数值试井方法在致密油水平井压力评价中的应用

Application of Numerical Well Test Method in Pressure Evaluation of Tight Oil Horizontal Wells

大庆油田致密油水平井普遍采用体积压裂法投产,压力双对数曲线会表现复杂边界、物性变化或邻井干扰等变化,常规试井方法无法得到满意的拟合结果,在评价致密油水平井地层压力误差较大。针对上述问题,采用数值试井方法解释了大庆油田致密油3口水平井。从3口井的压力拟合曲线特征出发,对比不同地层条件下,曲线特征的差异,间接反映了数值试井方法的准确性,同时结合水平井初期裂缝监测结果、原始地层压力、生产数据验证了数值试井方法的准确性。研究结果表明:数值试井解释出的致密油水平井渗流参数准确性较高,反映的渗流规律符合国内外致密油水平井开发规律。

The tight oil horizontal wells in Daqing oilfield were generally put into production using the volumetric fracturing method. The pressure double logarithm curves showed the change in complicated boundary,physical properties or adjacent well interference and so on.The satisfactory fitting result could not be achieved by conventional well test method,and there was a big pressure error in the evaluation of dense oil horizontal well formation. Aiming at the above problems,three horizontal wells filled with dense oil in Daqing oilfield were interpreted by using the numerical well test method. From the pressure fitting curve characteristics of the 3 wells,comparing the differences in curve characteristics under varying formation conditions,the accuracy of the numerical well test method was indirectly reflected combining with the early fracture monitoring results,original formation pressure and production data of the horizontal wells,the accuracy of the numerical well test method was verified. The results showed that the flow parameters of the tight oil horizontal wells interpreted by the numerical well test method are accurate,and the flow law reflected is in line with the development rules of tight oil horizontal wells at home and abroad.