Analytical Investigation Of Conservation Status And Manufacturing Technique On Mural Paintings In The Fengguo Temple,Yixian,Liaoning Province

Fengguo temple is located in Yixian,Jinzhou City,Liaoning Province,which is the largest single storey wooden architecture in ancient Chinese Buddhist temples.There are more than five hundred square meters murals remaining in the temple.Murals of fengguo temple have extraordinary historical,artistic and scientific value,and they became precious material information for researching political,economic and cultural development of ancient China.Nevertheless,these murals are in poor conservation condition and in need of relevant research and conservation pressingly.In this article,a comprehensive status investigation of murals of fengguo temple have been done.According to modern analytical technologies,the making materials and technology of murals have been detected.And combined with the monitoring of conservation environment of murals,we analyse the mechanism of murals' disease,which can provide basis for future restoration and preservation.According to comprehensive status investigation,there are about 67.5 square meters mural of Ming dynasty and 466.7 square meters mural of Yuan dynasty existing in Fengguo temple.And the disease of Ming dynasty is 32.4 square meters,area of disease is small,which causes little damage.The conservation situation of Ming dynasty's murals is good.And the disease of Yuan dynasty is 466.7 square meters,area of disease is big,which causes bigger damage.The conservation situation of Yuan dynasty's murals is not good.Gathering environmental data of Yixian region and monitoring of conservation environment of murals show that the climate in Yixian has influenced the conservation environment of murals a lot.According to monitoring of conservation environment of murals,we realize that temperature,illumination and humidity inside the temple have adverse influence on the conservation of murals.In this article,we have done a comprehensive and systematic analysis of lime layer,plaster layer and paint layer by scientific methods,including x-ray fluorescence(XRF),x-ray diffraction(XRD),polarized light microscopy(PLM)and micro-Raman spectroscopy.The analytical results of plaster layer shows that earthen layer is composed of quartz,plagioclase,illite,calcite and little amphibole.In addition,analytical results indicate that the major component of lime layer are kaolin and calcite.Lastly,results of paint layer show that all the pigments used in murals are inorganic mineral pigments apart from the blue pigment including Cinnabar,red lead,red iron oxide,atacamite,carbon black and so on.According to cross-section analysis and investigation on-site,we can draw a conclusion that the mural paintings in Fengguo Temple consist of five parts:support layer(brick wall,earthen wall and epoxy resin glass cloth),coarse plaster(1.5-2cm),fine plaster(0.5cm),grounding layer(60-200?m)and paint layer(10-200?m).What's more,we also found that most of mural paintings had been re-painted and restored.Analysis of disease mechanism shows that the main reason of detachment is thermal expansion coefficient of two materials has great difference.Flaking has a link with manufacturing process of murals and exterior reinforcement material.And disruption is chiefly caused by movement of water and salt.Through the analysis of the cause of disease,it provides a theoretical basis for conservation and repair of the murals.