元素录井在页岩油水平井开发中的应用以吉木萨尔凹陷二叠系芦草沟组为例

Application of element logging in horizontal well development of shale oil:A case study of the Permian Lucaogou Formation in Jimsar Sag,Xinjiang,China

水平井+压裂是非常规油气资源开发的主要途径,而制约其开发效益的关键工程因素在于提高水平段的"甜点"钻遇率和优化压裂方案。以准噶尔盆地吉木萨尔凹陷芦草沟组页岩油储层为例,针对重点井进行高密度XRF扫描,得到的元素含量曲线可以较好地判别地层岩性变化,借助元素资料建立导向控制点,结合精细的地层对比框架,建立目的层的高精度三维地质模型。应用结果表明,元素录井技术有助于提高地质导向成功率。在完钻井的水平段脆性评价中,元素资料建立的脆性曲线与测井计算结果吻合较好,证实该项技术在压裂方案设计中有较好的应用前景。

Horizontal well+fracturing is the main way to develop unconventional oil and gas resources,and the key engineering factors restricting its development benefits lie in improving the dessert drilling rate and optimizing fracturing plan in horizontal section.Taking the tight oil reservoir of the Permian Lucaogou Formation in the Jimsar Sag as an example,high-density XRF scan for key wells is applied and element content curve is obtained,which can identify the lithology changes of the formation.A high-precision 3D geological model of the target layer is established through the guidance control points from the elemental data and through fine stratigraphic correlation framework.The application results show that the element logging technology is helpful to improve the success rate of geological guidance.In the evaluation of the brittleness of the horizontal section of the completion drilling,the brittleness curve established by the element data is in good agreement with the logging calculation results,which proves that this technique has a good application prospect in the design of fracturing plan.