顶气边水薄油层水平井随钻调整策略及实施

Strategy and implementation of adjustment while drilling for horizontal wells in thin oil reservoirs with gas cap and edge water

随着渤海油田开发的不断深入,多数油田进入高含水采油阶段,增储上产的压力越来越大。水平井因能扩大泄油面积,降低生产压差,提高单井产能和最终采收率,在海上油田得到了越来越多的应用。以J油田A 3H井为例,在着陆阶段通过随钻测井资料对目的层上方多套标志层进行精细对比分析,认为原设计着陆点位的构造深度变浅,综合考虑气油界面、避气高度、水平井长度以及工程可实施性等因素对着陆点进行设计优化,采用快速增斜法自目的层下方入层,指导水平井成功着陆。在该井水平段实施过程中,由于视地层倾角相比钻前预测变陡,结合气测、岩屑录井以及随钻地质导向等资料实时调整井轨迹,使得水平段储集层钻遇率达到95%,对于利用水平井高效开发类似复杂油气藏具有参考借鉴作用。

With the deepening development of Bohai Oilfield,most oilfields have entered the stage of high water-cut,and the pressure to increase reserves and production is increasing.Horizontal wells,functional in expanding oil drainage area,reducing production pressure difference,and improving productivity and ultimate recovery of single wells,have been increasingly used in offshore oilfields.Taking Well A 3H in J Oilfield as an example,during the landing stage,after detailed comparative analysis on multiple sets of key bed above the target layer through LWD data,the structural depth of the landing point originally designed is considered to be shallower.The landing point is designed and optimized on the overall consideration of factors including gas-oil interface,gas avoidance height,horizontal well length and engineering feasibility,and successful horizontal well landing is achieved from below the target layer by rapid slope increasing.During the implementation of the horizontal section of the well,the apparent formation dip is steeper than that predicted before drilling.The well trajectory is adjusted in real time based on the data of gas logging,cuttings logging and geosteering while drilling,which enables the drilling rate of horizontal reservoirs to reach 95%,providing a reference for the efficient development of similar complex oil and gas reservoir with horizontal wells.