川东地区下侏罗统勘探潜力评价  

Evaluation on exploration potentials of Lower Jurassic reservoirs in eastern Sichuan Basin

作　　者：邹娟[1] 金涛[1] 李雪松[2] 韦腾强 郭蕊莹 白蓉[1] Zou Juan;Jin Tao;Li Xuesong;Wei Tengqiang;Guo Ruiying;Bai Rong(Research Institute of Exploration and Development,PetroChina Southwest Oil ＆ Gas Field Company;Research Institute of Exploration and Development,PetroChina Xinjiang Oilfield Company)

机构地区：[1]中国石油西南油气田公司勘探开发研究院 [2]中国石油新疆油田公司勘探开发研究院

出　　处：《中国石油勘探》2018年第4期30-38,共9页China Petroleum Exploration

基　　金：国家科技重大专项"大型油气田及煤层气开发"(2016ZX05046)

摘　　要：川东地区多口井在侏罗系见良好的油气显示,但因区内侏罗系构造高部位已被剥蚀殆尽,一直以来都未被给予足够的重视。明确区内侏罗系的勘探潜力,对于指导川东地区侏罗系下一步勘探有重要意义。通过对烃源岩、储层、构造及保存等条件分析认为:区内下侏罗统凉高山组和大安寨段烃源岩厚度大,凉高山组有效烃源岩厚5.6~35.8m,大安寨段有效烃源岩厚2.7~58.0m;凉高山组有机碳含量为0.15%~3.86%,大安寨段有机碳含量为0.15%~2.76%,平均都在1.00%左右,有机质丰度高,处于油气生成高峰期,资源丰富;砂岩和石灰岩储层均表现出特低孔特低渗的特征,但有利储集体滩坝和介壳滩在川东中北部地区大面积分布;互层式的源储组合有利于油气短距离运移聚集成藏;褶皱带宽缓向斜区内侏罗系保存完整,油气保存条件较好。这些都反映出川东地区下侏罗统凉高山组和大安寨段具有良好的勘探潜力,其中川东中北部地区的宣汉—开江—梁平—万州一带成藏条件最优,评选出凉高山组勘探有利区面积约5000km^2、大安寨段勘探有利区面积约3000km^2。Many wells in eastern Sichuan Basin delivered good oil and gas shows in the Jurassic formation, but they have not been given enough attention due to the fact that the Jurassic structural highs were almost eroded. Therefore, identifying the exploration potential is of great significance in guiding the exploration of the Jurassic reservoirs in the eastern Sichuan Basin. The conditions of source rocks, reservoirs, structures and preservation are analyzed, and the results show that the source rocks in the Lower Jurassic Lianggaoshan Formation and Da＇anzhai Member are relatively thick, the effective source rock in the Lianggaoshan Formation is 5.6-35.8 m thick, and that in the Da＇anzhai Member is 2.7-58.0 m thick; the TOC of the Lianggaoshan Formation is 0.15% -3.86%, and that of the Da＇anzhai Member is 0.15%-2.76%, both about 1.00% on average; the high organic matter abundance indicates hydrocarbon generating is at a peak period there and the resources are rich; sandstone and limestone reservoirs are of extremely low porosity and permeability, but favorable reservoirs in beach bars and shelly beaches are distributed over a large area in the central and northern parts of the eastern Sichuan Basin; the interbedded source-reservoir assemblage is favorable for short-distance migration and accumulation of hydrocarbon; the well preserved Jurassic formation in the wide and gentle syneline of the fold belt provides good preservation conditions. All these points reflect that the Lower Jurassic Lianggaosban Formation and Da＇anzhai Member in the eastern Sichuan Basin have good exploration potentials, especially the Xuanhan-Kaijiang-Liangping-Wanzhou region has the best hydrocarbon accumulation conditions in the central and northern parts. Finally, about 5000 km^2 in the Lianggaoshan Formation and about 3000 km^2 in the Da＇anzhai Member are proposed for favorable areas for future exploration.

关 键 词：川东地区 下侏罗统 凉高山组 大安寨段 烃源岩 储层 源储组合 勘探潜力 

分 类 号：TE122.1[石油与天然气工程—油气勘探]