Terrestrial Age Measurement of Antarctic Meteorites

该奖项支持一项测量南极陨石中的36Cl和41Ca的项目，以估计陨石的陆地年龄。这项工作是加州大学伯克利分校和劳伦斯利弗莫尔国家实验室的合作成果。当与陨石的其他化学和同位素数据相结合时，地球年龄可以推断出太阳系的历史和陨石撞击地球之前的轨道轨迹。陆地年龄对南极冰原的冰川学研究或对发现陨石的无冰区的地貌学研究也很有价值。对于冰原，它们提供了冰原在发现陨石的特定消融区域集中碎片和冰的时间估计。这些信息对冰盖的动态模型是有用的输入。对于无冰地区，陨石提供了对地貌表面古老程度的估计。结合暴露年龄，陆地年龄提供了关于目前无冰区过去冰川作用的有用信息。这项工作将产生的陆地年龄代表了对地貌学和冰川学研究的基线数据的有益投资。

Nishiizumi 9316272 This award supports a project to measure 36Cl and 41Ca in Antarctic meteorites in order to estimate terrestrial ages of the meteorites. This work is a collaborative effort between the University of California, Berkeley, and the Lawrence Livermore National Laboratory. When combined with other chemical and isotopic data on the meteorites, the terrestrial ages allow inferences about solar system history and orbital trajectories of the meteorites prior to collision with Earth. The terrestrial ages are also valuable for glaciological studies of the Antarctic ice sheet, or geomorphological studies of the ice-free areas, on which the meteorites are found. For ice sheets, they provide an estimate of the time that the ice sheet has been concentrating debris and ice in the particular ablation region in which the meteorite is found. This information is useful input to dynamic models of the ice sheet. For ice-free regions, the meteorites, provide an estimate of the antiquity of the geomorphic surface. In conjunction with exposure ages, the terrestrial ages provide useful information about past glaciation of the presently ice- free areas. The terrestrial ages that this work will produce represent a useful investment in baseline data for research in geomorphology and glaciology.