Artificial intelligence and digital scanning technologies are being used to preserve and restore the ancient murals of the Kizil Cave-Temple Complex in Baicheng county, Xinjiang Uygur autonomous region, according to researchers involved with the project.

The massive complex contains 349 caves, with nearly 4,000 square meters of murals. Carving began around the 3rd century, making Kizil China's earliest large-scale grotto complex.

In Cave 161, dome ceiling paintings in the main chamber have long been obscured by soot. To recover what lies beneath without risking further damage, researchers are applying terahertz time-domain spectroscopy, a noninvasive scanning technique that penetrates the soot and extracts pigment information and linear contours without touching the surface.

Zhao Li, director of Qiuci Academy's institute of digital technology and documentation information, said this marks the first application of such multimodal fusion technology — combining terahertz scanning, X-ray fluorescence, and structured-light 3D scanning — in cultural heritage conservation anywhere.