遥感-岩石力学(II)——断层双剪粘滑的热红外辐射规律及其构造地震前兆意义

以构造地震孕震机制之二即断层粘滑发震为模拟对象,利用双轴加载实验系统和红外热像仪,对4类断层组合条件下双剪粘滑过程中的红外辐射温度场的时空演变特征进行了模拟实验研究.研究表明断层表面温度场的时空演变不仅与应力水平有关,还与组成摩擦面的两侧岩性及其粗糙度有关.具体表现在(1) 应力集中和摩擦作用强的区域,其红外辐射较强;而应力松弛和摩擦作用弱的区域其红外辐射较弱.(2) 当两断层岩性及摩擦面条件对称时,红外热像呈双蝶翼形;当摩擦面粗糙,红外热像呈非对称、非均衡时空演变特征,如串珠状、针状、倒针状、条带状、单蝶翼形或其依次变化.卫星热红外遥感与差分干涉雷达(D-INSAR)技术相结合,并以活动断层预滑及其后续粘滑为监测重点,可望成为构造地震遥感监测和地震短临时-空-强预报的新途径.

REMOTE SENSING-ROCK MECHANICS(II)--LAWS OF THERMAL INFRARED RADIATION FROM VISCOSITY-SLIDING OF BI-SHEARED FAULTS AND ITS MEANINGS FOR TECTONIC EARTHQUAKE OMENS

The viscosity-sliding of bi-sheared faults is the second mechanism of tectonic earthquake. By using of biaxial loading system and thermal infrared (TIR) imaging system,the TIR radiation features of four kinds of composed faults were experimentally studied in the process of bi-sheared viscosity-sliding. It is revealed that the time-space evolution of rock surfaces TIR radiation temperature field is not only related to stress,but also to the conditions of friction surface as well as the rock properties of its both sides. The TIR radiation is stronger in the location of stress concentration and strong friction than that in the location of stress relaxation and weak friction. In condition of symmetrical rock properties and friction surface of both faults,the TIR image is double butterfly-wings shaped. In condition of rough friction surface,the time-space evaluation of TIR image is un-symmetrical and un-balanced e. g. beads-shaped,needle-shaped,suspended needle-shaped,strip-shaped,single butterfly-wings shaped or shape changed in sequence. If satellite TIR remote sensing is combined with differential INSAR technology,and the pre-sliding action and its subsequent sliding actions of active faults are taken as the monitoring focuses,it would be a prospecting new technology for the remote sensing monitoring and the short-term-time-location-magnitude forecasting for tectonic earthquake.