天然气工业2024，Vol.44Issue(3)：53-63,11.DOI:10.3787/j.issn.1000-0976.2024.03.004
夹层型页岩油突破及其油气地质意义
Exploration breakthrough of sandwiched shale oil in Sichuan Basin and its gas-oil geological implications:Taking Well G119H in the central Sichuan Basin as an example
摘要
Abstract
The PetroChina Southwest Oil & Gasfield Company deployed a key appraisal well G119H to explore the sandwiched shale oil in the Lianggaoshan Formation in the western Gongshanmiao area,central Sichuan Basin.Recently,the well achieved a production rate of 20 t/d oil and 0.6× 104 m3/d gas in test,recording a new breakthrough of lacustrine sandwiched shale oil in the basin.In order to further clarify the potential resources and exploration prospects of such shale oil in the Sichuan Basin,this paper investigates the Lianggaoshan Formation in terms of sedimentary geological setting,channel characteristics,high-quality reservoirs,and accumulation models,based on the geological and seismic data collected in the area where Well G119H is located.The results suggest that the Lianggaoshan Formation vertically develops multiple periods of lacustrine shales and delta front sand bodies overlapped under the setting of multi-phase lake basin migration.In western Gongshanmiao,the second member of Lianggaoshan Formation(Liang-2 Member)is characterized by shallow-water delta front sand body at the bottom.The sand body advances into the lake from southwest to northeast.In this member,distributary channel is the most favorable microfacies,and the dominant lithology is fine to medium-sized lithic sandstone,with an average porosity of 6.3％and a pore structure consisting of connected small pores-microthroats,where a high proportion of movable oil takes.The sandwiched shale oil in the Lianggaoshan Formation is widely distributed,with several positive factors such as thick source rocks(＞10 m),good physical properties of sandstone reservoirs,and favorable source-reservoir assemblage.According to preliminary evaluation,the favorable area for sandwiched shale oil in the basin is 1.38× 104 km2.Based on the existing 3D seismic data,the channel area of the Liang-2 Member is depicted to be 2 336 km2,and the sandwiched shale oil resources are estimated to be about 15×108 t.It is concluded that the exploration breakthrough by Well G119H suggests a large potential of sandwiched shale oil in the Liang-2 Member in central Sichuan Basin and further proves the solid endowment of shale oil in the Jurassic of the basin.The sandwiched shale oil in the Liang-2 Member in central Sichuan Basin is determined as a key interval of the 14th Five-Year Plan and the medium and long term incremental reserves/production.关键词
四川盆地/夹层型/页岩油/侏罗系/凉高山组/公山庙/勘探突破Key words
Sichuan Basin/Sandwiched/Shale oil/Jurassic/Lianggaoshan Formation/Gongshanmiao/Exploration breakthrough分类
能源科技引用本文复制引用
郭贵安,唐青松,蒋裕强,朱讯,方锐,周亚东,洪海涛,张连进,张新宇..夹层型页岩油突破及其油气地质意义[J].天然气工业,2024,44(3):53-63,11.基金项目
中国石油—西南石油大学创新联合体科技合作项目"四川盆地湖相页岩油成藏机理、富集规律、评价方法和预测技术研究"(编号:2020CX05). （编号:2020CX05）
