The experimental studies on influence of periodic layered media to P-wave velocity
Wei Jian-xin1,2,3, Di Bang-rang1,2,3
1. State Key Lab of Petroleum Resource and Prospecting, China University of Petroleum, Beijing City, 102249, china;
2. CNPC Key Lab of Geophysics, China University of Petroleum, Beijing City, 102249, china;
3. Faculty of Resource and Information, China University of Petroleum, Beijing City, 102249, China
Abstract：Periodic layered medium model is alternatively composed of two materials of different acoustic impedance and its velocity is not only controlled by the lithology of each layer,but also related to the thickness of the medium and the detection frequency. In order to better understand the influence of the factors,a periodic layered medium model with different thickness for each layer was constructed by infusing one material into another and then transmission observation to the model was conducted by using sources with 1,0.6,0.2 MHz as dominant frequencies respectively; through recording the waveform variation during the propagation in the vertical layered media,the influence of different periodic layer thickness d to wavelength λ and velocity V,and the relationship between V and λ/d was analyzed.The research results showed that when the volume of each material is close to each other,V and λ/d are related in vertical direction,that is,λ/d is less than 1,V is consistent with average velocity; when λ/d is between 8 to 11,V drops rapidly,the minimum of V is close to the effective medium estimated velocity in the periodic layered medium. When λ/d is close to 1 or 8,it is turning point for velocity variation,at the same time the energy of the transmitted wave severely attenuated.
魏建新, 狄帮让. 周期层状介质对纵波速度影响的实验研究[J]. 石油地球物理勘探, 2010, 45(5): 661-666.
Wei Jian-xin, Di Bang-rang. The experimental studies on influence of periodic layered media to P-wave velocity. OGP, 2010, 45(5): 661-666.
