威远页岩气压裂监测技术

Fracturing monitoring technology of Weiyuan shale gas reservoir

威远页岩气藏低孔隙度、极低基质渗透率,开采过程中水力压裂实时监测及解释效果不理想。系统介绍了井下微地震监测、广域电磁监测、地面微地震成像监测、测斜仪裂缝监测、直接近井筒裂缝监测以及光纤压裂工程监测等技术,通过对压裂监测技术进行对比和适应性分析,选择了适用于威远页岩气藏的微地震监测技术和广域电磁监测技术。经过实例验证,微地震监测技术和广域电磁监测技术可有效获取压裂过程裂缝起裂方向、延伸状态以及几何参数和空间展布特征等重要参数,为压裂过程实时调整施工参数、优化暂堵时机、实现套变预警等提供依据,最终提高页岩气采收率。

In order to ensure that the real-time monitoring and interpretation results of hydraulic fracturing in the process of shale gas exploitation achieve ideal results,this paper systematically introduces the technologies such as downhole microseismic monitoring,wide area electromagnetic monitoring,ground microseismic imaging monitoring,inclinometer fracture monitoring,direct near wellbore fracture monitoring,and optical fiber fracturing engineering monitoring,and compares and analyzes the adaptability of fracturing monitoring technologies.Microseismic monitoring technology and wide area electromagnetic monitoring technology suitable for Weiyuan shale gas reservoir are selected.Through example verification,micro seismic monitoring technology and wide area electromagnetic monitoring technology can effectively obtain important parameters such as fracture initiation direction,extension state,geometric parameters and spatial distribution characteristics in the fracturing process,so as to provide basis for real-time adjustment of construction parameters,optimization of temporary plugging time and realization of casing change early warning in the fracturing process.