Abstract: The experimental analysis of triaxial resistance to shearing and compressing on rocksshow that yleld limit and ultimate tensile strength would increase regularly along with theincrease of design confining pressure. Futhermore,in a case of same compressional force. the deeper the buried depth is for the coveriiig strata, the higher resistance to the shearing and compression strength would be for the rocks, and the less the fractures would be generated.With the combination of case studies of practical explorations, the authors setquantitative standards to estimate regional covering strata, based on the relationship of vertically hydro-geologic zoi1ing with the buried depth of a covering strata.