天然气勘探与开发2025，Vol.48Issue(4)：41-49,9.DOI:10.12055/gaskk.issn.1673-3177.2025.04.004
多瑟欧盆地正花状反转构造及油气成藏
Positive flower reversal structures and hydrocarbon accumulation in Doseo Basin
摘要
Abstract
Characteristically distinct flower reversal structures are widely observed in the structural zones in the western uplift and the III and IV secondary structural zones in the eastern reversal anticline of Doseo Basin,western Central Africa.However,these structures are indefinite in types,evolution process and relation with hydrocarbon accumulation.Based on drilling,logging and seismic data,a systematic study was conducted through analyzing equilibrium profiles,structures and hydrocarbon accumulation.Results show that(i)in the Early Cretaceous Neocomian-Barremian,the basin developed as an extensional rift,with its structural configuration and scale shaped initially;(ii)the III and IV secondary structural zones in the eastern reversal anticline are flower-shaped reversal structures controlled by strike-slip faults F1 and F2,and above them are the widespread development of an unconventional positive flower reversal structures.The prominent manifestation is that the upward divergent part of the flower shaped structure is mainly composed of small normal faults,but the geological morphology presents an antiform,while the western uplift structural belt develops large conventional positive flower reversal structures;(iii)the structural zones in the western uplift develop large-scale conventional positive flower reversal structures.The basin has evolved primarily in three stages:extensional rift,strike-slip,and depression.During the depression stage,it has also undergone three episodes of structural inversion.The evolution process of positive flower reversal structures are predominantly characterized by short rifting and long depression,strong extension-strike-slip,and three episodes of impulse reversion strong in the west and weak in the west;(iv)structural reversion activities controlled the development and distribution of positive flower reversal structures and associated traps;and(v)the traps of positive flower reversal structures at the III and IV secondary structural zones in the eastern reversal anticline are categorized into inner-source and above-source hydrocarbon accumulation models,and show good matches in terms of trap-formation time,peak hydrocarbon generation and expulsion of effective source rocks,episodes of structural reversion,and fault reactivation time.关键词
中非剪切带/多瑟欧盆地/正花状反转构造/演化进程/油气成藏/生储盖组合Key words
Central African shear zone/Doseo Basin/Positive flower reversal structure/Evolution process/Hydrocarbon accumulation/Source-reservoir-cap combination分类
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张懿,郑求根..多瑟欧盆地正花状反转构造及油气成藏[J].天然气勘探与开发,2025,48(4):41-49,9.基金项目
中国石油股份有限公司前瞻性基础性项目"海外重点含油气盆地评价与勘探关键技术研究"(编号:2021DJ31). （编号:2021DJ31）
