Collaborative Research: Volcanic Record in Antarctic Ice: Implications for Climatic and Eruptive History and Ice Sheet Dynamics of the South Polar Region

Dunbar/凯尔9527373 Zielinski 9527824 摘要 南极冰盖是保存火山灰（火山灰）层和火山爆发的化学气溶胶特征记录的理想场所。 这种记录既存在于裸露的蓝色冰区域，也存在于深冰芯中，包括局部喷发和来自更远火山源的喷发，其中玻璃碎片可以被化学指纹识别并与源火山有关。 1994/1995年南极考察季节在南极洲艾伦山地区进行的实地工作以及随后的微束化学分析和40 Ar/39 Ar测年表明，南极深层冰中的火山灰层保存了连贯的系统地层，可以成功地绘制地图、测定日期、确定化学特征并与源火山联系起来。 玻璃碎片的化学指纹和与灰层有关的火山气溶胶的化学分析相结合，将有助于建立本地和远程火山活动的高分辨率年表，有助于了解重大爆炸性火山活动的模式和大气负荷以及与火山爆发有关的气候影响。 在跨南极山脉的许多地方已经确定的蓝冰区中，单个火山灰层或层组的相关性将使这些地区的冰流几何形状得到更好的理解，并将为解释冰芯记录提供有用的基础。

Dunbar/Kyle OPP 9527373 Zielinski OPP 9527824 Abstract The Antarctic ice sheets are ideal places to preserve a record the volcanic ash (tephra) layers and chemical aerosol signatures of volcanic eruptions. This record, which is present both in areas of bare blue ice, as well as in deep ice cores, consists of a combination of local eruptions, as well as eruptions from more distant volcanic sources from which glassy shards can be chemically fingerprinted and related to a source volcano. Field work carried out during the 1994/1995 Antarctic field season in the Allan Hills area of Antarctica, and subsequent microbeam chemical analysis and 40Ar/39Ar dating has shown that tephra layers in deep Antarctic ice preserve a coherent, systematic stratigraphy, and can be successfully mapped, dated, chemically fingerprinted and tied to source volcanoes. The combination of chemical fingerprinting of glass shards, and chemical analysis of volcanic aerosols associated with ash layers will allow establishment of a high-resolution chronology of local and distant volcanism that can help understand patterns of significant explosive volcanisms and atmospheric loading and climactic effects associated with volcanic eruptions. Correlation of individual tephra layers, or sets of layers, in blue ice areas, which have been identified in many places the Transantarctic Mountains, will allow the geometry of ice flow in these areas to be better understood and will provide a useful basis for interpreting ice core records.