Collaborative Research: Volcanic Records from the Siple and Taylor Dome Ice Cores, Antarctica

合作研究：南极洲 Siple 和 Taylor Dome 冰芯的火山记录

• 批准号: 9614384
• 负责人: Gregory Zielinski
• 金额: $ 30.39万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-15 至 2000-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9614384&HistoricalAwards=false
• 关键词: Collaborative; Research; Volcanic; Records; Siple

9614384 Zielinski 9615167 Dunbar Abstract This award supports a project to characterize the volcanic material in the Siple Dome and Taylor Dome ice cores. The time series of volcanic aerosol and tephra deposition available in high-resolution, bi-polar ice cores is the most reliable means of developing continuous and lengthy records of past volcanic activity and assessing the climatic and environmental impact of global volcanism. The volcanic records from the Siple Dome ice core, initial ice core in the West Antarctica Ice Core Program (WAISCORES), and the Taylor Dome core, recently collected from the Transantarctic Mountains, will provide the Southern Hemisphere component of this record. These results will complement the lengthy GISP2 volcanic record from Greenland. Annual resolution should be available in the Siple Dome core for the Holocene resulting in the longest volcanic record with such resolution from Antarctica. Total length of record thought to be available from the Siple Dome core is 80,000 years whereas that for the Taylor Dome core is probably over 100,000 years. Although temporal resolution will be much coarser in the glacial portion of the Siple Dome core and in much of the Taylor Dome core, correlations and comparisons of the volcanic records from those cores with those from the GISP2 core are still possible. Evaluation of the timing of the volcanic signals in relationship to the record of changing climatic conditions available in these ice cores provides critical information on the climate forcing capabilities of global volcanism on decadal to century time scales through the Holocene. The key to developing a reliable chronology of past volcanism from the Siple Dome core is the simultaneous and continuous measurement of SO42-, a direct measure of the volcanic H2SO4 produced from the eruption, and the search for tephra in the same subsamples over the entire length of the core. The glaciochemical record will be available through other investigators in the Siple Dome project. The glaciochemical record for the Taylor Dome core is presently available. Locating tephra and identifying the source of the volcanic glass through both optical microscope and microbeam (both electron and ion microprobes) analyses will verify the source of the chemical signal and help differentiate between equatorial and local eruptions. Comparisons with the GISP2 volcanic record will assist in achieving this goal. This multiparameter approach to deciphering the volcanic record will improve on our understanding of the influence of volcanism on climate both interhemispherically and intrahemispherically. The correlation of tephra found in these cores with that found in marine sediments and in the terrestrial record will expand on the chronology of global volcanism and improve the correlation among ice core, marine, and terrestrial proxy climatic records. Visible tephra layers that should exist in the Siple Dome core and do exist in the Taylor Dome core will provide additional absolute time lines for possible correlations between the two cores, among previously collected Antarctica ice cores and with tephra studies in blue ice areas of Western Antarctica and the Transantarctic Mountains.

9614384 Zielinski 9615167 Dunbar 摘要 该奖项支持一个表征 Siple Dome 和 Taylor Dome 冰芯中火山物质特征的项目。 高分辨率双极冰芯中的火山气溶胶和火山灰沉积的时间序列是对过去火山活动进行连续和长期记录并评估全球火山活动对气候和环境影响的最可靠手段。 来自 Siple Dome 冰芯、西南极洲冰芯计划 (WAISCORES) 的初始冰芯以及最近从横贯南极山脉收集的 Taylor Dome 冰芯的火山记录将提供该记录的南半球部分。 这些结果将补充格陵兰岛漫长的 GISP2 火山记录。 Siple Dome 核心应该可以获得全新世的年度分辨率，从而产生南极洲具有此类分辨率的最长火山记录。 Siple Dome 核心的记录总长度被认为是 80,000 年，而 Taylor Dome 核心的记录可能超过 100,000 年。 尽管 Siple Dome 核心的冰川部分和 Taylor Dome 核心的大部分区域的时间分辨率会更粗糙，但这些核心的火山记录与 GISP2 核心的火山记录的关联和比较仍然是可能的。 对火山信号时间与这些冰芯中气候条件变化记录的关系进行评估，可以提供关于全新世十年至百年时间尺度上全球火山活动的气候强迫能力的关键信息。 从 Siple Dome 核心开发出过去火山活动的可靠年表的关键是同时连续测量 SO42-（对喷发产生的火山 H2SO4 的直接测量），以及在整个核心长度上的相同子样本中寻找火山灰。 冰川化学记录将通过 Siple Dome 项目的其他研究人员提供。 泰勒圆顶核心的冰川化学记录目前可用。 通过光学显微镜和微束（电子和离子微探针）分析来定位火山灰并识别火山玻璃的来源，将验证化学信号的来源，并有助于区分赤道喷发和局部喷发。 与 GISP2 火山记录的比较将有助于实现这一目标。 这种破译火山记录的多参数方法将增进我们对火山活动对半球间和半球内气候影响的理解。 这些岩心中发现的火山灰与海洋沉积物和陆地记录中发现的火山灰的相关性将扩大全球火山活动的年代学，并改善冰芯、海洋和陆地代理气候记录之间的相关性。 应该存在于 Siple Dome 核心中并且确实存在于 Taylor Dome 核心中的可见火山灰层将为两个核心之间、之前收集的南极洲冰芯以及南极洲西部和横贯南极山脉的蓝冰区域的火山灰研究之间可能的相关性提供额外的绝对时间线。