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已发表的实验室研究论文提出,地震压缩波(纵波)与切变波(横波)速度比(V_p/V_s)和沉积岩岩性之间有一种联系。把某些理论模型与这些实验室研究结果做比较认为,裂隙或孔隙几何形状对观测到的V_p/V_s值的影响要比它对组成基质矿物的弹性常数的影响大些。而且可以推断出,在岩性与V_p/V_s之间所观测到的密切联系就是岩性与孔隙和裂隙几何形状分布之间联系的结果。其次是对各种岩性的裂隙形状做直接观测,以加强这些推断。本研究论文评论了V_p/V_s与岩性之间的实验关系,并且研究了两个已发表的裂隙弹性介质理论模型。这两个模型都揭示了砂岩的地震速度10~(-1)到1范围以内的裂隙及孔隙的纵横比控制,其中白云岩纵横比在10~(-2)到10~(-1)范围以内,而致密灰岩孔隙度一般较低,其纵横比在10~(-3)到10~(-2)范围以内。对沉积岩裂隙与孔隙的纵横比做直接观测,可以验证上述这些推断,以及为物理和地质上了解V_p/V_s比的岩性解释提供了依据。
Published laboratory research papers suggest that there is a relationship between the seismic compression wave (P-wave) and shear wave (shear wave) velocity ratio (V_p / V_s) and sedimentary rock lithology. Comparing some theoretical models with these laboratory studies suggests that the effect of fracture or pore geometry on observed Vp / Vs values is greater than its effect on the elastic constants of the matrix minerals. And it can be deduced that the close relationship observed between lithology and Vp / Vs is the result of the connection between lithology and the distribution of pore and fracture geometries. The second is direct observation of various lithology fracture shapes to reinforce these inferences. The present paper reviews the experimental relationship between V_p / V_s and lithology and studies two published theoretical models of elastic media for fractures. Both of these models reveal the aspect ratio control of fractures and pores within the seismic velocity range of 10-1 (-1) to 1, in which the dolomite aspect ratio is in the range of 10 -2 to 10 -1 , While the density of tight limestone is generally low, with aspect ratios ranging from 10 -3 to 10 -2. The direct observation of the aspect ratio of sedimentary rock fissures and pores verifies these inferences and provides a basis for understanding the lithology of the V_p / V_s ratio physically and geologically.