缝内二次转向压裂技术探索  

A Probe of Secondary Deflection Fracturing Treatment in Hydraulic Fractures

作　　者：杜宗和[1] 李佳琦 聂洪力[3] 

机构地区：[1]中国石油新疆油田分公司勘探公司,新疆克拉玛依834000 [2]中国石油新疆油田分公司工程技术研究院,新疆克拉玛依834000 [3]中国石油新疆油田分公司开发公司,新疆克拉玛依834000

出　　处：《新疆石油地质》2013年第3期349-353,共5页Xinjiang Petroleum Geology

摘　　要：转向重复压裂是挖掘老区低渗油藏剩余油的重要途径,目前常规转向压裂技术存在着裂缝是否转向、缝内转向方式如何以及怎样实现缝内转向等问题,最终导致裂缝转向程度不理想、压后效果不明显、压后解释不准确。在岩石力学、断裂力学、水力压裂力学基础上,结合压裂裂缝转向理论,提出了"缝内二次转向压裂"的概念,通过分析对比缝内转向压裂可能出现的4种裂缝形态,发现在水平应力差拐点处实施缝端暂堵转向压裂可最大程度沟通油藏,分析了其适用的储集层条件、关键技术,并给出初步设计方法。该技术对发展转向压裂技术体系、由经验型压裂向精细化压裂的转变具有重要的意义。Deflection re-fracturing is an important way of liberating remaining oil in low permeability reservoir in old fields. However, con- ventional deflection re-fracturing technology has many problems： whether the fracture is deflected or not？ How does the deflected fracture propagate？ How to get the fracture deflected accurately？ Finally, they genenrally cause the unsatisfactory deflecting angle, ineffective treat- ment, inaccurate effect evaluation, etc. In view of this and on the basis of rock mechanics, fracture mechanics and hydraulic fracturing me- chanics, this paper puts forward the concept of ＂secondary deflection fracturing in fractures＂, analyzes and contrasts four kinds of fracture shapes that probably appear in deflection fracturing in fractures. And it is concluded that the best deflecting position is just at the inflection point of horizontal stress difference, which can get maximum communication with reservoirs. Also, applicable reservoir conditions, key tech- niques and the preliminary design methods are presented. These techniques are of great significance for developing deflection fracturing systems and for converting empirical fracturing treatment to fine fracturing treatment.

关 键 词：转向压裂 二次转向 缝内转向 缝端封堵 水平应力差拐点 

分 类 号：TE357.1[石油与天然气工程—油气田开发工程]