SGER:Geochronology of Ross Sea Carbonates: Collaborative participation with the Italian National Antarctic Research Program CARBONANT Cruise 2002

该奖项由极地计划办公室提供，允许一名美国调查人员参加由意大利国家南极研究计划赞助的海洋地质研究巡航(CARBONANT项目)，并与意大利科学家开始一个新的合作研究项目。该项目旨在研究罗斯海第四纪至现代生物成因碳酸盐的生产和沉积。在罗斯海陆架和陆坡的几个部分发现了富含生物碳酸盐的沉积相，但这些相的含量和分布尚不完全清楚。此外，这些相的累积速率从未被记录在案。船上的工作将提供碳酸盐保存和动物含量的初步评估。海洋生物成因碳酸盐(如软体动物贝壳、有孔虫)是古气候和地质年代学信息的重要载体。在这次巡航期间收集的资料将用作罗斯海生物成因碳酸盐稳定同位素和地质年代学数据的基线。在船上工作之后，样品将在科罗拉多大学INSTAAR的氨基酸测年实验室进行分析。这个实验室将对从CARBONANT号邮轮上收集的沉积物样本中分离出来的碳酸盐贝壳化石进行氨基酸分析。氨基酸分析是一种有用的地质年代学工具，在以前的南极地质研究中只得到了有限的使用。这种分析方法可以辨别现代和距今500万年之间的化石年龄。氨基酸分析最适用于生物碳酸盐(如软体动物贝壳)。将对单壳样品进行成对的地质年代学分析，包括AMS、放射性碳和氨基酸分析。使用配对分析将能够校准罗斯海沉积物中的氨基酸消旋速率，并初步评估罗斯海底层水温。通过该项目收集的数据将与意大利研究人员共同解读。

0202911HartThis award, provided by the Office of Polar Programs, allows a US investigator to join a marine geological research cruise (the CARBONANT project) sponsored by the Italian National Antarctic Research Program and to begin a new collaborative research project with Italian scientists. The project is to study Quaternary to recent biogenic carbonate production and sedimentation in the Ross Sea. Sediment facies enriched in biogenic carbonate are known from several portions of the Ross Sea continental shelf and slope, however, the content and distribution of these facies are incompletely known. In addition, the accumulation rates for these facies have never been documented. Shipboard work will provide an initial assessment of carbonate preservation and faunal content. Marine biogenic carbonates (e.g. mollusc shells, foraminifera) are important vectors for paleoclimatic and geochronologic information. Collections made during this cruise are intended for use as baseline for Ross Sea biogenic carbonate stable isotope and geochronologic data. Following the shipboard work, samples will be analyzed in the Amino Acid Dating Laboratory at INSTAAR at the University of Colorado. This lab will perform amino acid analysis on carbonate shelly fossils isolated from sediment samples collected on the CARBONANT cruise. Amino acid analysis is a useful geochronologic tool that has received only limited use in previous Antarctic geologic studies. This analytical method can discern fossil ages between modern and 5 million years before present. Amino acid analysis is best applied to biogenic carbonate (e.g. mollusc shells). Paired geochronologic analyses will be performed on single shell specimens including AMS radiocarbon and amino acid analysis. The use of paired analyses will enable calibration of amino acid racemization rates in Ross Sea sediments and an initial assessment of Ross Sea bottom water temperatures. The data collected through this project will be interpreted jointly with Italian researchers.