用压裂施工压力反演裂缝动态参数

INVERTING DYNAMIC PARAMETERS OF FRACTURES BY FRACTURING PRESSURE

目前 ,由于缺少直接测量水力裂缝长度及导流能力等重要参数的手段 ,而地下水力裂缝的存在总要反映到油气井压力与产量的变化上来 ,特别是压力与产量随时间的变化速度与水力裂缝的长短、导流能力的大小等参数有直接关系。在常规压裂井试井分析过程中 ,所使用的数据主要是停泵后的压降数据 ,而岩石发生破裂到停泵前这一段压裂施工压力数据则没有得到有效利用 ;同时 ,在压裂施工作业过程中也不能对裂缝的延伸状况进行动态监测。文章提供了裂缝模型的诊断技术 ,通过对岩石发生破裂到停泵前这一段压裂施工压力数据进行分析 ,确定裂缝参数随压裂时间的变化关系。这样 ,就可以实时地知道裂缝发育、发展和闭合的过程 ,对于正确指导压裂施工作业以及获得优质裂缝具有十分重要的意义。

Although there are few tools to directly measure the major parameters,such as the length and flow conductivity of the hydraulic fractures,etc ,the variation of pressure and production of oil and gas wells will reflects the existence of the hydraulic fractures Especially,the variation rate of pressure and production along with time is relative directly to the parameters, such as the length and flow conductivity of the hydraulic fractures,etc The pressure declining data after pump stop are usually used for the fracturing well test analysis However,the fracturing pressure data during the period from the rock cracking to the pump stop are not utilized effectively Also,the fracture extending state can't be dynamically monitored in the fracturing process The article provides the diagnostic techniques of fracture model With the analysis of pressure data from the rock cracking to the pump stop,the relationship between the fracture parameters and the time can be determined So,the process of growth,development and close of the fractures can be recognized real timely It is very important to properly direct the fracturing job,and obtain fractures with high quality