Collaborative Research: TransArctic Paleoclimate of the Eocene

由阿克塞尔·海伯格陆生化石的主要研究人员开创的稳定同位素技术在始新世野外遗址的跨北极轨迹上得到了应用。主要研究人员将从北极东部高地（阿克塞尔·海伯格和埃尔斯米尔岛；2008年）、北极西部高地（班克斯岛；2009年）和阿拉斯加安克雷奇附近（2010年）取回化石材料。实地考察和对这些地点沉积物和植物/脊椎动物化石的分析结果将提供始新世北部高纬度古气候的全球量化。除了用于化石木材、纤维素、树脂、有机物和碳酸盐的ä13C、ä18O和äD技术之外，他们还将应用两种新的化学技术：在从纤维素中提取的苯葡萄糖酮中使用ä18O来暗示环境水的氧同位素组成，以及使用被称为甘油二烷基甘油四醚（GDGTs）的脂质生物标志物来推断土壤温度。他们预计，他们的分析将产生一个量化的有机碳循环、土壤温度、大气相对湿度、环境水源和天气模式推断，横跨全球始新世北极样带。这些分析是专门为利用北极始新世沉积物中保存异常完好的干枯树木和凋落物层的陆地有机化合物而设计的。

Funds are provided to apply the stable isotope techniques pioneered by the principal investigators for Axel Heiberg terrestrial fossils across a Trans-Arctic trajectory of Eocene field sites. The principal investigators will retrieve fossil materials from the Eastern High Arctic (Axel Heiberg and Ellesmere Island; 2008), the Western High Arctic (Banks Island; 2009), and near Anchorage, Alaska (2010). Fieldwork and the resulting analyses of sediments and plant/vertebrate fossils across these sites will provide global quantification of Eocene northern high-latitude paleoclimate. In addition to the ä13C, ä18O and äD techniques pioneered for fossil wood, cellulose, resin, organic matter and carbonate, they will apply two new chemical techniques: the use of ä18O in phenylglucosazone derived from cellulose to imply the oxygen isotope composition of environmental water, and the use of lipid biomarkers known as glycerol dialkyl glycerol tetraethers (GDGTs) to infer soil temperature. They anticipate that their analyses will yield a quantification of organismal carbon-cycling, soil temperature, atmospheric relative humidity, environmental water source and inference of weather pattern, across a global Eocene Arctic transect. These analyses are specifically designed to exploit the exceptionally well-preserved terrestrial organic compounds of the mummified trees and litter layers within Arctic Eocene sediments.