纵横波速度是各种岩石物理性质与地震勘探的桥梁,通过纵横波速度研究可以对储层岩性、物性和流体进行有效识别。然而在实际研究中往往缺乏横波资料,这就需要对横波速度进行估算。目前碎屑岩地区横波速度预测研究已经很成熟,而碳酸盐岩储层由于复杂的岩性和孔隙结构,严重影响横波速度预测精度,造成横波预测研究发展缓慢。Xu-Payne模型通过考虑不同孔隙类型(粒间孔、孔洞及裂缝)对弹性波速度的影响,理论上能够有效预测碳酸盐岩储层的横波速度。阐述了基于Xu-Payne模型的横波速度预测方法,分析了碳酸盐岩不同孔隙形状(包括洞穴、粒间孔、裂缝)对速度的影响,对其在碳酸盐岩地层中的适用性予以解释。最后利用不同模型对碳酸盐岩实际资料进行了横波速度预测,通过比较,Xu-Payne模型法预测结果精度比Xu-white模型高2.9%,同实测横波速度吻合更好。 P-wave velocity is a bridge between the physical properties of various rocks and seismic exploration. Through the study of P- and S-wave velocity, the lithology, physical property and fluid of reservoirs can be effectively identified. However, the shear wave data are often lacking in practical research, which needs to estimate the shear wave velocity. At present, the research on the prediction of S-wave velocity in clastic rocks is very mature. However, due to the complex lithology and pore structure, carbonate reservoirs seriously affect the accuracy of S-wave velocity prediction, resulting in the slow development of S-wave prediction. The Xu-Payne model theoretically can effectively predict the shear wave velocity of carbonate reservoirs by considering the influence of different pore types (intergranular pores, pores and fractures) on the elastic wave velocity. The shear wave velocity prediction method based on the Xu-Payne model is described. The influence of different pore shapes (including caves, intergranular pores and fractures) on the velocity of carbonate rocks is analyzed and its applicability in carbonate strata is given Explanation. Finally, different models are used to predict the actual shear-wave velocity of carbonate rocks. By comparison, Xu-Payne model prediction accuracy is 2.9% higher than that of Xu-white model, which is in good agreement with the measured shear wave velocity.