湖泊沉积生物硅的测定与应用:以湖光岩玛珥湖为例  

Determination and application of biogenic silica in lake sediments:An example from Huguangyan maar lake, southern China

作　　者：王文远[1] 刘嘉麒 彭平安[3] 

机构地区：[1]中国科学院地质研究所,北京100029 [2]北京大学地质系,北京100871 [3]中国科学院广州地球化学研究所有机地球化学国家重点实验室,广州510640

出　　处：《地球化学》2000年第4期327-330,共4页Geochimica

基　　金：国家自然科学重大基金项目资助!(49894170);国家自然科学基金项目资助!(49772173) ;国家杰出青年基金;中国博士后基金资助项目

摘　　要：在国外实验方法基础上 ,初步建立了湖泊沉积生物硅实验室测定方法。硅胶模拟实验表明,该方法准确可靠,沉积样品重复测试显示测量平均偏差小。利用此方法,首次分析了我国雷州半岛湖光岩玛珥湖B孔部分岩芯生物硅含量 ,结果显示 ,生物硅敏感地记录了末次冰消期古季风气候的变化,揭示了快速变化的B lling Aller d YoungerDryas气候事件 。The content of biogenic silica preserved in lacustrine sediments isa useful productivity index, which has been used in recently studies of the paleoenvironment and paleoclimate. On the basis of technique and method of a rapid wet alkaline extraction procedure from Mortlock and Froelich, a method of measurement of biogenic silica in lake sediments is developed, and it was applied tomeasure biogenic silica content in Core B from Huguangyan maar lake, southern China. The method is reliable and with a small variability. The record of biogenic silica in Maar Lake, Huguangyan reflects changes in diatom productivity in thelake and provides information regarding changes in paleoclimatic conditions. The data show the rapid climate shifts seen in central Greenland ice cores during the last deglaciation, and imply that paleoclimatic conditions were warmer and wetter from 13 6 to 11 3 ka B.P. (Blling Allerd), 10 1 to 8 3 ka B.P. when the content of biogenic silica were greater, and relatively dry and cool from 17 6 to 13 6 ka B.P., 11 3 to 10 1 ka B.P. (Younger Dryas) when that of biogenicsilica were lower. These results demonstrate that the contents of biogenic silica in lake sediments carry a valuable paleoclimatic record of changes in the low latitude continental region.

关 键 词：生物硅 古气候 替代指标 玛珥湖 湖泊沉积 

分 类 号：P532[天文地球—古生物学与地层学]