近百年鸭绿江口常量元素沉积记录对物源变化的响应  

RESPONSES OF MACROELEMENTS TO PROVENANCE CHANGES LAST CENTURY IN THE YALU RIVER ESTUARY

作　　者：刘月[1] 程岩[1] 高建华[2] 张春鹏[1] 刘敬伟[1] 张亮[1] 

机构地区：[1]辽东学院城市建设学院,丹东118003 [2]南京大学海岸与海岛开发教育部重点实验室,南京210093

出　　处：《海洋地质与第四纪地质》2015年第4期39-48,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目(41271028;40976051)

摘　　要：为了解近百年来鸭绿江口常量元素的沉积记录对物源变化的响应,对采自鸭绿江西汊道的YLJ-40柱状样的21个样品进行了常量元素组成分析,为了对比的需要还测试了邻近浅海及各物源区56个表层沉积物中的常量元素。通过柱状样各层与各物源区的Q型聚类分析、常量元素的垂向变化分析及判别函数计算,表明西汊道的沉积记录分为上下2个沉积单元5个时段,这与前期的研究成果基本一致。另外,1932、1977、1983、1985、1995年发生在鸭绿江口的大洪水(或台风)在沉积记录中留有"痕迹",可以做为辅助定年时标与210 Pb测年相互印证。判别函数的分析结果证实柱状样下部单元为河流沉积,物质来源于鸭绿江;上部单元以海滩沉积为主,沉积物来自浅海或河流泥沙的再悬浮,偶有来自大洪水(或台风)等极端事件带来的鸭绿江河流沉积。In order to reveal the response of sediments to provenance changes last century in the Yalu River estuary, macroelement composition analysis was performed for 21 samples taken from the Core YLJ-40 col- lected at the west-branch of the river. For the purpose of comparison, 31 surface sediment samples taken from the adjacent shallow sea and provenance zones were also determined. Based on the results of Q cluster analysis, the vertical variation analysis of macroelements, and the discrimination function calculation for each layer of the core as well as the samples from the provenance zones, the sedimentary records of the West-branch of the Yalu river can be divided into two sedimentary units and five time intervals, which is consistent with previous studies. In addition, Floodings, most probably caused by typhoons, happened in the Yalu River estuary in 1932, 1977, 1983, 1985, and 1995 also left their footprints in the records, which can be used as supplementary dating markers to verify the 210 Pb dating data. The analysis of discrimination function further confirmed that the lower unit of the core was the fluvial deposits of the ~alu River, while the upper unit was primarily shoal deposits of the resuspended sediments in shallow sea occasionally with some river deposits from the Yalu by extreme events, such as flooding or typhoons.

关 键 词：常量元素 沉积记录 物源变化 极端事件 鸭绿江口 

分 类 号：P736.4[天文地球—海洋地质]