琼东南盆地北部地区对倾叠覆型变换带形成演化及成因分析  

Origin,evolution and genetic analysis of convergent overlapping transfer zone in northern Qiongdongnan Basin,South China Sea

作　　者：赵海涛 郭进京 刘重庆 ZHAO Haitao;GUO Jinjing;LIU Chongqing(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing City,100081,China;China University of Geosciences(Beijing),Beijing City,100083,China;School of Geology and Geomatics,Tianjin Chengjian University,Tianjin City,300384,China;College of Geoscience,China University of Petroleum(Beijing),Beijing City,102249,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]中国地质大学(北京),北京100083 [3]天津城建大学地质与测绘学院,天津300384 [4]中国石油大学(北京)地球科学学院,北京102249

出　　处：《油气地质与采收率》2020年第6期11-19,共9页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项“琼东南盆地断裂系统及其对油气成藏的控制作用研究”(2011ZX5023-004-012);国家自然科学基金项目“西秦岭北缘断裂带新生代构造变形几何学-运动学分析及构造变形演化”(41772215)。

摘　　要：为进一步认识裂陷盆地对倾叠覆型变换带形成和演化过程,根据地震反射资料和平衡剖面技术对琼东南盆地北部地区松西-松东变换带进行构造解析。结果表明,松西-松东变换带属于5号断层和6号断层之间的对倾叠覆型变换带,其发育过程可分为初始发育(始新世)、定型发育(崖城组沉积时期)、稳定发育(陵水组沉积时期)和消亡发育(三亚组沉积时期)等4个演化阶段。根据现有变换带成因理论及平衡剖面分析结果,松西-松东变换带主要是由于5号断层和6号断层分段生长作用造成的,其形成演化过程可以采用应力降低带理论进行解释。在裂陷阶段松西-松东变换带始终处于构造高部位,可同时捕集两侧凹陷生成的油气,且受应力降低带影响形成的大量次级断层及盆地抬升期间的风化剥蚀能有效改善储集性能,具有极为有利的油气成藏条件。Songxi-Songdong transfer zone in the northern Qiongdongnan Basin was analyzed with seismic reflection data and the balanced cross-section technique to understand the generation and evolution of the convergent overlapping transfer zone in rift basins.Consequently,it belongs to the convergent overlapping transfer zone between faults 5 and 6.Its evolution has gone through four tectonic stages:initial development(Eocene),stereotyped development(depositional period of Yacheng Formation),stable development(depositional period of Lingshui Formation),and extinction(depositional period of Sanya Formation).According to the existing genetic theory of transfer zones and the results of balanced cross-section analysis,it is considered that Songxi-Songdong transfer zone is generated mainly from the segmented growth of faults 5 and 6,and its generation and evolution processes can be explained by the theory of stress reduction zones.During the chasmic stage,Songxi-Songdong transfer zone is always tectonically high and can entrap and accumulate hydrocarbon generated by the sags on both sides.In addition,the storage and reservoir can be effectively enhanced by the plentiful secondary faults formed under the influence of the stress reduction zone and the weathering and erosion during the uplift stage of the basin.All these signal the extremely favorable conditions for hydrocarbon accumulation.

关 键 词：变换带 裂陷盆地 平衡剖面 断层分段生长 应力降低带 琼东南盆地 

分 类 号：TE121[石油与天然气工程—油气勘探]