Because P and S waves travel at different but fairly constant speeds, the interval between their arrivals increases in proportion to the distance from the earthquake focus, or initial rupture point.

由于 P 波和 S 波以不同但相当恒定的速度传播，它们到达的间隔与到震源或初始破裂点的距离成比例地增加。

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With the measured P and S wave velocities and log-derived densities of the same interval, rock mechanical parameters of this pre-borehole are roughly calculated.

提取出其中的纵波、横波速度信息，并与实验室岩心声波测量结果和测井结果进行了对比。

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