灰色关联法在欠平衡水平井地质导向钻进技术中的应用

Application of grey crrelative method to geosteering underbalanced horizontal drilling technology

NF273-平253井是大庆油田第1口挖潜扶余油层储量的全过程欠平衡水平井,在钻进过程后期出现了岩屑返回失真甚至取不到样的情况,单纯依靠地质导向技术难以精确控制轨迹走向。针对该井地质导向施工难点,探讨了在录井岩屑部分失真的情况下运用灰色关联法识别岩性、同时利用钻进过程中综合钻时和气测等信息配合地质导向施工的方法。利用该方法有效提高了该井储层的穿透率,对同类施工具有一定的借鉴意义。

NF273-P253 well is the first horizontal well based on underbalanced drilling technology in Daqing Oilfield to tap the potential reserves of Fuyu reservoir.Late in the process of drilling cuttings returned to distortion or even failed to get,it＇s very difficult to control the trajectory to penetrate 100% sand only by geosteering technology.Based on the analysis of the difficulties in geosteering,the paper discusses how to identify the lithological by the grey Ccorrelative method when cutting sample is distorted,and the utilization of ROP and gas log information during drilling operation.By comprehensively using the above method,the percentage of sand penetration is increased efficiently in NF273-P253 well,also the methods will be helpful for the same type of operations.