摘要
冰芯记录的古气候信息常用化学和物理指标进行提取和分析。其中,冰芯电学性质是基础物理分析指标之一,具有重要研究意义。为了定量测定冰芯在交流电下的响应,介电剖面法(Dielectric Profiling,DEP)被提出并应用到现场冰芯电学性质分析中。然而,DEP测量冰芯的技术参数和方法需要针对现场条件进行探索,冰芯组分变化对测试信号的影响也未完全明晰。因而,基于控制变量方法,制作不同离子种类以及浓度梯度的人工模拟冰芯,建立了基于我国自主研建的DEP测量设备针对极地冰芯电学性质测试的方法,探究了DEP信号(电导率信号和介电常数信号)与化学离子种类、离子浓度、冰芯结晶速率、冰芯气体含量以及冰芯尘埃含量之间的关系。结果表明,DEP信号与冰芯中的H+、Cl−以及NH4+浓度呈现明显的线性关系。另外,冰芯的结晶速率的减缓、冰芯气体含量的上升、冰芯尘埃(草木灰)含量的上升会造成冰芯中DEP信号的下降。
The paleoclimate information recorded in ice cores is often extracted and analyzed based on chemical and physical indicators.The electrical properties of ice cores are among the fundamental physical indices.To quantitatively determine the responses of ice cores under alternating current power,dielectric profiling(DEP)was developed and applied to ice core analysis.However,the technical parameters of DEP equipment need to be explored further for field measurement.In addition,the electrical responses to changes in ice core composition are not yet fully understood.Therefore,we first produced artificial ice cores using different ion types and concentration gradients.Based on the DEP measurement method for artificial ice cores developed by China,a method for measuring Antarctic ice cores is developed.Next,the relationships among the DEP signal(conductivity signal and permittivity signal),chemical factors,ice core crystallization rate,ice core gas content,and ice core dust content were investigated using these ice cores.The DEP signal showed a significant linear relationship with hydrogen ions,chloride ions,and ammonium ions in the ice cores.In addition,decrease of the crystallization rate,increase of the ice core gas content,and increase of the dust content(plant ash)may cause decline of the DEP signal in Antarctic ice cores.
作者
徐思佳
李院生
安春雷
史贵涛
姜苏
马天鸣
鲁思宇
王丹赫
Xu Sijia;Li Yuansheng;An Chunlei;Shi Guitao;Jiang Su;Ma Tianming;Lu Siyu;Wang Danhe(School of Marine Science,Shanghai Ocean University,Shanghai 201306,China;Polar Research Institute of China,Shanghai 200136,China;School of Geographical Science,East China Normal University,Shanghai 200241,China;School of Ocean and Earth Science,Tongji University,Shanghai 200092,China;School College of Construction Engineering,Jilin University,Jilin 130026,China)
出处
《极地研究》
CAS
CSCD
北大核心
2020年第4期483-493,共11页
Chinese Journal of Polar Research
基金
国家重点研发计划课题(2016YFC1400302)
上海市自然科学基金项目(17ZR1433200)资助。
关键词
冰芯
电学性质
介电剖面法
化学因素
ice core
electrical property
dielectric profiling
chemical factor
