Laser scanning used to help preserve ancient rock carvings

PUBLISHED : Wednesday, 26 December, 2007, 12:00am
UPDATED : Wednesday, 26 December, 2007, 12:00am

Ancient rock carvings in Hong Kong - under threat from gradual erosion and bacteria - will be laser-scanned to keep track of their condition.

The design of the protective glass frames for the carvings would also be changed to make them more visitor-friendly, said Chan Shing-wai, chief curator for conservation at the Leisure and Cultural Services Department.

Eight rock carvings, believed to be between 3,000 and 4,000 years old, have been identified at Big Wave Bay and Wong Chuk Hang on Hong Kong Island, in Sai Kung, and on Cheung Chau, Tung Lung, Lantau and Po Toi islands.

Mr Chan said laser-scanning technology would be useful in compiling information about the carvings in a three-dimensional format. This would enable records to be kept of how the carvings are being affected by erosion and bacteria, he said.

'In the past, we determined the condition of the carvings using photographs, but it is not always accurate,' he said. 'But laser scanning allows us to compare the minimal changes occurring to the carvings over time.'

The design of protective glass covers will be improved to give better views of the carvings.

Kevin Sun Tak-wing, archaeology curator at the department, said most of the rock carvings - composed of geometric patterns and lines with hints of human or animal images - shared similar characteristics with the patterns seen on pottery and bronze vessels made during the Bronze Age.

'Although we cannot say for sure why the ancient people did the carvings without any information being recorded in the legends or documentaries, we believe they may be some kind of ritual for the worship of the supernatural,' he said.

'Many of these carvings were done on the steepest slopes facing the sea. They might have inscribed there to wish a safe journey to the fishing population.'

The only other place in the Pearl River Delta area where such carvings have been found is an island in Zhuhai , Mr Sun said.

'These rock carvings are important as they gave us hints of the existence of ancient inhabitants in Hong Kong and an early form of religious activities,' he said.

All eight sites have been declared monuments and put under the care of the Antiquities and Monuments Office.