南襄盆地泌阳凹陷渐新统核桃园组三Ⅲ亚段页岩油富集模式——以中部深凹带YYY1井取心段为例

Discussion on shale oil enrichment pattern in the Ⅲ submember of the third member of Oligocene Hetaoyuan Formation, Biyang Sag, Nanxiang Basin: a case study of cored interval of well YYY1 in the central deep sag zone

李志明 金芸芸 李楚雄 黄帅博 周圆圆 贾梦瑶 冷筠滢 余梦丽 徐二社 刘雅慧 刘鹏 何晋译

LI Zhiming JIN Yunyun LI Chuxiong HUANG Shuaibo ZHOU Yuanyuan JIA Mengyao LENG Junying YU Mengli XU Ershe LIU Yahui LIU Peng HE Jinyi

中国石化 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡 214126 页岩油气富集机理与高效开发全国重点实验室, 江苏 无锡 214126 中国石化 油气成藏重点实验室, 江苏 无锡 214126 中国石化 河南油田分公司 石油勘探开发研究院, 河南 南阳 473043

Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development, Wuxi, Jiangsu 214126, China SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi, Jiangsu 214126, China Research Institute of Exploration and Development, SINOPEC Henan Oilfield Company, Nanyang, Henan 473043, China

南襄盆地泌阳凹陷渐新统核桃园组核三段是我国陆相页岩油率先取得勘探突破的层系，但因多种因素影响始终未能实现规模开发。为揭示泌阳凹陷中部深凹带核三段页岩油勘探开发目标层段，以页岩油风险探井YYY1井核三Ⅲ亚段系统取心段为研究对象，充分利用系统取心段现场分析结果，结合前人研究成果，在剖析系统取心段岩相、页岩油富集层段特征基础上，明确了页岩油富集模式与首选勘探开发目标层。结果揭示：YYY1井核三Ⅲ中—下段主要发育含有机质纹层状混合质页岩、富有机质纹层状混合质页岩、含有机质纹层状长英质页岩、富有机质纹层状长英质页岩、含有机质层状长英质页岩、含有机质块状泥质粉砂岩/粉砂岩、含有机质块状细砂岩7种岩相；依据游离烃S1和油饱和指数OSI两个表征页岩油富集关键参数，结合核磁测井总孔隙度，共识别出8个页岩油富集层，单个页岩油富集层厚度介于5~20 m, 累计厚度81 m。核三Ⅲ中段发育的富集层段均受原位滞留烃和高TOC邻层运移烃贡献共同控制，具源储一体和源储共存双重富集模式；核三Ⅲ下段发育的富集层段均受原位滞留富集控制，属源储一体的富集模式。核三Ⅲ中段第二个页岩油富集层是泌阳凹陷中部深凹带核三Ⅲ亚段页岩油勘探开发的首选目标层段，这一认识为泌阳凹陷页岩油勘探开发部署提供了重要依据。

The third member of Oligocene Hetaoyuan Formation (Eh3) in Biyang Sag of Nanxiang Basin is the first strata in which a breakthrough for continental shale oil exploration is made, but scale development has not been realized due to a variety of factors. In order to reveal the target zone of shale oil exploration and development of the third member of Hetaoyuan Formation in the central deep sag zone of Biyang Sag, a case study on the cored interval of the Ⅲ submember of the third member of Hetaoyuan Formation (Eh33) from shale oil risk exploration well YYY1 is carried out. Systematic studies on the lithofacies types and the characteristics of shale oil enrichment intervals of the cored interval of Eh33 are carried out and the shale oil enrichment pattern and preferred target layers of shale oil exploration and development are defined by taking full advantage of the results of field analysis and combining with previous research results. The findings have shown that seven lithofacies types, i.e. organic laminar mixed shale, organic-rich laminar mixed shale, organic laminar felsic shale, organic-rich laminar felsic shale, organic layered felsic shale and organic massive argillaceous siltstone/siltstone, organic massive fine sandstone, are developed in the middle-lower interval of Eh33 of well YYY1. Eight shale oil enrichment intervals are identified according to two key parameters of free hydrocarbon (S1) and oil saturation index (OSI) and combining with the total porosity of nuclear magnetic logging. The thickness of a single shale oil enrichment interval is 5-20 m and the total thickness is 81 m. The shale oil enrichment intervals developed in the middle interval of Eh33 are all controlled by both in-situ retention hydrocarbon and migration hydrocarbon from the adjacent high TOC layer, with two enrichment patterns: source-reservoir integration and source-reservoir coexistence. The shale oil enrichment intervals developed in the lower interval of Eh33 are all controlled by in-situ retention hydrocarbon, with source-reservoir integration enrichment pattern. The shale oil enrichment interval in the middle interval is defined the preferred target interval for shale oil exploration and development in Eh33 in the central deep sag zone of Biyang Sag. This provides an important basis for shale oil exploration and development in Biyang Sag.

国家自然科学基金项目 42090022

https://doi.org/10.11781/sysydz202305952