青海共和盆地干热岩压裂裂缝测斜仪监测研究

Research on Fracture Mapping with Surface Tiltmeters for “Hot Dry Rock” Stimulation in Gonghe Basin, Qinghai

周健 曾义金 陈作 张保平 徐胜强

ZHOU Jian ZENG Yijin CHEN Zuo ZHANG Baoping XU Shengqiang

中国石化石油工程技术研究院，北京 102206

Sinopec Research Institute of Petroleum Engineering, Beijing, 102206, China

为了更好地认识青海共和盆地增强型地热系统（EGS）压裂裂缝的方位和长度，指导该盆地换热井井位部署，优化压裂设计，采用地面测斜仪监测了X1井3个压裂阶段的裂缝，获得了该井3个压裂阶段形成垂直裂缝的长度和方位，并将监测结果与目的层地质特征结合，分析了共和盆地目标地层天然裂隙对裂缝复杂性的影响。研究表明，X1井目的层的天然裂隙在压裂过程中被部分激活，造成压裂裂缝的水平分量接近50%，在一定程度上提高了压裂裂缝的复杂性，从而提高了热储裂缝的换热体积。这为今后青海共和盆地干热岩井压裂优化设计和换热井井位部署提供了科学依据。

The three stages of hydraulic fracturing treatment in Well X1 were monitored from surface tilt mapping to better understand the fracture azimuth and length in the Gonghe Basin with enhanced geothermal systems (EGS), which would provide reference data in later deployment of adjacent wells and fracturing design. The fracture length and azimuth of Well X1 in the three stages of fracturing were obtained, and the mapping results were combined with geological features to analyze the impact of natural fractures on hydraulic fractures complexity in the target layers. The results demonstrated that some natural fractures are activated in the treatment and horizontal components of fractures are approximate to 50%, which will largely increase the complexity and heat transfer area of the fracture system. This research can provide a reference for fracturing optimization and the deployment of adjacent wells for geothermal development in Gonghe Basin of Qinghai Province.

国家重点研发计划课题“压裂监测与人工裂隙网络评价（编号：2018YFB1501803）”部分研究内容

https://doi.org/10.11911/syztjs.2020139