摘要
在南海西北部首次发现中建南峡谷群,目前对其地质信息尚未开展相关研究.综合利用水深地形数据和二维多道地震资料,主要分析中建南峡谷群的地形地貌特征、平面展布与分段性特点,精细刻画峡谷沉积充填结构及演化特征,再进一步讨论峡谷形成的控制因素.中建南海底峡谷群分布于中建阶地与中建北海台之间,它是由西侧的一条主轴峡谷和东侧的多条小型分支峡谷组成,整体呈SE-S-SE走向,以走向转折拐点为起点,将峡谷分为三段式:北段、中段和南段,北段以侵蚀作用为主,中段和南段主要受侵蚀作用、沉积作用,东南部的峡谷口外主要受沉积作用.研究区晚中新世-第四纪时广泛分布峡谷沉积体系,包括半深海相、三角洲相、峡谷/水道充填相、滑塌相、块体搬运复合沉积和浊积扇相.揭示了该海底峡谷群的发育和演化主要受海平面变化、沉积物源供给和重力流、底流作用的控制.通过对该峡谷群的地形地貌和沉积演化特征的分析,将对海洋地质灾害、南海深水沉积体系研究及油气资源勘探有重要的科学意义.
The Zhongjiannan Canyons were first discovered in the northwest of the South China Sea. At present, relevant research on its geological information has not been carried out. Based on the comprehensive use of bathymetric topographic data and twodimensional multi-channel seismic data, in this paper it mainly analyzes the topographic and geomorphic characteristics, plane distribution and segmentation characteristics of the Zhongjiannan Canyons, finely describes the sedimentary evolution and filling structure characteristics of the Zhongjiannan Canyons, and then further discusses the controlling factors of the canyons formation.The Zhongjiannan submarine canyons is distributed between Zhongjian terrace and Zhongjianbei platform. It is composed of a main axis canyon in the west and several small branch canyons in the east. The overall trend is SE-S-SE. According to the trend turning point of the main canyon, the Zhongjiannan canyons are divided into three sections: north section, middle section and south section.The north section is dominated by erosion, the middle and south sections are mainly affected by erosion and sedimentation, and the area outside the canyon mouth in the southeast is mainly affected by sedimentation. Canyon sedimentary systems were widely distributed in the study area from Late Miocene to Quaternary, including semi-deep marine facies, delta facies, canyon/channel filling facies, slump facies, mass transported deposits and turbidite fan facies. It is revealed that the development and evolution of the submarine canyons are mainly controlled by sea level change, sediment source supply, gravity flow and bottom current. The analysis of the topography and sedimentary evolution characteristics of the canyons will have important scientific significance for the study of marine disaster geology, deep-water sedimentary system and oil and gas resources exploration in the South China Sea.
作者
孙美静
姚永坚
罗伟东
胡小三
周娇
徐子英
鞠东
刘杰
Sun Meijing;Yao Yongjian;Luo Weidong;Hu Xiaosan;Zhou Jiao;Xu Ziying;Ju Dong;Liu Jie(Key Laboratory of Marine Mineral Resources,Ministry of Natural Resources,Guangzhou Marine Geological Survey,Guangzhou 511458,China;Southern Marine Science and Engineering Guangdong Laboratory,Guangzhou 511458,China;Key Laboratory of Gas Hydrate,Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Guangzhou 510640,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2022年第11期4005-4019,共15页
Earth Science
基金
南方海洋科学与工程广东省实验室(广州)重大专项(No.GML2019ZD0207)
广东省促进经济发展专项基金(海洋经济发展用途)项目(Nos.GDNRC[2020]047,GDNRC[2021]58)
国家自然科学基金项目(No.U20A20100)
中国地质调查局项目(Nos.DD20221712,DD20221719,DD20160138)。
关键词
沉积特征
地形地貌
控制因素
中建南峡谷
南海西北部
沉积学
sedimentary characteristics
topography
control factor
Zhongjiannan canyons
Northwestern South China Sea
sedimentology
