苏里格气田压裂气井合理关井测压时间

为了解决压裂气井压力恢复曲线不能出现边界反映段，以及渗流不能反映地层中真实流动特征的问题，基于苏里格气田低渗透气藏压裂气井试井和实际生产资料，利用现代试井解释理论，研究了合理关井时间的界限及其计算方法。结果表明，当油井关井测压时间达到3倍地层径向流开始出现的时间后，利用此时的压力数据，解释地层参数和地层压力，其结果的误差小于5%，同时能较准确地判断边界类型。计算的理论曲线和霍纳法解释值非常接近，对于苏里格气田压裂气区而言，若预先知道某生产井地层有效渗透率值，可从理论曲线查出压力恢复试井的关井时间，否则，建议按照该井区地层有效渗透率，将不稳定试井测试时间定在以10 d以上为宜。

DETERMINATION OF REASONABLE SHUT-IN PERIOD FOR PRESSURE MEASUREMENT IN FRACTURED GAS WELLS OF SULIGE GAS FIELD

Because the pressure buildup curves of fractured gas wells cannot reflect the  boundary effect and the flow is not representative of real flow in the formation, this paper conducted a study on reasonable shut in time and its calculation method based on well test and production data from gas wells in low permeability reservoirs of Sulige gas field. It can be seen from the results, when the shut in time triples the time for radial flow to begin, the interpretation errors of formation parameters and pressure are less than 5%, the boundary types can be accurately identified, and the calculated theoretical curves match Horner type curves very well. For fractured regions in Sulige gas field, the shut in time can be determined from the theoretical curves if the formation effective permeability is known; otherwise, shut in time longer than 10 days is recommended providing that the effective permeability is about 0.8×10-3μm2.