海洋地质前沿2026，Vol.42Issue(9)：1-12,12.DOI:10.16028/j.1009-2722.2025.187
琼东南盆地宝岛15凹在走滑-伸展复合作用下的地质结构特征及勘探潜力
Geological structure characteristics and exploration potential of Baodao 15 Sag in Qiongdongnan Basin under the combined action of strike-slip and extension
摘要
Abstract
In the southeastern margin of shallow water area in the Qiongdongnan Basin,a small lacustrine fault-controlled Eocene Lingtou Formation called Baodao 15 Sag which revealed that the rich petroleum in the Paleo-gene,due to the marginal sag prone to strong erosion,uneven uplift and late transformation,the geological struc-ture became more complex.During the fracture and depression period,the Lingtou Formation strata underwent in-tense tectonic deformation under the combined action of"strike-slip and extension",and seriously restricted the evaluation and exploration process of source rocks.Based on the analysis of the structure,fault characteristics,prototype basin of the Lingtou Formation and the process of tectonic deformation,the potential for petroleum ex-ploration and the favorable exploration directions were analyzed.Research shows that ① Baodao 15 Sag is trans-itioning from a double-faulted graben during the rifting period to a southern faulted and northern super-semi-faul-ted graben during the fault-controlled transition period which divided into eastern and the western tectonic zones by the central strike-slip fault.The uncoordinated tensile deformation of the eastern tectonic zone mainly occurred in the Eocene to Early Oligocene,formed a shingled slip sag system.The tensile deformation of the western tec-tonic zone mainly occurred in the Eocene,formed a domino-like small forward fault depression system;② By us-ing the trend extrapolation method to restore the erosion boundary and erosion volume,the semi-deep laculacine source rocks in the Eocene prototype basin were widely distributed in the concave area,with an average TOC of 0.2%to 14.2%and Ro of 0.6%to 1.8%,the area of mature source rocks was nearly 92 square kilometers,and the potential of crude oil resources was approximately 56 million tons;③ The reservoir and cap assemblage of the Lingshui-Yacheng Formation is well developed which resource volume of the hydrocarbon supply unit is abund-ant,the Lingtou Formation in the southern sag zone has the characteristic of"self-generation and self-storage"within the source,the two favorable zones are the next step of petroleum exploration in this area.关键词
边缘凹陷/走滑-伸展/原型盆地/构造演化/勘探潜力Key words
marginal sag/strike-slip and extension/prototype basin/tectonic evolution/exploration potential分类
海洋科学引用本文复制引用
万阳,胡雯燕,金峰,贺礼文,曾小宇..琼东南盆地宝岛15凹在走滑-伸展复合作用下的地质结构特征及勘探潜力[J].海洋地质前沿,2026,42(9):1-12,12.基金项目
中海石油(中国)有限公司"十四五"重大科技项目"复杂边缘海盆地深层-超深层油气成藏条件与成藏机制研究-莺琼盆地"(KJGG2022-0404) （中国）
