摘要
海底滑坡及其触发的海啸是海洋地质灾害的重要组成部分。随着海洋工程设施及沿海地区人口及经济的快速增长,海洋地质灾害研究和评估变得越来越重要和紧迫。根据高精度地球物理资料(地震和多波束),在南海北部主要含油气盆地(珠江口盆地和琼东南盆地)中发现大量的海底滑坡。这些海底滑坡形成于上新世至第四纪,它们多以杂乱或空白的地震反射为特征,部分海底滑坡含有大量滑塌块体;这些海底滑坡的规模从数平方千米至上万平方千米不等。本文梳理了南海北部海底滑坡的特征;并对包括西沙隆起在内的海底滑坡所造成的直接灾害和次生灾害(海啸)进行初步评估;最后,指出了南海北部未来海底滑坡研究中需要解决并有望取得突破的主要科学(海底滑坡的成因机制)和实践(潜在海底滑坡及其触发海啸可能性)问题。
Submarine landslides and the tsunamis they trigger can cause catastrophic damage to the infrastructure,economy,and lives increasingly expanding on the sea and along the coastlines.Therefore,quick technological progress is needed to guard against geohazards triggered by submarine landslides.Submarine landslides are identified by a large amount of geophysical data(seismic and multibeam bathymetrical data)in the petroliferous basins(the Pearl River Mouth Basin and the Qiongdongnan Basin)along the margin of the northern South China Sea.These submarine landslides formed from the Pliocene to Quaternary periods,ranging in size from several to over ten thousand square kilometers.They are mostly characterized by chaotic and blank seismic reflections;some contain a large number of collapse blocks.The seismic characteristics,sizes,origins,and geohazard potentials of these submarine landslides vary greatly because of their different developing environments.In this study,the seismic expression of submarine landslides is characterized,and their direct and indirect geohazard potentials(including those in the Xisha Massif)are evaluated.Finally,the important scientific(formation mechanism of submarine landslide)and practical questions(possible submarine landslides and landslide-generated tsunami)arising from this research are discussed.
作者
孙启良
解习农
吴时国
SUN Qiliang;XIE Xinong;WU Shiguo(Hubei Key Laboratory of Marine Geological Resources,China University of Geosciences(Wuhan),Wuhan 430074,China;Department of Earth Science,University of Oxford,Oxford OX13AN,UK;Institute of Deep-sea Science and Engineering,Chinese Academy of Sciences,Sanya 572000,China)
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2021年第2期258-270,共13页
Earth Science Frontiers
基金
国家自然科学基金项目(41676051)。
关键词
海底滑坡
海啸
地质灾害
灾害评估
南海北部
submarine landslide
tsunami
geohazard
geohazard evaluation
northern South China Sea
