本文首先从室内岩石力学实验数据出发，利用Biot-Gassmann方程和Pride模型建立的岩石骨架与岩石基质体积模量函数关系式求出珊溪水库区岩石基质模量和固结系数，然后分别利用联合地震波走时方程组和多台和达曲线求得P波速度和波速比，最后以流纹斑岩为例，计算了岩石饱和度、孔隙度，并分析了地震中造成的饱和度和孔隙度的变化。结果表明：①地震过程中岩石饱和度均大于99%，且大多为100%，即地震中岩石处于水饱和或接近水饱和状态，波速和波速比的变化主要由岩石孔隙度的变化引起。②珊溪水库震中区流纹斑岩孔隙度的上限值为6.6%~15.5%，下限值为3.6%~4.2%。下限值与地震前由实验室测得的孔隙度相近。如果实验室测得的流纹斑岩孔隙度是其初始值，则地震中岩石孔隙度增大了3.2%~12.09%。③2008年1月地震以后震中区岩石孔隙度逐渐闭合，直到2014年8月孔隙度开始迅速增大，9月15日起原震区再次发生一组新的地震活动，震群活动前岩石出现了扩容现象。

In this paper,based on the experimental data of rock mechanics,the matrix modulus and consolidation coefficient of rock in the Shanxi reservoir area were obtained by the method of combined Biot-Gassmann equation and Pride model. Then the P wave velocity and the wave velocity ratio were obtained by solving the combined seismic wave travel time equation group method and the multi station method. Finally,we calculated the rhyolite porphyry saturation and porosity,and analyzed the changes of rock saturation and porosity. The results are as follows:(1)The rock saturation were greater than 99%,and the greatest was 100%,that is to say,the earthquake rocks are always in water saturation or near saturation. Wave velocity and wave speed ratio change is mainly caused by the change of porosity.(2)The rhyolite porphyry porosity of the upper limit is 6.6%~15.5%,and the lower limit value of 3.6%~4.2%. The lower limit values are close to the porosity measured by the laboratory before the earthquake. If the hyolite porphyry porosity laboratory measurement is the initial value,rock porosity during the earthquake increases by 3.2%~12.09%.(3)In 2008,after the earthquake epicentral area rock porosity gradually closed,until August 2014 porosity began increases rapidly. From September 15 on,a new set of seismic activities occurred again in primary seismic zone,and rock porosity showed an increase before this group of seismic activity.

P315

浙江省公益技术研究社会发展项目（2012c23035、2014C33050）资助