Core Viewpoint - The research published in Nature reveals a two-billion-year transitional oxygenation process of the Earth's surface, providing crucial environmental context for understanding the origin and evolution of life on Earth, as well as the formation of sedimentary minerals and hydrocarbons [2][3]. Group 1: Research Findings - The study indicates that the Earth's atmospheric oxygen levels reached modern levels only in the late stages of Earth's history, following a gradual oxygenation process that lasted approximately two billion years [5]. - The research team utilized widely available carbonate-bound sulfate with triple oxygen isotopes (Δ′O) to trace the evolution of atmospheric oxygen content, marking a significant advancement in understanding this transition [5]. - The findings confirm that atmospheric oxygen levels reached modern levels around 410 million years ago, illustrating a phased evolution from anoxic to oxic conditions [5]. Group 2: Implications for Oil and Gas Exploration - This research provides a foundational understanding of the anomalous carbon isotope records from the Neoproterozoic to early Paleozoic eras and the complex evolution of eukaryotic life [6]. - Importantly, the study suggests the existence of a super-sized dissolved organic carbon reservoir in the ancient oceans, which may serve as a new organic carbon source for the formation of ancient oil and gas resources, offering new insights for deep and ultra-deep oil and gas exploration [6].

在沉积碳酸盐岩内，微量硫酸根中的叁氧同位素可以连续记录大气氧独有的非质量依赖氧同位素负异常 信号，进而追踪古大气氧含量的变化。 地球大气氧含量是如何从无到有达到富氧状态，并驱动生命起源演化、改善行星宜居性的？记者8月27 日从南京大学获悉，该校研究人员携手中外科研机构同行，通过建立高分辨率硫酸盐叁氧同位素数据记 录，结合系统生物地球化学模型定量分析，揭示了地球大气由无氧向富氧转变的阶段性演化历史和控制 机制。该研究为理解地球生命起源与演化和地球宜居性的形成与演化，提供了关键的地球化学示踪指标 和重要的理论基础。相关成果发表在国际学术期刊《自然》上。 研究团队通过系统采样分析与文献数据整合，建立了过去近30亿年的叁氧同位素演化记录。记录显示， 大气氧含量经历了3次显著跃迁，分别发生在古元古代（24亿年前至21亿年前）、新元古代（约10亿年 前）和古生代（约4.4亿年前）。这3次跃迁中，地球氧气从无到有，并呈阶段性上升，于距今约4.1亿年 前趋近稳定的富氧状态。 进一步研究发现，大气氧含量上升后，开始周期性氧化以缺氧为主的海洋，促进了缺氧水体中有机碳与 还原性硫的氧化，生成大量缺失34S/17O/13C的硫酸盐与 ...