Paleocaves in carbonate reservoirs are the excellent oil and gas storage spaces in the field of petroleum exploration. Predicting the collapse depth of paleocaves in carbonate reservoirs has essential theoretical significance and applicable value for classifying of reservoir quality and delimiting lower depth of oil and gas exploration. Paleocaves in carbonate reservoirs are acted by overburden pressure, tectonic lateral compression, and fluid pressure in caves. In this study, paleocaves with irregular boundary shapes were abstracted as spheres with different diameters. Mechanical model of surrounding rocks of paleocaves was established to compute the stress states in 3–5 times diameter of caves. Through analyzing stress states in surrounding rocks, the destruction and collapse of caves was investigated. The diameters of caves in these models range from 0.01 mm to 10 m. Relationship between diameter of cave and collapse depth was obtained by fitting collapse depth of caves with different diameters. Above the collapse depth of caves with diameter 5 m is good reservoir zone. Between the collapse depth of caves with diameter 5 m and 2 m is effective reservoir zone. The interval of collapse depth of caves with diameter 2 m and 0.5 m is general reservoir zone. Below 11000 m, karst caves in carbonate reservoir nearly disappear. Numerical model of real paleocaves was established to simulate the deformation of single paleocave and paleocave group. The relationship between displacement of paleocave wall and depth of paleocave obeyed power law. The contiguous destruction and collapse occurred first between the paleocaves with small distance. The relationship can be used to classify the quality of carbonate reservoir and predict the lower depth of petroleum exploration.

碳酸盐岩储层中的古猿是石油勘探领域中极好的油气储藏空间。预测碳酸盐岩储层古孔隙塌陷深度具有重要的理论意义和应用价值，对储层质量进行分类，界定油气勘探的下限。碳酸盐岩储层中的古白垩纪受到上覆压力，构造横向压缩和溶洞中的流体压力的作用。在这项研究中，具有不规则边界形状的古树被抽象为具有不同直径的球体。建立了古洞穴围岩力学模型，以计算洞直径3-5倍的应力状态。通过分析围岩的应力状态，研究了洞穴的破坏和坍塌。这些模型中的洞穴直径范围为0.01 mm至10 m。通过拟合不同直径的溶洞的塌陷深度，得到溶洞直径与塌陷深度之间的关系。大于5 m的洞穴塌陷深度以上是良好的储层带。在直径为5 m和2 m的洞穴塌陷深度之间是有效的储层带。直径2m和0.5m的洞穴塌陷深度的间隔为一般储层带。11000m以下，碳酸盐岩储集层岩溶洞穴几乎消失。建立了真实的古腔数值模型，模拟了单个古腔和古腔群的变形。古洞壁位移与古洞深度的关系服从幂律。连续破坏和塌陷首先发生在距离较近的古草之间。