Constraining the Timing and Nature of Life's Emergence in Extrema: the Geology and Geochemistry of Akilia Island, West Greenland

地球上第一个生命的出现可以看作是在全球范围内的极端环境中发生的。详细的实地考察和地质年代学研究计划，结合稳定同位素（C、N、S）调查，用于探索西格陵兰岛南部已知最古老的海洋沉积岩，这些岩石包含了这些最早时代的记录。这些岩石有37到39亿年的历史。研究人员采用了双管齐下的方法来研究地球最早极端环境的沉积记录。首先，p。通过野外研究、变质岩石学观察和U-Pb锆石年代学调查，揭示了与岩石成因和随后的长期变质作用相关的岩石的地质背景和历史。其次，他们的研究寻找由生命引起并保存在最古老沉积物中的碳、氮和硫分馏形式的同位素示踪剂。皮。他的观点是，这两种方法结合起来，将在理解地球早期生命环境的极端方面取得进展。这项研究利用了由加州大学洛杉矶分校和项目合作者开发的新的超高分辨率质谱技术（MC-SIMS, C-GC-IRMS, LEC-SMS）来进行这些测量。有了这项工作，生物地球化学工具的数量将增加，用于探测早期生命的潜在证据及其出现的时间，在地球上发现的更古老的岩石中，以及最终从火星和木卫二等其他星球的样本中。

Stephen J. Mojzsis, T. Mark Harrison, Craig E. ManningThe emergence of the first life on Earth can be viewed as having occurred in the context of an extreme environment at the global scale. A detailed program of fieldwork and geochronological studies coupled with stable isotopic (C, N, S) investigations is used to explore the oldest known marine sedimentary rocks, from southern West Greenland, that contain a record of these earliest times. These rocks are between 3.7 and 3.9 billion years old. A two-pronged approach is taken to study the sedimentary record of Earth's earliest extreme environments. First, P. Is.' are revealing the geological context and history of the rocks related to petrogenesis and subsequent protracted metamorphism from field studies, metamorphic petrologic observations, and U-Pb zircon geochronological investigations. Second, their study searches for isotopic tracers in the form of C, N, and S fractionations induced by life and preserved in the oldest sediments. P.Is.' view is that these two approaches together will lead the advance in understanding the extremes of early environments for life on Earth. This research is utilizing new ultra-high resolution mass spectrometric techniques (MC-SIMS, C-GC-IRMS, LEC-SMS) developed by UCLA and project collaborators to make these measurements. With this work, the number of biogeochemical tools will increase in power and diversity for detecting potential evidence for early life and the timing of its appearance, in older rocks from Earth when they are found, and eventually in samples from other worlds, like Mars, and Europa.