Accumulation studies on Amundsenisen, Dronning Maud Land, Antarctica, by means of tritium, dielectric profiling and stable-isotope measurements: first results from the 1995–96 and 1996–97 field seasons
Accumulation studies on Amundsenisen, Dronning Maud Land, Antarctica, by means of tritium, dielectric profiling and stable-isotope measurements: first results from the 1995–96 and 1996–97 field seasons
复制标题
通过氚、介电剖面和稳定同位素测量对南极洲 Dronning Maud 地阿蒙森尼森的积累进行研究：1995-96 和 1996-97 野外季节的初步结果
作者：
H. Oerter;W. Graf;F. Wilhelms;A. Minikin;H. Miller
本文着重研究了1995-96年和1996-1997年在南极Dronning Maud陆地Amundsenisen采集的雪坑样品和浅雪岩芯。积雪的年代测定是基于人造氚在雪盖中的分布以及由电学测量确定的几个参考层。1964年初至1965年的地层标志是1963年3月阿贡火山喷发时释放到大气中的硫酸盐沉积；这一地层是通过介电剖面图和电导率测量检测到的：化学分析的证据仍有待观察。在阿蒙森森的十个调查地点中，1964-65年的地平线在地表以下4.1-5.7米处被发现。沉积物的累积速率为41~91 kg m~(-2)a−~(-1)，岩心的年龄可达100年。同位素含量与区域平均气温的关系可根据沿海纽梅耶尔站与海姆森菲尔氏菌之间10m深度降雪温度的测量结果来确定，其温度梯度为9.6%0K−~(1)。年累积率的时间序列没有明显的变化趋势，同位素记录有明显的上升趋势，梯度为0.1-0.2‰2H−。在10个时间序列中，有5个时间序列出现了δ1
Abstract The paper focuses on studies of snow-pit samples and shallow firn cores taken during the 1995-96 and 1996-97 field seasons at Amundsenisen, Dronning Maud Land, Antarctica. The dating of the firn is based on the artificial tritium distribution in the snow cover and on several reference horizons identified by electrical measurements. The early 1964 through 1965 horizon is marked by the deposition of sulfate released to the atmosphere during the eruption of the Agung volcano in March 1963; this horizon was detected by dielectric profiling and electrical conductivity measurements: the proof by chemical analysis has still to be seen. At the ten investigated sites on Amundsenisen the 1964-65 horizon was identified 4.1-5.7 m below the surface. The accumulation rates on Amundsenisen are 41-91kg m-2 a−1 The cores are up to 100 years old A relationship between isotope content and the mean air temperature on a regional scale can be based on measurements of firn temperature at 10 m depth at the drilling sites Between Neumayer station at the coast and Heimefrontfiella, the temperature gradient of the deuterium content is 9.6%0 K−1. South of Heimefrontfiella, on the Amundsenisen plateau, it is only 5.5‰ K−1. Time series of yearly accumulation rates show no significant trend For the isotope records a significant trend to higher values with gradients of 0.1-0.2 δ 2H‰a−1 can be seen in five of the ten time series