Supplement to SPE 22681, interpretation of responses of commingled systems with mixed inner and outer boundary conditions using derivatives Academic Article uri icon


  • This supplement documents information that should amplify remarks made in the text of this paper. Appendix A presents additional computations that discuss bounds for the average pressure of the most-depleted layer, and derivative responses when both layers are bounded. In appendix B we examine the effect of layer skin factors on buildup responses for two-layer systems. These results extend our observations derived from the responses shown in Figs. 1 and 5. Appendix C examines three-layer systems and extends conclusions noted for two-layer systems. Here, we discuss all four issues examined for two-layer systems: effect of layer depletion during the test, backflow, bounds for average pressures in the layers and the effect of producing time. It also presents a discussion of the influence of a low-permeability layer on the well response. We show that the layers with a larger flow capacity dominate the pressure response curve. Appendix D briefly addresses the stimulation of individual layers. In Appendix E, an example application demonstrating the analytical procedure to evaluate pressure buildup measurements after a layer has depleted during a test is discussed. Appendix F documents formulate needed to compute pressure distributions by the probe-radius concept.

author list (cited authors)

  • Gao, C., Jones, J. R., Raghavan, R., & Lee, W. J.

complete list of authors

  • Gao, C||Jones, JR||Raghavan, R||Lee, WJ

publication date

  • December 1994