CALCULATING MODEL OF EQUIVALENT ROCK MECHANICAL PARAMETERS OF SAND-MUD INTERBED AND ITS APPLICATION

On the basis of the deformation analysis of rocks and on the sense of energy, the general calculating formula of the equivalent rock mechanical parameters is deducted using strain energy theory and energy conservation law, and the logging data calculating model is established. The equivalent rock mechanical parameters of Bashijiqike Formation, the subject reservoir in Kela-A gas field, Kuqa depression, are calculated by the model, and the numerical simulation of stress field and reservoir fractures is carried out on the basis of the calculating result. The simulation demonstrates that reservoir fractures mainly develop on high spot of anticlines and monoclinal structure. This is generally consistent to the current developing practice, and thus the rationality of the model is proved. At last, the advantages and using conditions of the logging data calculating model of equivalent rock mechanical parameters are discussed. It is pointed that the equivalent rock mechanical parameters are suitable for regional and horizontal prediction of stress field and reservoir fractures, not for partial or vertical prediction of distribution regularity of reservoir fractures.