Interpretation　of　S-wave　data　from　Tai′anXinzhou　DSS　profile　and　its　relationship　with　Xingtai　earthquakes

作     者：宋松岩 周雪松 王椿镛 张先康 宋建立 龚怡 

作者机构：1. Research Center of Exploration Geophysics State Seismological Bureau 450003 Zhengzhou China2. Institute of Geophysics State Seismological Bureau 100081 Beijing China 

出 版 物：《Acta Seismologica Sinica(English Edition)》 (地震学报)

年 卷 期：1997年第10卷第1期

页      面：16-26页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

主　　题：S wave velocity wave velocity ratio upwarping and sloping mantle districts crust mantle transitional zone ultra crustal fault zone 

摘      要：On the basis of S wave information from Tai′an Xinzhou DSS profile and with reference to the results from P wave interpretation, the 2 D structures , including S wave velocity V s, ratio γ between V p and V s; and Poisson′s ratio σ , are calculated; the structural configuration of the profile is presented and the relevant inferences are drawn from the above results. Upwarping mantle districts (V s≈4.30 km/s)and sloping mantle districts (V s≈4.50 km/s) of the profile with velocity difference about 4% at the top of upper mantle are divided according to the differences of V s , γ and σ in different media and structures, also with reference to the information of their neighbouring regions; the existence of Niujiaqiao Dongwang high angle ultra crustal fault zone is reaffirmed; the properties of low and high velocity blocks(zones) including the crust mantle transitionalzone and the boudary indicators of North China rift valley are discussed. A comprehensive study is conducted on the relation of the interpretation results with earthquakes. It is concluded that the mantle upwarps, thermal material upwells through the high angle fault, the primary hypocenter was located at the crust mantle juncture 30.0～33.0 km deep, and additional stress excited the M S=6.8 and M S=7.2 earthquakes at specific locations around 9.0 km below Niujiaqiao Dongwang, the earthquakes took place around the high angle ultra crustal fault and centered in the brittle media and rock strata with low γ and low σ values.