~(210)Pb和~(137)Cs计年在湖泊沉降物年代学研究中的应用

DETERMINATION OF SEDIMENTATION RATES IN LAKE USING ~(210)Pb AND ~(137)Cs

摘要: 用低能γ谱仪和Ge(Li)γ谱仪分别测量了湖泊沉积物中放射性核素~(210)Pb 和~(137)Cs,确定了4个湖泊近代沉积物的年代。用二种方法测得滇池、洱海、鄱阳湖和连湖的平均沉降率分别为0.22cm/a和0.23 cm/a;0.20 cm/a和0.21 cm/a;0.57 cm/a和0.50 cm/a;0.15 cm/a和0.16 cm/a。

Abstract: Methods of using ~(210)Pb and ~(137)Cs radioactivity distribution to determine the sedimentationrates in lake are described. The specific radioactivities of ~(210)Pb and ~(137)Cs are measured directly byusing a low energy gamma ray spectrometer and a Ge(Li) gamma ray spectrometer, respectively.Based on the two methods, the sedimentation rates in profile of Dianchi lake, Erhai lake, Peyanglake and Lianhu Lake are in agreement with average values of 0.22 cm/a and 0.23 cm/a; 0.20cm/a and 0.21 cm/a; 0.57 cm/a and 0.50 cm/a; 0.15 cm/a and 0.16 cm/a, respectively.