【摘要】 水力压裂微地震监测资料处理解释的核心是微震事件反演定位,基于微震事件准确定位的裂缝成像结果可以为评价压裂施工效果、调整压裂设计和确定致密油气藏的开发方案等提供有效指导。为此,基于前人的研究成果,提出了改进的微震事件反演重定位方法。采取将常规的极化分析约束与空间约束相结合的思路,先对微震事件进行带极化分析约束的常规反演定位,再将走时残差目标函数加入空间约束项,对常规反演结果进行重定位。将常规方法和改进的方法应用于实际资料的微震事件反演定位并作裂缝成像,分别对压裂井中目的层段裂缝发育的走向、倾角、大小进行了描述,分析对比两种方法解释的裂缝形态,改进方法的成像结果成窄带状,收敛效果更好。更多还原

【Abstract】 Mircoseismic event location is the core of the data processing and interpretation in hydro-fracturing microseismic monitoring.Fracture imaging based on accurate microseismic event location can provide effective guidance for evaluating fracturing effect,adjusting fracturing design and determining the exploitation plan of tight oil and gas reservoirs.Therefore,the method of improved microseismic event relocation by using polarization analysis constraint in combination with spatial constraint is presented based on the research achievements of predecessors.The event coordinates inverted by conventional microseismic event location method constrained by polarization analysis are relocated by improved microseismic event relocation method which introduces spatial constraint term to objective function only containing travel time residual.The above methods have been applied to real data in order to locate the microseismic events which are used for fracture imaging.The fracture induced by hydro-fracturing in the target layer has respectively been characterized with strike,dip,size.Then the two interpreted fracture geometries have been analytically compared to each other.The imaging results from improved method are converged to a narrow strip more effectively than those from conventional location.更多还原