中国东部陆架沉积环境对末次冰盛期以来海面阶段性上升的响应  

SEA-LEVEL RISE AND SEDIMENTARY ENVIRONMENT RESPONSE IN THE EAST CHINA CONTINENTAL SHELF SINCE THE LAST GLACIAL MAXIMUM

作　　者：李广雪[1,2] 刘勇[1,2] 杨子赓[3] 

机构地区：[1]中国海洋大学海洋地球科学学院,青岛266100 [2]海底科学与探测技术教育部重点实验室,青岛266100 [3]青岛海洋地质研究所,青岛266071

出　　处：《海洋地质与第四纪地质》2009年第4期13-19,共7页Marine Geology & Quaternary Geology

基　　金：国家重点基础研究发展规划项目(2005CB422304);国家自然科学基金项目(49976013)

摘　　要：到目前,还缺乏关于大型陆架系统对全球海面变化响应的研究,5年来我们对中国东部宽阔的陆架海底进行详细制图研究,结果表明:现代中国东部陆架海底沉积环境分布与末次冰盛期以来的海面变化之间有很好的响应关系;目前的陆架海底被3个沉积体系覆盖,即低海面期的古滨带、冰消期的海侵体系和高海面期的涡漩及近岸带沉积体系;末次冰期后期以来,可区分出3个快速海面上升期和3个慢速上升期。在快速上升期,海底形成了代表海岸快速移动的混杂沉积-海侵边界层,海岸平均移动速度10～22cm/a(最大64cm/a),缓慢上升期,形成了陆架广泛分布的潮流沙脊体系,三期沙脊体系之间有继承性演化关系。Up to now, there is no study on large-scale continental shelf system response to global sea level change. In this paper, seafloor sediments in the East China Sea broad continental shelf have been researched in detail by mapping in the past five years. The results show that there is a good response relationship between distribution of modern sedimentary environment in the East China shelf and sea level change since LGM. The seafloor is covered by three sedimentary systems in modern East China shelf, which are ancient onshore zone at the phase of low sea level, transgressive system during the Last Deglaciation and eddy and offshore sedimentary system in the period of high sea level. Three rapid rising periods and slow rising periods could be distinguished after LGM. During the rapid periods, transgressive boundary layer has been formed at seafloor which represents chaotic deposit due to coastal fast-moving. The average moving velocity is 10-22 cm/a （up to 64 cm/a at maximum）. In slow rising periods, tidal ridge system which was widely distributed in the continental shelf was formed. There is obvious inheritance and evolution connection among three stages of tidal sand ridge.

关 键 词：海面变化 海侵边界层 潮流沙脊体系 中国东部陆架 

分 类 号：P736.2[天文地球—海洋地质]