But scientists feel that the actual area covered by the ruins 'may be much larger'. 'The possible date of the ruins may be 1,500 to 1,200 years Before the Present. The Pallava dynasty, which ruled the area during the period, had constructed many such rock-cut and structural temples in Mahabalipuram and Kanchipuram,' the scientists said. The other questions that arise are what structures did exist and the cause of their submergence. British newspapers recently reported that photographs of what appear to be submerged ruins off the coastal town of Mahabalipuram in the Bay of Bengal corroborated the long-held myth. The pictures were taken by divers led by a former Royal Marines officer, Monty Hall. Mahabalipuram is full of stone-carved temples. It was the chief port of the Pallavas, who ruled over much of southern India from the first century Before the Current Era to the eighth century AD. British media reports said the location of the ruins was pinpointed by Graham Hancock, the best-selling author of The Sign and The Seal, who has studied the myths of the region as well as of similar lost cities in the Mediterranean. 'Mr Hancock believes cities such as Mahabalipuram were destroyed when waters rose at the end of the last Ice Age between 17,000 and 7,000 years ago, swallowing up about 25 million sq kilometres of formerly habitable lands,' said a report in London's The Independent.