Stress–strain analysis in productive gas/oil reservoirs

摘要: A numerical study of the stress–strain distribution in a thin disc-shaped reservoir embedded poro-elastic half-space and subject to unit pore pressure decline is presented. The results are then compared with those geometrically equivalent porous cylindrical body which either free or prevented from expanding laterally (oedometric analogy). analysis based on linear theory poro-elasticity solved aid finite element method. strength source provided by gradient generated small region surrounding gas/oil field where dissipates. influence burial depth c also investigated. show that rock undergoes vertical compaction δ independent very close confined cylinder. confinement factor similar. horizontal displacement is, however, much larger. Its maximum value occurs at boundary same order magnitude as δ. In addition, outer margin shear stresses develop totally missing both constrained cylinders. It shown displacements top bottom, well radial ones, sensitive c, especially shallow formations. Finally, largest stress found be related gradient, i.e. size neighbouring volume vanishes. Copyright © 1999 John Wiley & Sons, Ltd.