Gansu takes measures to help Millennium North Cave Temple fight "Aging"
Xinhua News Agency, Lanzhou, 15 Nov (Reporter Liang Jun) in front of a stone statue covered with moss, staff of the Cultural relics Protection Research Institute of the North Cave Temple of the Dunhuang Academy regularly monitor the water content, weathering degree, and groundwater level on the surface of the rock mass. The purpose of this paper is to provide basic data for delaying the "aging" of cultural relics in North Cave Temple.
"the North Cave Temple is 1510 years old and is in the stage of accelerated weathering. When it is serious, it will drop 1.5 kilograms of sand per square meter per year, and 107 kilograms of sand will fall at the top of Cave 32 in 2016." Wu Zhengke, director of the Institute of Cultural relics Protection of the North Cave Temple at the Dunhuang Academy, said that due to the exposure of many cave niches and the abundance of groundwater in the region, the annual rainfall is relatively heavy, and the grotto statues are aging in the wind and rain.
North Cave Temple is located in Qingyang City, Gansu Province, 25 kilometers away from the loess slope. According to historical records, the North Cave Temple was built in the second year of Northern Wei Yongping, that is, AD 509. After successive dynasties, it has been continuously expanded to form a grotto group with dense niches. At present, there are 308 large and small cave niches and more than 2000 grotto statues, which are distributed on the yellow sandstone cliff face on both sides of the Puhe River and play an important role in the art of Buddhist grottoes in China.
Wu Zhengke said: after the Qin and Han dynasties, the North Grottoes area developed into an important node of the Silk Road in Longdong, Gansu Province. There are five ancient roads interlaced here, and there are ruts formed by long-term rolling on the ancient roads. Witnessed the prosperity of the Silk Road cultural and trade exchanges.
"but after the wind, the sun and the rain, some of the stone statues lost their old face and became blurred." Wu Zhengke said that the water absorption of yellow sandstone is strong, and the water volatilizes soluble substances in the process of evaporation, resulting in loosening, weathering and shedding of the rock mass.
Delaying the "aging" of sandstone grottoes is a worldwide problem. In 2017, in order to strengthen protection, Gansu Province put the entire system of the North Cave Temple under the management of the Dunhuang Research Institute. In 2018, the "Research on key Technologies of weathering Protection of Sandstone Grottoes" carried out by Dunhuang Research Institute was listed as a major special project in Gansu Province. The project, together with experts from Dunhuang Research Institute, Lanzhou University and Northwestern University, plans to make breakthroughs in the study of disease mechanism and weathering and shedding protection of sandstone relics in North Cave Temple for at least five years. Relevant experts believe that this will not only promote the protection of cultural relics in the North Cave Temple, but also conducive to the protection of sandstone grottoes and cultural relics in Longdong and even Northwest China.
In 1988, the North Cave Temple was announced by the State Council as the third batch of national key cultural relics protection units. In recent years, in order to slow down the development of various diseases, the cultural relics protection staff of the North Cave Temple have monitored the occurrence environment of cultural relics and the changes in the cave areas, and provided the monitoring data to the Dunhuang Academy in order to formulate a protection plan suitable for the North Cave Temple. Extend the "life" of cultural relics.