低渗透油藏注水诱发裂缝实验研究——以鄂尔多斯盆地吴起吴仓堡长9油藏为例  

Experimental study on waterflood induced fractures simulation in low permeability reservoir

作　　者：赵思远 贾自力 吴长辉 曲世元 洪千里 王锋[3] ZHAO Siyuan;JIA Zili;WU Changhui;QU Shiyuan;HONG Qianli;WANG Feng(Research Institute of Shaanxi Yanchang Petroleum(Group)Co., Ltd.,Xi’an 710075,China;State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China;Jingbian Oil Production Plant,Yanchang Oilfield Co., Ltd.,Shaanxi Yan’an 716000,China)

机构地区：[1]陕西延长石油(集团)有限责任公司研究院,西安710075 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]延长油田股份有限公司靖边采油厂,陕西延安718500

出　　处：《非常规油气》2021年第3期73-79,89,共8页Unconventional Oil & Gas

基　　金：国家重大专项“延安地区陆相页岩气勘探开发关键技术”(2017ZX05039)。

摘　　要：以鄂尔多斯盆地吴起吴仓堡长9岩心样品为实验介质,设计制作可模拟低渗透油藏注水诱发裂缝的实验装置。实验结果表明在恒定的注入速度下,仅当注入压力大于围压后,岩心才会产生裂缝,即有效压力才是产生诱发裂缝的必要条件。如果岩心非均质性强,分布差异变化大时,在出现多次破裂压力后才会产生诱发裂缝。与常规驱替实验对比表明,需要用起裂压力进行约束得出合理的注水倍数和注入压力,才能达到最佳的驱油效率和最大的采出程度。对于低渗透油藏,更是需要选择适度温和的注水技术政策,避免形成动态裂缝或延缓动态裂缝的延伸速度,有效扩大水驱波及体积,提高水驱采收率。The core sample of Chang 9 in Wuqi Wucangbao of Ordos Basin was taken as the experimental medium,an experimental device for simulating induced fracture induced by water injection in low permeability reservoir was designed and made.Experimental results show that,at a constant injection speed,only when the injection pressure is greater than the confining pressure,the core cracks will occur,that is,the effective pressure is the necessary condition to induce cracks.If the core heterogeneity is strong and the distribution difference is large,the induced fracture will not occur until multiple rupture pressures occur.The comparison with the conventional displacement experiments shows that reasonable injection multiples and injection pressures should be obtained by the constraint of initiation pressure to achieve the optimal displacement efficiency and maximum recovery.For low permeability reservoirs,it is necessary to choose moderate water injection technology policy,avoid the formation of dynamic fractures or delay the extension of dynamic fractures,effectively expand the swept volume of water drive,and improve the recovery rate of water drive.

关 键 词：低渗透油藏 裂缝实验 注水诱发裂缝 有效压力 

分 类 号：TE357[石油与天然气工程—油气田开发工程]