Climate Change was Indicated by the Magnetic Susceptibility in Gaoling Weihe River Floodplain Near 120 Years[J]. 2007, (3): 196-200.DOI:
近120年来高陵渭河河漫滩沉积物磁化率指示的气候变化
摘要
根据史料记载以及高陵渭河河漫滩沉积物共110个样品磁化率、粒度成分的测定分析
研究了近120年来
该地区沉积物在0~4.0 m深度上磁化率变化特征。结果显示
高陵渭河河漫滩磁化率随深度具有高低变化节律
整个剖面分6个阶段
第1
3
5阶段频率磁化率值高
第2
4
6阶段频率磁化率值低;沉积物磁化率与粒度成分有较好的相关性
表现为频率磁化率值低
沉积物粒度成分细
反之则反。磁化率反映了沉积时期水动力强弱变化
第1
3
5阶段对应洪水规模大的时期
指示沉积时水位高
水量大;第2
4
6阶段对应洪水规模小的时期
指示沉积时水位低
水量小。洪水规模的变化间接反映了该地区近120年来气候的波动变化特征。
Abstract
Based on analyzing the historic literature and the grain size and the susceptibility for 110 samples in the Gaoling Weihe river floodplain
the character of magnetic susceptibility was researched whthin the depth of 4.0m near 120 years.According to the analysis some conclusions have been summarized as follows: there is a obvious change rhythm of susceptibility in the Gaoling Weihe river and the profile is divided into 6 stages
the 1st
3rd
5th frequency dependent susceptibility are higher than the 2nd
4th
6th ones.The susceptibility and sediment have a good relation
which is the frequency dependent susceptibility lower and the size of sediment thiner.On the contrary the conclusion is opposition.At the same time the frequency dependent susceptibility reflact the flood changes.The flood depth and scale of the 1st
3rd
5th are biger than the 2nd
4th
6th.The flood also show the changes of climate near 120 years.