地震断层摩擦滑动过程中的物理-化学行为是认识地震破裂机制和孕震环境的重要内容。假玄武玻璃作为地震化石记录了深部地震断层破裂的相关信息，是认识地震断层力学性质和地震孕育环境的重要物质组成。本申请选择青藏高原东缘龙门山断裂带地表露头和汶川科钻岩心中不同深度发育的多期次假玄武玻璃及其围岩（碎裂岩）为研究对象，通过对多期假玄武玻璃进行物理-化学性质测试和显微-超微构造学研究，以及对其围岩碎裂岩开展不同条件下的高速摩擦实验和高温熔融实验，识别假玄武玻璃形成时和后期改变的物理-化学性质与结构特征；结合同位素年代学研究，建立假玄武玻璃形成后物理-化学性质与结构变化的演变过程。在此基础上，综合分析龙门山震源/近震源区强震孕震环境和断层破裂机制，不仅有助于完善地震断裂理论、深化地震机理的认识，而且为地震灾害的预报预警提供科学理论依据。

The physical-chemical behavior of the seismic faults during their frictional slip is of great importance in understanding the seismic rupture mechanisms and their seismogenic environment. Known as earthquake fossil, pseudotachylyte preserved the information on deep seismic fault rupture, is a vital material for learning the mechanical properties of seismic fault and the earthquake nucleation environment. Here in this application, we focus on the multiple-generations of pseudotachylytes and their surrounding rocks (cataclasites), which exposed at the Bajiaomiao outcrop and developed at different depths in the Wenchuan earthquake Fault Scientific Drilling (WFSD) cores along the Longmen Shan fault belt, at the eastern margin of the Tibetan Plateau. Based on multidisciplinary approach, which includes field and laboratory study of the natural pseudotachylytes intergrated with theoretical and rock frictional experiments and high-temperature heating experiments, the pristine and altered features of pseudotachylyte will be indentified via physical-chemical and microstructural analyses, and comparation studies with the experimental products. Together with the isotopic chronology study, the alteration processes of physical-chemical properties and structural changes in pseudotachylytes is expected to be established. A comprehensive discussion of seismogenic environment and fault rupture mechanisms of large earthquakes in the Longmen Shan area at/near seismogenic depth will be addressed. The research results will not only help to improve the theory of seismic rupture and increase our understanding of seismic mechanism, but also yield a theoretical basis for predicting and early warning of earthquake disasters.