Pat McDonnell Twair reports from California on how American oil money could help preserve an important part of the Middle East's cultural heritage.

Since it opened to the public in December 1997, the billion dollar Getty Centre has become the architectural wonder or blunder of southern California. While some critics marvel at its stark design, others call the complex of white stone and glass structures designed by New York architect Richard Mejer an eyesore. Perched atop the Santa Monica Mountains with a panoramic view of the Pacific, the Getty's museums and restaurants have drawn more than two million visitors during its first year of operations.

One building, however, is off limits to tourists. It houses the Getty Conservation Institute (GCI), which is sponsoring research and projects to protect man's cultural heritage. It is an ambitious mission that has sent experts to Tanzania to preserve hominid footprints and to Israel to conserve a 19th century Canaanite arch.

In March 1997, the GCI joined forces with Tunisia's National Institute for the Protection of Cultural Heritage to preserve its Roman mosaics, which most art historians agree rank among the finest produced in antiquity. GCI's Dr. Gaetano Palumbo discussed the three-year project with The Middle East.

Contrary to traditional conservation procedures in which Roman and Byzantine mosaics were removed and stored or exhibited in museums, Dr Palumbo said the GCI has introduced the practice of conservation in situ. "We are convinced," he explained, "that it is preferable to leave the mosaic on the site so as to maintain its cultural context as well as to avoid traumatic interventions [during its removal]."

In Tunisia, the GCI is concentrating on Utica, a site that contains the remains of several Roman villas with largely intact mosaic floors.

"Our work is twofold," Dr Palumbo stressed. "First, we are training Tunisian specialists so they will be able to diagnose damage occurring to mosaics and perform routine maintenance. Secondly, we are trying to analyse the process of deterioration in order to arrive at the best means of preserving the mosaics."

The Tunisians agree with GCI experts that the mosaics should not be detached from their original placement. The problem is deciding the number of people who should be allowed to view the mosaics before damage may occur. The mosaics at the Utica villas have been exposed to the elements for the past three decades and the GCI team is researching the degree of deterioration of stone and glass according to exposure to the sun, rainfall and other climatic conditions.

"When we are trying to conserve mudbrick architecture, it sometimes is necessary to construct shelters and roofs over the exposed clay structures to prevent further deterioration," Dr Palumbo explained. "This is not necessarily true for mosaics. Our job is to determine the best means of preserving them - whether it means coating their surface with chemicals or daily maintenance."

Dr Palumbo is no newcomer to the Middle East. He studied under Dr Paolo Matthiae, the excavator of the 3rd millennium BC site of Ebla at Tell Mardikh, Syria, and with Dr William Dever of the University of Arizona at Tucson. He excavated at Tell Hayat in the Jordan Valley and worked from 1987 to 1992 on a joint University of Arizona-Rome University project at Wadi Al-Yabis in northern Jordan. In addition, he directed the archaeological survey at Wadi Al-Zarqa, an area 30 kilometres northeast of Amman which was threatened by urban expansion. But the project that has endeared Dr Palumbo to his Jordanian colleagues is the computerised database of 10,000 archaeological sites in Jordan which he developed in 1989.