图9  西海固地区平均虚波速度K₀，纵波速度ν_po及波速比γ₀变化曲线^[5]

Fig．9  Variation curves for mean velocity of imaginary wave(K₀),

        velocity of longitudinal wave (ν_po) and the velocity ratio (γ₀)

        in Xihaigu region

        异常区范围：北纬35°50′―6°15′，东经105°00′―106°20′