Development of a High Precision Chronostratigraphic Framework to Connect Antarctic Glacial and Climatic History with Global Proxy Records

该奖项由极地方案办公室南极地质和地球物理方案提供，支持建立南大洋和南极大陆架微化石的基本年代地层框架。南极大陆架和南大洋的年代地层数据已经发展到需要进行重大更新和整合的地步，以充分发挥它们在年龄分辨率方面的潜力，并满足未来钻探举措的要求(如ANDRILL和SHALDRIL所体现的)。ANDRILL和SHALDRIL要解决的问题在今天是相关的，对于理解南极冰盖重大变化的机制和速度至关重要。南极洲通过垂直和水平海洋环流、反照率、沿海地区古地理的冰川稳定控制和大气交换与全球系统紧密相连。为了了解冰盖如何响应和影响全球气候系统，至关重要的是我们拥有最好的工具来进行地质数据，特别是古生物数据的时间分辨率和远距离对比。对这些数据应用图形对比将有助于开发一种强大的年代地层学工具--综合标准参考剖面，它可以相对容易地管理各种复杂的地层数据集，并在亚热带到南极的纬度梯度上有很强的应用。这笔赠款支持的工作将开发高精度的年代地层学，并提供将这一单一的综合系统应用于南极钻探产生的各种类型数据的手段。主要目的是通过建立一个地层框架来服务于ANDRILL和SHALDRIL科学界，该框架将为高纬度和低纬度之间的信息传输提供通道。一支经验丰富的生物地层学家团队致力于重新考察过去30年来检索到的一些重要沉积剖面，并将其更新为现代分类学和年代地层数据库。此外，新西兰的克里斯·霍利斯和詹姆斯·克兰普顿正在进行的关于南大洋放射虫和有孔虫的平行研究结果将纳入数据库。我们为南极和南大洋记录提出的广泛的年代地层合成在大西洋也得到了SYNATLAN的反映，这为在赤道大西洋内外携带我们的合成和南极古气候信息提供了希望。Chronos项目将用来整合这一数据库和其他全球数据库。该项目将沿着纬度横断面为南大洋的印度部分编制一个综合标准参考组。硅藻、钙质超微化石、孢粉形态和有孔虫生物地层学事件将构成数据的主体。其他地层数据(磁性地层学、化学地层学、年代学)的精选输入将提高年代地层学的精度。将对照南大洋大西洋区段选定地点的记录，检验CSRS作为年代地层模型的稳健性。一旦经过测试和改进，这份CSRS将作为主要来自罗斯海的南极大陆架记录的时间位置的模板。这一办法将改善年代地层分辨率，将不同的生物地理省份连接成一个连续事件网络，将提出许多新物种以弥补过多的非正式硅藻名称，并将为从事不同数据集工作的科学家和世界不同地区的科学家之间的交流提供共同参考方案。所有这些成果都将有助于培养新的科学家。

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports development of a basic chronostratigraphic framework for microfossils from the Southern Ocean and Antarctic continental shelf. Chronostratigraphic data from the Antarctic shelf and Southern Ocean have advanced to the point where a substantial update and integration is required to realize their full potential in age resolution and to meet the demands of future drilling initiatives (as embodied in ANDRILL and SHALDRIL). Questions to be addressed by ANDRILL and SHALDRIL are pertinent today and critical to understand the mechanism and pace of significant changes in the Antarctic ice sheets. Antarctica is integrally linked to the global system through vertical and horizontal ocean circulation, albedo reflectivity, glacioeustatic control on paleogeography of coastal regions, and atmospheric exchange. In order to understand how the ice sheet has responded to, and influenced, the global climate system, it is vital that we possess the best tools for time resolution and long distance correlation of geological, and particularly paleontological, data. Application of graphic correlation to these data will enable the development of a powerful chronostratigraphic tool, the Composite Standard Reference Section (CSRS), which can manage diverse and complex stratigraphic datasets with relative ease, and have strong application across the subtropical to Antarctic latitudinal gradient. The work supported by this grant will develop a high precision chronostratigraphy and provide the means to apply this single integrated system to the diverse types of data generated by Antarctic drilling. The principal aim is to serve the ANDRILL and SHALDRIL scientific community by constructing a stratigraphic framework that will provide a conduit for information transfer between the high and low latitudes.An experienced team of biostratigraphers is committed to revisiting some of the important sedimentary sections retrieved over the past 30 years and updating them into a modern taxonomic and chronostratigraphic database. In addition, the results of parallel, on-going studies of Southern Ocean radiolarians and foraminifers by Chris Hollis and James Crampton of New Zealand will be integrated into the database. The broad chronostratigraphic synthesis we propose for Antarctic and Southern Ocean records is mirrored in the Atlantic Ocean by SYNATLAN, which offers promise to carry our synthesis and Antarctic paleoclimatic information within and beyond the equatorial Atlantic Ocean. The CHRONOS project will serve to integrate this and other global databases. This project will develop a Composite Standard Reference Section (CSRS) for the Indian sector of the Southern Ocean along a latitudinal transect. Diatom, calcareous nannofossil, palynomorph and foraminiferal biostratigraphic events will form the main body of the data. Selected input of other stratigraphic data (magnetostratigraphy, chemostratigraphy, tephrochronology) will enhance the chronostratigraphic precision. The robustness of the CSRS as a chronostratigraphic model will be tested against the records from selected sites in the Atlantic sector of the Southern Ocean. Once tested and refined, this CSRS will then serve as a template for the temporal placement of Antarctic shelf records derived largely from the Ross Sea. This approach will result in improvement in chronostratigraphic resolution, will link distinct biogeographic provinces into one network of sequential events, will propose numerous new species to remedy the plethora of informal diatom names, and will provide a common reference scheme for communication between scientists working on diverse data sets and in different parts of the world. All of these outcomes will facilitate the training of new scientists.