低渗透气藏压裂水平井试井曲线特征及影响因素  

Well testing curves of fractured horizontal wells in low-permeability gas reservoirs:characteristics and influencing factors

作　　者：常宝华[1] 强小龙 杨亚涛 曹雯[1] 任超峰 袁春晖 CHANG Baohua;QIANG Xiaolong;YANG Yatao;CAO Wen;REN Chaofeng;YUAN Chunhui(PetroChina Research Institute of Petroleum Exploration and Development,Langfang,Hebei 065007,China;No.2 Gas Production Plant,PetroChina Changqing Oilfield Company Limited,Yulin,Shaanxi 719002,China;Changbei Operation Company,PetroChina Changqing Oilfield Company Limited,Xi’an,Shaanxi 710021,China)

机构地区：[1]中国石油勘探开发研究院,河北廊坊065007 [2]中国石油长庆油田公司第二采气厂,陕西榆林719002 [3]中国石油长庆油田公司长北作业分公司,陕西西安710021

出　　处：《油气井测试》2018年第2期1-6,共6页Well Testing

基　　金：国家自然科学基金"致密砂岩微纳米孔喉系统对储层含气性及气水运移的控制机理"(51704326)

摘　　要：针对低渗透气藏压裂水平井的实测试井曲线与理论曲线在流态特征及曲线形态方面存在一定差异的问题,基于数学模型绘制试井理论曲线图版,分析了水平段长度、裂缝半长及裂缝条数对试井曲线的影响,结合矿场实例探讨了实测试井曲线与理论曲线差异的原因。研究结果表明,压裂水平井流态可划分为双线性流、径向流、储层线性流、过渡流及系统径向流等5个阶段,与水平井相比,压裂水平井在第一个径向流特征段出现之前具有明显的裂缝双线性流或线性流特征段;压裂裂缝半长越大,前期线性流及裂缝径向流差异明显;水平段越长,裂缝径向流段出现越晚,后期系统径向流段一致。综合分析认为压裂液对近裂缝储层的污染和近井形成的连通缝网是导致现场实测试井曲线与理论曲线差异的主要原因。该分析为压裂水平井试井解释模型的选用提供了依据。For fractured horizontal wells in low-permeability gas reservoirs,actual curves and theoretical curves of well testing are different in flow regime and shape. Accordingly,in this paper,theoretical type curves were generated using the mathematical model to highlight the impacts of length of horizontal section,fracture half-length and number of fractures on well testing curves. Based on case studies,root causes for differences between actual curves and theoretical curves were analyzed. The study results show that flow regimes in fractured horizontal well can be classified into 5 stages： bilinear flow,radial flow,reservoir linear flow,transitional flow and system radial flow. Compared with conventional horizontal wells,fractured horizontal wells display clear features of fracture bilinear flow or linear flow before the characteristics of the first radial flow are observed. Moreover,the longer the fracture half-length is,the more apparent the differences in initial linear flow and fracture radial flow are; the longer the horizontal section is,the later the fracture radial flow occurs,while system radial flow displays uniform regime in the late stage. In conclusion,contamination of near-fracture reservoir by fracturing fluids and inter-connected fracture networks formed in near-wellbore zones are key causes for differences between actual curves and theoretical curves of well testing. The result can provide an evidence for selection of the optimal model for interpretation of well testing data in horizontal wells.

关 键 词：低渗透气藏 压裂水平井 试井解释 流态 裂缝半长 水平段长度 表皮系数 实例分析 

分 类 号：TE353[石油与天然气工程—油气田开发工程]