基于经济效益评价的页岩油水平井加密调整参数优化--以鄂尔多斯盆地XAB油田长7页岩油藏为例  

Optimization of infill adjustment parameters of horizontal shale oil wells based on economic benefit evaluation:a case study of shale oil reservoir in the seventh member of Yanchang Formation in XAB Oilfield,Ordos Basin

作　　者：杨晋玉 陈晓平[2] 李超[1] 郑奎[1] 张宝娟[3] 陈春恒 Yang Jinyu;Chen Xiaoping;Li Chao;Zheng Kui;Zhang Baojuan;Chen Chunheng(No.6 Oil Production Plant,PetroChina Changqing Oilfield Company;PetroChina Planning&Engineering Institute;Research Institute of Exploration&Development,PetroChina Changqing Oilfield Company)

机构地区：[1]中国石油长庆油田公司第六采油厂 [2]中国石油天然气股份有限公司规划总院 [3]中国石油长庆油田公司勘探开发研究院

出　　处：《中国石油勘探》2023年第4期129-138,共10页China Petroleum Exploration

基　　金：国家科技重大专项“鄂尔多斯盆地致密油开发示范工程”(2017ZX05069);中国石油天然气股份有限公司重大科技专项“长庆油田5000万吨持续高效稳产关键技术研究与应用”(2016E-05-02)。

摘　　要：鄂尔多斯盆地XAB油田位于陕西省定边县境内,主要目的层为上三叠统延长组长7段,长7页岩油藏储层致密,且广泛发育高角度天然裂缝。该页岩油藏自2011年以来采用水平井滚动建产和开发,存在采出程度低和采油速度低的问题。近年来,为探索页岩油高效开发方式,在水平井开发区开展井间加密调整试验,取得较好的增油效果。根据前期加密调整试验认识,在充分考虑研究区天然裂缝特征的基础上,建立“基质—裂缝”双重介质数值模型,对不同生产年限的水平井开发区开展加密调整参数优化研究,研究的主要参数为加密时机、布缝方式、水平井井距和水力裂缝半长。共设计76套加密调整方案,模拟计算评价期内各方案累计产油量,利用财务现金流方法,计算不同方案的财务净现值率并排序优选出具有经济效益的方案。研究结果表明:(1)随着水平井区生产年限的延长,在水平井井间进行加密的效果会减弱。(2)水平井交错布缝方式要优于对称布缝方式。(3)不同加密时机条件下,最优加密调整参数也不相同:加密时机为2~10年时,最优加密井距为260m,最优水力裂缝半长为140~180m。以此为依据,对XAB油田长7页岩油藏水平井开发区开展水平井加密调整设计,加密调整后,采收率和净现值率预计分别提升1.05%和0.013,在有效改善页岩油开发效果的同时获得了良好经济效益。XAB Oilfield in Ordos Basin is located in Dingbian,Shaanxi Province.The main target layer is the shale interval in the seventh member of the Upper Triassic Yanchang Formation(Chang 7 member),with tight shale reservoir and high-angle fractures widely developed.Since 2011,rolling capacity construction and development by horizontal wells have been applied to produce the shale oil reservoir,which have the problem of low oil recovery degree and low production rate.In recent years,in order to research the high-efficiency shale oil development mode,tests of inter-well infill adjustment in horizontal well development zone have been conducted,and good results have been achieved in increasing oil production.Based on understanding of infill adjustment tests in the early stage,a“matrix-fracture”dual medium numerical model is established by fully considering the natural fracture features in the study area,and the infill adjustment parameters are optimized fo horizontal well development zones with various production years,with the main parameters including infill timing,hydraulic fracture layout,horizontal well spacing and half-length of hydraulic fractures.A total of 76 infill adjustment schemes are designed to simulate and calculate the cumulative oil production of various schemed during the evaluation period.Furthermore,the financial net present value ratio is calculated and the economically beneficial schemes are ranked and optimally selected by using the financial cash flow method.The study results show that:(1)The longer the production period of the horizontal well development zone,the poorer results of infill wells.(2)The staggered layout pattern is better than the symmetrical layout pattern of hydraulic fractures.(3)The optimal infill adjustment parameters vary given the different infill timings.When the infill timing is 2-10 years,the optimal infill well spacing is 260 m,and the optimal half-length of the hydraulic fracture ranges in 140-180 m.On this basis,the horizontal infill adjustment design for Chang 7 membe

关 键 词：鄂尔多斯盆地 长7页岩油藏 页岩油 水平井 天然裂缝特征 加密调整 加密时机 交错布缝 参数优化 经济效益 

分 类 号：TE313.4[石油与天然气工程—油气田开发工程]