海南岛东寨港红树林区岩芯地球化学特征及其古地震指示  

Geochemical Records and Its Paleoearthquake Significance of Core Sediments in Dongzhai Bay,Hainan Island,China

作　　者：张振克[1,2] 孟红明[1] 谢丽[1] 王秀玲[1] 张云峰[1] 余克服[2] 

机构地区：[1]南京大学地理与海洋科学学院海岸与海岛开发教育部重点实验室,江苏南京210093 [2]中国科学院南海海洋研究所边缘海地质重点实验室,广东广州510301

出　　处：《地理科学》2010年第5期777-782,共6页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(40676052;40830852);中国科学院边缘海重点实验室开放课题(MSGL0502)资助

摘　　要：地震对海岸带地貌与沉积有明显影响,1605年海南岛琼山地震造成东寨港地区发生严重陷落事件。对采自东寨港红树林区258cm柱状岩芯YBL孔进行了粒度和元素地球化学分析,发现地球化学元素含量在125cm附近有明显突变,对应于沉积相从陆向海的转变,125cm以下岩芯沉积物为暗红棕色陆相沉积,125cm以上为灰色-橄榄灰色海相粉砂沉积。推测该沉积相突变是对海南岛东寨港地震陷落事件响应,结合采样点潮位高程推测1605年琼山地震导致东寨港区域沉陷幅度至少为1.6～1.8m。Extreme earthquake in coastal region strongly changed the coastal landform and sedimentary sequences.The serious earthquake in the year of 1605 occurred at Qiongshan in the region around Puqian Bay,north-eastern Hainan Island,which was the most extensive earthquake recoded in the historical documents in South China with the seismic intensity of M7.5.This historical earthquake resulted in the land subsidence and the formation of the Dongzhai Bay.According to the sedimentary characteristics of the YBL Core and the analysis results about the grain seize and elements,the geochemical records of the historical earthquake was presented in this paper.The comprehensive analysis indicated the 1.6-1.8 meters subsidence occurred at the inner part of the Dongzhai Bay.The YBL Core near to Yeboluo Island was drilled to the buried red soils,which is the terrestrial environment before the earthquake subsidence.Rapid changes of the geochemical elements occurred at 125 cm of YBL Core and which indicated the environment changed quickly from terrestrial to marine environment.Further detailed study is needed for the analysis about the chronology,

关 键 词：历史地震 沉积突变 地震沉陷 红树林海岸 海南岛 

分 类 号：X142[环境科学与工程—环境科学]