顺9井区志留系柯坪塔格组下段低孔、特低渗储层岩石物理研究

Petrophysical Research of Low-porosity and Ultra-low-permeability Reservoirs in the Lower Member of Silurian Kepingtage Formation in Wellblock Shun 9

顺9井区志留系柯坪塔格组下段埋深大,为低孔、特低渗储层.由于测井曲线受井眼影响大,波阻抗对储层和流体不敏感,为此通过岩石物理试验来研究志留系的储层岩石物理特征和储层、流体的敏感参数.压力对砂岩纵、横波速度的影响比泥岩大,砂岩和泥岩的纵、横波速度均随着温度的变大而减小;纵、横波速度与波阻抗结合能够较好地区分砂、泥岩;当入射角较大时,利用弹性阻抗可以比较好地区分砂、泥岩;纵横波速度比对储层的识别效果较好.通过对试验参数和定义的参数排序,指出了研究区最佳的流体敏感参数.

The reservoir of lower member of Silurian Kepingtage Formation in Wellblock Shun 9 was deeply buried and it was a low-porosity and low-permeability reservoir. Wave impedance was insensitive to the reservoir and fluid because the well logging curve was seriously affected by borehole. Therefore, the petrophysical characteristics of Silurian reservoir and the sensitive parameters of reservoir and fluid are studied by rock physics test. The influence of pressure on the longitudinal and shear wave velocities of sandstone was greater than that of mudstone. The longitudinal and shear wave velocities of sandstone and mudstone decreased with the increase of temperature. The combination of longitudinal, shear wave velocity with wave impedance could distinguish sand and mudstone well. When the incident angle was large, the sand and mudstone could be separated better by using elastic impedance, and the velocity ratio of P-S wave was better for reservoir identification. By sorting the tested and defined parameters, the optimal fluid sensitive parameters in the study area are pointed out.