四川盆地涪陵气田白马区块效益开发实践与对策

Beneficial development practice and countermeasures of Baima block in Fuling shale gas field, Sichuan Basin

刘超 包汉勇 万云强 甘玉青

LIU Chao BAO Hanyong WAN Yunqiang GAN Yuqing

中国石化 江汉油田分公司 勘探开发研究院, 武汉 430223

Exploration and Development Research Institute, SINOPEC Jianghan Oilfield Company, Wuhan, Hubei 430223, China

近年来，涪陵页岩气田在积极推进焦石坝等高压页岩气藏开发调整的同时，为了确保气田持续稳产能力，开发对象也向白马等复杂构造区块稳步拓展。基于白马区块构造变形强、地质条件复杂、单井产能低、开发难度大等问题，通过断裂带方解石U-Pb定年、三维应力场建模、地质工程一体化评价等技术方法，深入研究白马区块的构造变形期次、应力场分布特征、开发有利目标、开发技术对策等，取得了积极进展：提出了逆冲推覆作用力是涪陵地区海相常压页岩气藏构造变形差异的主控因素；创建了“两类6项”的开发选区评价参数体系，明确了白马向斜核部以南为效益建产最有利目标；形成了以天然裂缝发育特征为核心的差异化开发技术政策；形成了基于气井埋深、应力性质、裂缝等不同地质特征的工程工艺对策。在上述认识基础上，按照“整体部署、评建一体、平台接替”思路，2021—2022年部署实施开发井位30口，平均机械钻速提高38%，压裂施工速度提升2～3倍，单段压裂费用降至85万元，日产气量稳定在80万方，2022年年产气量达2.24亿方，基本实现了效益开发。

In recent years, while actively promoting the development and adjustment of high-pressure shale gas reservoirs such as Jiaoshiba shale gas reservoir, Fuling shale gas field has steadily expanded its development targets to Baima block and other complex structural blocks in order to ensure continuous and stable production capacity. Based on the strong structural deformation, complex geological conditions, low single-well productivity, and great development difficulty of Baima block, this paper deeply studies the tectonic deformation stages, stress field distribution characteristics, favorable targets, and development technical countermeasures of Baima block by means of fracture zone calcite U-Pb dating, three-dimensional stress field modeling, geoengineering integration evaluation and other technical methods, and has made positive progress: it is suggested that the thrust nappe force is the main controlling factor of the deformation difference of marine normal pressure shale gas reservoirs in Fuling area; the evaluation parameter system of “two categories, six items” for development area selection is established, and the south of Baima syncline core is identified as the most favorable target for beneficial development; a differentiated development technology policy based on the development characteristics of natural fractures has been formed; the engineering process countermeasures based on different geological characteristics such as gas well buried depth, stress property and crack are formed. On the basis of the above understanding, and in accordance with the idea of “overall deployment, evaluation-construction integration, and platform replacement”, 30 development well locations were deployed and implemented in 2021-2022, the average ROP was increased by 38%, the fracturing rate was increased by 2-3 times, the single stage fracturing cost was reduced to 850 000 yuan, the daily gas output was stable at 800 000 square meters, and the annual gas output reached 224 million square meters in 2022, basically realizing beneficial development.

中国石油化工股份有限公司科技项目“白马区块常压页岩气富集高产机理与目标评价”(P21087-1)资助。

https://doi.org/10.11781/sysydz2023061050