四川盆地东部下寒武统有效烃源岩与有利油气聚集区预测
Prediction of Lower Cambrian effective source rocks and favorable oil-gas accumulation areas in eastern Sichuan Basin
孙自明 1卞昌蓉 2孙玮 2刘光祥 1董田3
作者信息
- 1. 中国石化深部地质与资源重点实验室,北京 102206;中国石化石油勘探开发研究院,北京 100083
- 2. 中国石化石油勘探开发研究院,北京 100083
- 3. 中国地质大学(武汉),武汉 430074
- 折叠
摘要
为了评价四川盆地东部震旦系—下寒武统天然气勘探前景,在区域沉积-构造背景分析基础上,利用实测烃源岩总有机碳含量(TOC)、测井和二维地震数据,预测了下寒武统有效烃源岩;综合分析中三叠世末震旦系顶面古构造和下寒武统生烃中心分布,预测了有利油气聚集区.研究结果表明:晚震旦世至早寒武世强烈的沉积-构造分异导致在中上扬子地区形成台内断陷/裂陷槽、台内凹陷和台内凸起;四川盆地东部主要位于台内凸起,有效烃源岩厚度为50～150 m;习水—南川—石柱一带厚度小于30 m,有效烃源岩发育较差;平面上围绕四川盆地东部发育4个由裂陷槽和台内凹陷控制的烃源岩厚度中心及其对应的生烃中心,能够为震旦系—下寒武统提供充足的油气;四川盆地东部天然气勘探前景较好,川中古隆起及其围斜区是有利油气聚集区.
Abstract
To evaluate gas exploration prospect of Sinian-Lower Cambrian in eastern Sichuan Basin,the Lower Cambrian effective source rocks were predicted based on the analysis of regional sedimentary-tectonic back-ground,combined with the analysis of measured total organic carbon content(TOC)of source rocks,well logging and two-dimensional seismic data.The favorable accumulation areas for oil and gas were predicted through integra-tion with the paleo-structure of top Sinian and the distribution of Lower Cambrian hydrocarbon generation centers at the end of the Middle Triassic in eastern Sichuan Basin.The results show that the strongly sedimentary-tectonic differentiation from the Late Sinian to the Early Cambrian led to the formation of intra-platform fault depressions/rift troughs,intra-platform sags and intra-platform uplifts in the Middle-Upper Yangtze region.The eastern Sichuan Basin is mainly located in the intra-platform uplift,with an effective source rock thickness of 50-150 m.The thickness of effective source rocks in the Xishui-Nanchuan-Shizhu zone is less than 30 meters,and the degree of development is poor.From a plane view,four source rock development centers and corresponding hydrocarbon generation centers controlled by rift troughs and intra-platform sags have developed around the eastern Sichuan Basin.These centers could provide sufficient oil and gas sources for the Sinian-Lower Cambrian in the eastern Sichuan Basin.In conclusion,the eastern Sichuan Basin has a great potential for natural gas,and the central Sichuan paleo-uplift and its surrounding areas are favorable areas.
关键词
有效烃源岩/勘探前景/有利地区/下寒武统/震旦系/四川盆地东部Key words
effective source rock/exploration prospection/favorable area/Lower Cambrian/Sinian/eastern Sichuan Basin引用本文复制引用
基金项目
国家自然科学基金企业重点联合基金(U20B6001)
国家自然科学基金企业创新发展联合基金(U19B6003)
中国石化科技攻关计划(P19022-3)
中国石化科技攻关计划(P21042-2)
出版年
2024
NETL
NSTL
万方数据