海洋地质前沿2026，Vol.42Issue(8)：35-45,11.DOI:10.16028/j.1009-2722.2025.174
琼东南盆地陵水北坡走滑断裂特征及其控藏作用
Characteristics of strike-slip faults on the northern slope of Lingshui Sag in the Qiongdongnan Basin and their reservoir control effects
摘要
Abstract
The northern slope of the Lingshui Sag in the Qiongdongnan Basin develops a series of NWW-SEE trending strike-slip faults.However,previous studies have lacked systematic characterization of these structures;and their role in hydrocarbon accumulation in the middle-shallow layers remains unclear,hindering exploration progress in the shallow sequences.Based on high-resolution 3D seismic data,we conducted detailed structural in-terpretation to systematically analyze the geometric and kinematic characteristics of the southern strike-slip fault zone,with a focus on its control mechanism on hydrocarbon accumulation in the middle-shallow layers(Pliocene Yinggehai Formation-Holocene Ledong Formation).Results indicate that the southern strike-slip fault zone exhib-its a dextral left-stepping en-echelon distribution,characterized by typical transtensional features and negative flower structures as shown in cross-section.Integrated with regional tectonic evolution analysis,its main active period was determined as the Ledong Formation depositional stage(approximately 1.8 Ma).This study is the first to systematically propose that the strike-slip fault system exerts four key controls on middle-shallow hydrocarbon accumulation:① It served as the main vertical migration pathway,connecting deep-source rocks of the Yacheng-Lingshui formations,with geochemical evidence confirming its role as the core channel for upward hydrocarbon migration;② It controlled the development of various trap types,including fault blocks,fault noses,and en-echel-on anticlines on the descending side,while promoting the formation of lithologic traps by tilting;③ Associated structural fractures effectively improved the physical properties of fine-grained reservoirs,forming fractured mud-stone gas reservoirs;④ Quantitative evaluation showed that,although the faults extend to shallow depths,thick regional mudstone caprocks and high normal stress on fault surfaces jointly provided effective sealing,ensuring favorable preservation conditions.Therefore,the southern strike-slip fault zone is a key geological factor con-trolling hydrocarbon migration and accumulation in the middle-shallow layers of the northern slope of the Lingshui Sag.The overlapping segments of the fault zone integrated efficient migration,reservoir improvement,multiple trap types,and good preservation conditions,representing the most favorable targets for future hydrocar-bon exploration.This study enhanced the understanding of strike-slip fault control on hydrocarbon accumulation in the Qiongdongnan Basin and provided theoretical guidance for exploration in the middle-shallow layers of the study area.关键词
琼东南盆地/走滑断裂/成因机制/控藏作用Key words
Qiongdongnan Basin/strike-slip fault/formation mechanism/reservoir-controlling effect分类
海洋科学引用本文复制引用
王旖旎,金可洁,许可,桑亚迪,张晨,刘闯,牛华伟,周兴海,杨鹏程,张如凤,董鑫..琼东南盆地陵水北坡走滑断裂特征及其控藏作用[J].海洋地质前沿,2026,42(8):35-45,11.基金项目
中国石化集团科技项目"莺-琼盆地招商区油气成藏关键要素与目标评价"(P23001) （P23001）
中国石化集团上海海洋油气分公司科技项目"64/07区块乐东-莺歌海组沉积体系及圈闭刻画研究"(KJ-2025-01) （KJ-2025-01）
