天水仙人崖石窟壁画颜料层原位-无损分析研究

壁画是我国极为重要的文化遗产类型，具有极高的历史价值、艺术价值、科学价值、文化价值和社会价值。颜料层作为壁画的核心价值所在，包含古代历史文化、宗教信仰、政治经济、科学技术等多方面的信息内涵。常规的颜料层分析方法有原位无损和微损取样两种，取样分析方法虽能满足这类珍贵、脆弱文物的研究，但获取样品数量有限且会对本体造成不可逆转的损伤。综合运用数字成像以及光谱等分析技术对天水仙人崖石窟壁画颜料层进行工艺与制作材料研究。结果显示，正射影像图能够真实记录壁画当前纹理信息，色度仪可以量化表征壁画颜料的颜色，红紫外摄影可以提取可见光下不易探查的壁画绘制线稿、修复痕迹等隐含信息，高倍数码显微镜可观察壁画表面的微观形态及破损处的层次信息，便携式X射线荧光光谱仪可检测出颜料中的元素由此判断主要显色元素，高光谱采集所得数据与标准图谱比较后能够准确判定颜料的矿物种类。因此，多种原位无损分析方法的联合运用，可以减少对文物的直接干预，亦可达到对壁画颜料层认知的目的。这些非接触式的无损检测方法，可精细化研究壁画颜料层的色彩、物理、化学属性等内容，是壁画现场分析的重要手段，可在石窟寺、寺观殿堂、墓葬壁画的研究上进行推广，发挥其应有之用。

The Application of Nondestructive In-Situ Analysis on the Murals of the Xianrenya Grottoes in Tianshui

The mural is an extremely important type of cultural heritage in China, with historical, artistic, scientific, cultural,and social value. The paint layer is the core value of the mural cultural relic, which contains important information and connotation of the ancient history and culture, religious belief, political economy, science and technology. The conventional and research methods are divided into nondestructive in-situ analysis and micro damage sampling. Although the sampling analysis method can satisfy the research of this precious and fragile cultural relics, the number of samples obtained is limited, and it causes irreversible damage to the noumenon. This paper uses digital imaging and spectral analysis to analyze the material and technology of the paint layers of Xianrenya grottoes in Tianshui. The results show that orthographic image can record the texture morphology information of the murals. Colorimeter can quantify the color of the pigments. Infrared-ultraviolet photography can extract hidden information such as drawing lines and repairing traces of murals wich are not easy to detect under visible light.High-power digital microscope can observe the micro morphology of the mural surface and the hierarchical information of damaged parts. Portable X-ray fluorescence spectrum can detect the color elements in the murals. After comparing the data collected by Hyperspectral with the standard spectrum, the mineral types of the pigment can be accurately determined. Therefore, using various kinds of nondestructive in-situ analysis can reduce the direct intervention on cultural relics and achieve the purpose of understanding the material and technology of the paint layers of murals. These non-contact and non-destructive testing methods can study the color, physical and chemical properties of the paint layer of murals systematically. They are all important and rapid means of nondestructive and in-situ analysis murals. They can be widely used in the study of grottoes, temples and tombs.