摘要
随着全球油气勘探向着深层、隐蔽、非常规拓展,国内的盆地油气勘探工作也不断有新的突破,新疆准噶尔盆地玛湖致密砾岩油藏资源富集,蕴含巨大的规模建产潜力。但是影响油藏渗流能力的因素复杂多样,同时在油藏开发中面临非均质性强,"甜点"的确定和分类评价难度大,两向水平主应力之差大,水力压裂缝形成、扩展机理认识不清,成本高、地质条件复杂等困难,以地质和工程一体化为指导思想,将研究区的地质特征和生产实践紧密结合,制定了针对该类油藏的"甜点"分类评价标准,采用了密切割体积压裂方法,探索了"长水平段、密切割、小井距、大井丛、工厂化"的立体开发技术试验等,形成了一套致密砾岩储层高效开发的技术体系,取得了良好的效果。"甜点"描述精度及三维地质模型精度的提高,显著地提升了钻完井工程效率,水平段轨迹平均调整次数由5次下降为2次,油层钻遇率达到90%以上;玛131井区平均簇间距由67m降至35m,300天平均累计产量增加37.5%。
With the expansion of global oil and gas exploration toward deep,subtle and unconventional reservoirs,new breakthroughs have been made in oil and gas exploration in China.The Mahu tight conglomerate reservoirs in the Junggar Basin,Xinjiang,are rich in oil resources and have great potential for establishment of large-scale productivity.However,the factors that affect the oil fl ow capacity in reservoir are complex and diverse.Also,there are a number of challenges during the development,for example,the reservoir heterogeneity is strong,determination and classifi cation evaluation of“sweet spot”are diffi cult,the difference of horizontal principal stress between the two directions is large,the formation and extension mechanism of hydraulic fractures is unclear,the cost is high,and the geological conditions are complex.Guided by geology-engineering integration,combining the geological characteristics of the study area with the production practice,the“sweet spot”classifi cation evaluation standard for this type of reservoir has been established.By using the method of intensive volume fracturing,stereoscopic development technologies and tests of“long horizontal section,intensive segments,small well spacing,large well cluster and well factory”have been explored,forming a set of technical system for effi cient development of tight conglomerate reservoirs,and achieving good results.The improvements of accuracy in“sweet spot”description and 3D geological model have signifi cantly increased the effi ciency of drilling and completion engineering.The average number of adjustment times of horizontal section trajectory decreased from 5 times to 2.The penetration rate of oil layer reached up to more than 90%.The average cluster spacing in Ma-131 well block decreased from 67 m to 35 m.The average cumulative production increased by 37.5%in 300 days.
作者
覃建华
张景
蒋庆平
冯月丽
赵逸清
朱键
卢志远
伍顺伟
Qin Jianhua;Zhang Jing;Jiang Qingping;Feng Yueli;Zhao Yiqing;Zhu Jian;Lu Zhiyuan;Wu Shunwei(Exploration&Development Research Institute,PetroChina Xinjiang Oilfi eld Company)
出处
《中国石油勘探》
CAS
CSCD
北大核心
2020年第2期110-119,共10页
China Petroleum Exploration
基金
国家科技重大专项“准噶尔盆地致密油开发示范工程”(2017ZX05070-001)
中国石油天然气股份有限公司科学研究与技术开发项目“新疆环玛湖高效评价及规模建产技术”(KT2018-13-02)。
关键词
致密砾岩
“甜点”分级
小井距
密切割
立体开发
tight conglomerate
sweet spot classifi cation
small well spacing
intensive segment
stereoscopic development
