THE CHARACTERISTICS OF SHEAR-WAVE SPLITTING PARAMETERS IN THE PRESENCES OF TWO WEAK AZIMUTH ANISOTROPIC LAYERS
LIU XI-QIANG; ZHOU HUI-LAN; ZHENG ZHI-ZHEN; GAO-YUANLI-HONG; MA YAN-LU; LIANG KAI-LI(Graduate School, University of Science and Technology of China, Beijing 100039, China)(Center for Earthquake Data and Information, SSB Beijing 100045, China)(Seismologic
Based on the balance equation and stress-strain relationship, this paper sets up the propagation equations of body waves in amsotropic mediuxn, and gets the exact solusions of the velocities of the three body waves varying with the medium's elastic parmeters and direction of wave propagation. Based on this, Studies the chameteristics of shear wave splitting parameters in the presences of one and two weak azimuth anisotropic layers, and gets the analytical solutions of synthetic splitting parameters varying the individual splitting parameters of the two layers and the incident azimuth angles. Assumed splitting paraxneters of each single layef, getS thesynthehc diagrarns. StUdied resultS reveals four individua waves split in the case of two weak azimuth anisotropic mediums can be described by a splitting operator. The synthetic splitting parameters exhibt systematic variations as a function of incoming polarizahon with π/ 2 periodicity, as differs from single anisotropic medium. The derived expressions can be used to invert for the individual properties of the two layers in many circurnstances and explain plate movement mantle convection scale, deep earthquake cause, shallow earthquake tectonics and deep foree source.