Abstract: In this paper, the geological and development characteristics in the FQ oilfield in the Tarim basin were analyzed, and then the productivity test method, choke flow method and reservoir numerical simulation method were developed to optimize the reasonable productivity in ultra-deep fault-controlled fractured-vuggy reservoirs. The results show that the primary oil recovery of ultra-deep fault-controlled fractured-vuggy reservoirs can be divided into early stage, middle stage and late stage, which differ greatly in development characteristics. The ultra-deep fault-controlled fractured-vuggy reservoirs in the FQ oilfield exhibit four types of productivity test curves: convex, linear, upturned and stepped. For wells showing the convex curves, the productivity at the inflection of the curves is the reasonable productivity. For wells showing the linear and upturned curves, the maximum test productivity is the reasonable productivity, but the choke testing productivity needs to be continuously expanded until the inflection of the curves appears. For wells following the stepped curves, the maximum test productivity after reaching the step will be the reasonable productivity. When the well productivity is optimized by the choke flow method, the productivity at the inflection of the choke flow curves is the reasonable productivity. The reservoir numerical simulation method is applicable in optimizing the well productivity in the middle and late stages of primary oil recovery, that is, the reasonable productivity is determined by optimizing the key indicators such as water breakthrough time, cumulative oil production, and recovery rate.

Key words: Tarim basin, fractured-vuggy reservoir, ultra-deep layer, fault-controlled, reasonable productivity, productivity test, choke flow method, reservoir numerical simulation