地球学报2026，Vol.47Issue(2)：371-386,16.DOI:10.3975/cagsb.2025.070321
晚期翘倾改造型盆地沉积古物源识别
Identification of the Paleo-provenance of a Sedimentary Basin with Late Tilting Reformation:A Case Study of the Third Member of the Funing Formation in the Central Part of the Qintong Sag
摘要
Abstract
Sediment provenance analysis is a fundamental component in the study of sedimentary system distributions.The third member of the Funing Formation is a stratigraphic unit that is an important hydrocarbon exploration target.During the Dainan period,reformation of the depositional stratum because of the tilting of the basin caused a change in the geographic extent of the sedimentary basin of the third member of the Funing Formation,which changed the prototype basin and made determining the direction of sediment provenance difficult;this affects inference of the sedimentary system framework and the evaluation and deployment of exploration operations.Based on sedimentological principles and seismic stratigraphic methods,multiple methods were comprehensively used to analyze the direction of sediment provenance of the third member of the Funing Formation in the central part of the Qintong sag.The following conclusions were drawn:(1)Based on seismic and geological provenance synthesis analysis methods,a large sediment provenance from the southeastern Taizhou paleo-uplift was identified in the central part of the Qintong Sag.(2)The sediment in the central part of the Qintong Sag,controlled by the southeastern provenance during the depositional period of the third member of the Funing Formation,was identified;this large delta originated from the southeastern provenance area.The Qintong Sag was supplied by both the southeastern and northern provenances,which developed a sedimentary filling regime characterized by multiple provenances during the formation of the third member of the Funing Formation.(3)The Qintong Sag,considered to belong to a superimposed basin,was characterized by multi-stage evolution and late intense reformation:the paleo-topography and properties of the basin underwent changes,and late intense reformation resulted in the basin tilting.As a result,the eastern part of the sag subsided significantly and the depositional area of the southeastern provenance was deeply buried.In contrast,the western part of the sag was uplifted by the tilting,which led to partial denudation of the deposited stratum of the northern provenance and incomplete preservation of the sedimentary system.Additionally,the central part of the sag became a large sloping area,and progradation in the original stratum was transformed into an onlap.(4)The development area of the sedimentary subfacies of the delta front controlled by the southeastern provenance was considered to be the area possessing the most favorable conditions to host reservoir facies,and is therefore a favorable area for lithologic reservoir exploration.These new insights advance the identification of the sediment provenance of the third member of the Funing Formation in the Qintong Sag and provide a useful reference for sediment provenance analyses of the reformed and superimposed basin.关键词
沉积物源/溱潼凹陷/地震相/三角洲相/原型盆地/构造翘倾Key words
sediment provenance/Qintong Sag/seismic facies/delta facies/prototype basin/tectonic tilting分类
天文与地球科学引用本文复制引用
姜锐,刘震,朱茂林,唐建信,吴公益,伍炜..晚期翘倾改造型盆地沉积古物源识别[J].地球学报,2026,47(2):371-386,16.基金项目
本文由国家重大科技专项"岩性油气藏成藏动力、临界条件与分布模式"(编号:2011ZX05001-001-004)资助. This study was supported by National Science and Technology Major Project(No.2011ZX05001-001-004). （编号:2011ZX05001-001-004）
