南海西沙海域永乐海底峡谷形成演化过程分析  

Formation and evolution of Yongle Submarine canyon in the Xisha Sea area,South China Sea

作　　者：陈靓 刘时桥 辛卓 邢子浩 张经纬 刘亮 靳佳澎 李伟[3] 陈万利 CHEN Liang;LIU Shiqiao;XIN Zhuo;XING Zihao;ZHANG Jingwei;LIU Liang;JIN Jiapeng;LI wei;CHEN Wanli(Haikou Center of Marine Geological Survey,China Geological Survey,Haikou 571127,China;Pilot National Laboratory for Marine Science and Technology(Qingdao)Function Laboratory of Marine Geo-Resource Evaluation and Exploration,Qingdao 266071,China;Key Laboratory of Marginal Sea and Ocean Geology,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China;Institute of Deep-sea Science and Engineering,Chinese Academy of Sciences,Sanya 572000,China)

机构地区：[1]中国地质调查局海口海洋地质调查中心,海南海口571127 [2]青岛海洋科学与技术试点国家实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266071 [3]中国科学院南海海洋研究所边缘海与大洋地质重点实验室,广东广州510301 [4]中国科学院深海科学与工程研究所,海南三亚572000

出　　处：《热带海洋学报》2022年第5期89-104,共16页Journal of Tropical Oceanography

基　　金：中国地质调查局地调项目(DD20191027、ZD20220606);中国科学院边缘海与大洋地质重点实验室项目(OMG202010)。

摘　　要：远海孤立碳酸盐台地周缘发育了碳酸盐岩峡谷,对其开展研究有助于深刻理解碳酸盐碎屑沉积物的“源-汇”体系及深水油气成藏等方面。文章利用多波束测深、高分辨率二维多道地震等数据,精细刻画南海西沙海域永乐海底峡谷的地貌形态及内部充填特征,揭示该峡谷沉积演化过程,分析峡谷成因控制因素及稳定性。永乐海底峡谷形成演化可分为萌芽、汇聚和拓展3个阶段,随着演化过程的发展,峡谷规模及对沉积物输运作用增加。永乐海底峡谷形成及演化主要受古地貌隆起形成的负地形和沉积物重力流侵蚀作用影响。峡谷在第四纪以后仍有较明显的活动迹象。分析显示永乐海底峡谷是西北次海盆的重要物质输送通道,其沉积演化过程及稳定性对研究碳酸盐台地沉积物输运等深水沉积过程及岛礁工程建设具有一定参考意义。Carbonate canyons are developed around isolated carbonate platforms in offshore environment.The study of these canyons is helpful to understand the“source-to-sink”system of carbonate clastic sediments and deep water hydrocarbon accumulation.Based on the data of multi-beam bathymetric,high-resolution 2D multi-channel seismic profiles,we depicted the geomorphic features and internal filling characteristics of the Yongle Submarine Canyon in the Xisha area,South China Sea.We attempted to reveal the sedimentary evolution process of the canyon,and analyze its genetic controlling factors and stability.The evolution of Yongle Submarine Canyon can be divided into three stages:Embryonic stage,Convergence stage and Expansion stage.The development scale and sediment transportation is increasing with canyon evolution.The formation and evolution of the Yongle Submarine Canyon is mainly affected by the negative topography formed by paleogeomorphic uplift and the erosion of sediment gravity flow.There are still obvious signs of activity of the canyon after the Quaternary.The Yongle Submarine Canyon is an important material transport channel in the Northwest Sub-basin,and the analysis of its sedimentary evolution and stability carry significant implications for the study of deepwater sedimentary processes,such as carbonate platform sediment transport and island construction.

关 键 词：永乐海底峡谷 碳酸盐峡谷 侵蚀 形成演化 稳定性 

分 类 号：P737.21[天文地球—海洋地质]