Distribution and chemistry of micro-inclusions in the EPICA-DML deep ice core

EPICA-DML 深冰芯中微包裹体的分布和化学成分

• 批准号: 44665348
• 负责人: Dr. Sergio H. Faria
• 金额: --
• 依托单位: Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/44665348?language=en
• 关键词: Distribution; chemistry; micro; inclusions; EPICA

Deep ice cores have been drilled in Antarctica with the aim at reconstructing the history of Earth’s climate in the last million years. However, the interpretation of paleoclimatic records is severely entangled by perennial chemical reactions, mixing and diffusion processes involving many of the valuable climate proxies confined in polar ice. Particularly critical in this respect is the formation of micro-inclusions such as “black dots” and micro-bubbles, as well as possible veins of acid solutions at triple junctions. In spite of the abundance of the former and the menace to climate records represented by the latter, very little is known about them. We propose in this project to investigate the chemistry, distribution, frequency and evolution (relaxation) of micro-inclusions throughout the more than 2.7 km long EPICA-DML deep ice core extracted from Dronning Maud Land, Antarctica. In order to accomplish this challenging task we plan to combine an automated method of optical microscopy and digital image processing for statistical investigations called microstructure mapping (μSM) with an integrated micro-chemical analysis via micro-focus Raman spectrometry (μRS) and scanning electron microscopy (cryo-SEM) coupled with energy-dispersive X-ray spectroscopy (cryo-EDS) and electron backscatter diffraction (cryo-EBSD). The results of this study shall not only resolve the question about the nature of micro-inclusions and the occurrence of liquid veins but also serve as basis for new models of diffusion of dissolved gases and ions in Antarctic ice, to be developed in the course of the investigations.

在南极洲钻取了深冰芯，目的是重建过去一百万年来地球气候的历史。然而，古气候记录的解释是严重纠缠的常年化学反应，混合和扩散过程，涉及许多有价值的气候代用品局限在极地冰。在这方面，特别关键的是形成微夹杂物，如“黑点”和微气泡，以及在三重连接处可能的酸溶液脉。尽管前者丰富，后者对气候记录构成威胁，但人们对它们知之甚少。我们建议在这个项目中，调查的化学，分布，频率和演变（松弛）的微包裹体在整个超过2.7公里长的EPICA-DML深冰芯提取从德龙宁毛德地，南极洲。为了完成这一具有挑战性的任务，我们计划结合联合收割机的光学显微镜和数字图像处理的统计调查，称为微结构映射（μSM）与集成的微化学分析，通过微焦点拉曼光谱（μRS）和扫描电子显微镜（cryo-SEM）与能量色散X射线光谱（cryo-EDS）和电子背散射衍射（cryo-EBSD）。这项研究的结果不仅将解决有关微包裹体的性质和液脉的出现的问题，而且还将作为在调查过程中开发的南极冰中溶解气体和离子扩散的新模型的基础。