CAJ | 학술논문

川东南焦石坝及其外围页岩地层地质导向钻井存在井震矛盾突出、岩屑代表性差、地质设计与实钻地层之间往往存在较大偏差等技术难点。针对上述技术难点，基于地震及邻井资料，建立了钻前地质导向模型，以预测可能钻遇的地层；在入靶前的地质导向阶段，根据随钻测井资料和录井资料，进行地层精细对比，并修正地质导向模型，调整靶点深度，确保水平井安全、高效着陆；在水平段地质导向阶段，充分利用随钻测井、气测、钻时、岩性等数据，准确判断钻头位置，并实时修正地质导向模型，以确保钻头始终处于目的层，形成了适用于该地区的页岩水平井地质导向钻井技术。该技术在焦石坝外围的JA侧钻水平井进行了应用，气层钻遇率达到100％，优质气层钻遇率85.5％，取得了良好的应用效果。现场应用表明，该页岩水平井地质导向钻井技术适用于川东南地区页岩水平井钻井，能够有效提高气层钻遇率，对国内类似页岩气区块地质导向钻井也有借鉴作用。
천동남초석패급기외위혈암지층지질도향찬정존재정진모순돌출、암설대표성차、지질설계여실찬지층지간왕왕존재교대편차등기술난점。침대상술기술난점，기우지진급린정자료，건립료찬전지질도향모형，이예측가능찬우적지층；재입파전적지질도향계단，근거수찬측정자료화록정자료，진행지층정세대비，병수정지질도향모형，조정파점심도，학보수평정안전、고효착륙；재수평단지질도향계단，충분이용수찬측정、기측、찬시、암성등수거，준학판단찬두위치，병실시수정지질도향모형，이학보찬두시종처우목적층，형성료괄용우해지구적혈암수평정지질도향찬정기술。해기술재초석패외위적JA측찬수평정진행료응용，기층찬우솔체도100％，우질기층찬우솔85.5％，취득료량호적응용효과。현장응용표명，해혈암수평정지질도향찬정기술괄용우천동남지구혈암수평정찬정，능구유효제고기층찬우솔，대국내유사혈암기구괴지질도향찬정야유차감작용。
Geosteering drilling through shale formations at Jiaoshiba and outside in Southeast Sichuan are characterized by technical difficulties such as the obvious contradiction and poor correlation between logging and seismic data ,poor representativeness of cuttings ,and larger deviation between geological de-signs and drilled formations .To solve these technical difficulties ,pre-drilling geosteering models were first established based on seismic data and offset well data to predict the formations to be drilled .At the geos-teering stage prior to entering the target ,MWD and mud logging data were used for in-depth comparison of the formations ,and subsequent modification the geosteering model and adjustment of the target depth to ensure safe and efficient landing of the horizontal well .At the geosteering stage for the horizontal section , MWD ,gas logging ,drilling time ,lithology and other data were employed to accurately determine the po-sition of the bit and correct the geosteering model in real-time to keep the bit in the target zone all the time ,which is applicable to the geosteering drilling technology of horizontal shale wells in the area .The technology was applied to the horizontal sidetracking Well JA outside Jiaoshiba . The rate of drilling through gas formations for Well JA was 100% and the high quality rate of gas formation drilling was 85 . 5% ,which showed a good application effect .The application results showed that the geosteering drilling technology is suitable for horizontal shale drilling in Southeast Sichuan .It could effectively improve the rate of gas formation drilling and could be also taken as a reference for geosteering drilling in other similar shale gas blocks in China .