为保证试井解释出充足而准确的油藏信息，需要足够长时间的测试数据。针对海上低渗透气藏压力恢复试井测试时间长、成本高的问题，通过推导反卷积试井模型，用Matlab编制反卷积算法，提出基于反卷积处理的压力恢复试井分析操作步骤，实现了用短期压力恢复数据和生产数据反演气藏压力响应历史的过程，大幅度节省了时间并降低了成本。通过数值试井算例验证了此方法的正确性。研究表明，对于渗透率为1×10-3 μm2地层，水力裂缝半长为120 m无限导流裂缝的压裂气井，需要关井测试22 h才可以探测到地层径向流，若使用反卷积压力恢复试井分析，仅需要1 h的压力恢复数据即可合理计算压裂施工参数。最后，东海低渗气田1口压裂井的现场应用证明了该方法的可行性。
Current well test analysis techniques are mainly based on the analysis of individual flow periods, usually the longest build-up period in the test. They provide limited reservoir information and sometimes an incorrect diagnosis of the reservoir model. In this paper, a deconvolution-based pressure buildup analysis method evolved with our deconvolution algorithms is proposed to solve the costy test issue of offshore low-permeability gas reservoirs. The proposed method utilizes short-term pressure buildup and long-term flowrate history to recover the true reservoir pressure response. The workflow for the proposed method is provided, and a synthetic case is used to verify the correctness of the method. It is shown that for fractured gas wells with 1md permeability formation, 120m fracture half-length and infinite conductivity, it takes 22 hours of buildup testing to detect the formation radial flow regime, while using the proposed method, it only takes 1 hour to finish the fracturing parameters calculation as long as production history before the test is available, which greatly saves time and cost. A field case in China East Sea is further presented to prove the feasibility of the proposed method.
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