Abstract: A mathematical model of unsteady percolation for well with finite conductivity vertical fractures considering thresbhold pressure gradient is developed. Its typical productivity performance curves are drawn and analyzed. The analysis shows that the longer the producing time, the greater the thresbhold pressure gradient is, and the faster the production decline is. The fractural conductivity and skin effect have a great effect on the initial productivity of fractured well. The greater the fractural conductivity, the higher the output of fractured well is, but the lower the extent of the incremental production is; the more obvious the skin fect, the lower the output of fractured well. These are of significance for in-depth understanding of the producing performance of well with finite conductivity vertical fractures in low permeability reservoir.

Key words: vertical fracture, productivity, thresbold pressure gradient, pressure, conductivity