| Popis: |
"Stress shadowing", where the creation of hydraulic fractures affect the stresses in certain parts of the reservoir, has the dual effect of assisting and hampering the generation of hydraulic fracture stimulation in horizontal wells. In this paper, the stress contrast and pressure profiles around the near wellbore regions of a horizontal wellbore with the presence of packers and hydraulic fractures are investigated. This was accomplished by using a finite element software package where the numerical results of the behavior of the stress envelopes and stress shadowing phenomena could be evaluated and different sensitivities analyzed. From the results obtained, it is concluded that packers with higher pressure generation allow for easier fracture initiation as compared to packers with lower pressure generation. Additionally, modeling indicates that the weakest point for fracture initiation in a wellbore with a packer is at the ends of the packer. When two packers, with differing pressure generations, are placed in the wellbore, fracture initiation will occur near the packer with the higher pressure generation. Finally, it can be concluded that in areas of high stress concentration, the ability to generate hydraulic fractures is reduced as compared to areas of low stress concentrations. |
