牛庄洼陷官17井区沙四段页岩油自悬浮支撑剂压裂试验

Self-suspension proppant fracturing test of shale oil in the fourth member of Shahejie Formation in Guan-17 well area,Niuzhuang Sag

东营凹陷沙四段页岩油,具有资源量大、储层厚、地层压力系数高、天然裂缝和微裂隙发育等有利条件,但受埋藏深、断层发育、地层温度高等不利因素影响,施工成本高,递减快,经济效益差。为了克服常规缝网压裂技术在陆相页岩油储层的施工过程中遇到的压裂缝宽过窄、加砂困难等问题,促进沙四段页岩油的增产稳产,利用自悬浮支撑剂的自悬浮和自降阻性能,结合复杂缝网压裂工艺在牛庄洼陷G17-X10井进行了矿场试验,结果表明:与邻井GX26井相比,该井不仅施工难度降低,砂比提高一倍,用液减少30%,而且自喷采油期长达520 d,是GX26井的436%,自喷期累计产油2482 t,是GX26井722 t的344%。这一成果验证了自悬浮支撑剂压裂在提高压裂缝的有效支撑和增加页岩油井渗流体积方面的独特优势,不仅成功探索了新型压裂增产工艺,也拓宽了页岩油效益开发的技术思路。

Shale oil in the fourth member of Shahejie Formation in Dongying Depression has advantages such as large resource,thick reservoir,high formation pressure coefficient,and developed natural fractures and micro-fractures.However,that it is affected by unfavorable factors such as burial depth,development of faults and high formation temperature leads to high fracturing cost,rapid decline and poor economic benefit.In order to overcome the problems such as the narrow pressure fracture width and the difficulties during sand addition in the fracturing of the continental shale oil reservoir by the conventional fracturing technology,and promote the production of shale oil in the fourth member of Shahejie Formation,the on-site tests are conducted in Well-G17-X10 of Niuzhuang Sag with the performance of the self-suspension and self-reducing resistance properties of the selfsuspension proppant and combined with complex network fracturing technology.The results show that compared with the adjacent well,Well-GX26,Well-G17-X10 not only has lower fracturing difficulty,double sand ratio and less liquid reduced by 30%,but also has 520 days of self-injection production period,which is 436% of that of Well-GX26,and 2482 t of oil production period,which is 344% of 722 t of Well-GX26.This achievement verifies the unique advantages of self-suspension proppant in improving effective suspension of fractures and increasing seepage volume of oil wells.It not only successfully explores a new fracturing stimulation technology,but also broadens the technical idea of shale oil efficient production.