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].

Core Insights - The research conducted by Nanjing University and international collaborators reveals the evolutionary history and control mechanisms of Earth's atmospheric oxygen transition from anoxic to oxic conditions, providing critical geochemical indicators for understanding the origin and evolution of life on Earth and its habitability [1][2] Group 1: Research Findings - The study established a high-resolution record of sulfate triple oxygen isotopes, which can trace changes in ancient atmospheric oxygen levels [1] - The research team created a nearly 3 billion-year record of triple oxygen isotope evolution, indicating three significant transitions in atmospheric oxygen content occurring in the Paleoproterozoic (2.4 to 2.1 billion years ago), Neoproterozoic (around 1 billion years ago), and Paleozoic (around 440 million years ago) [1] - The atmospheric oxygen levels rose in stages, stabilizing at a near-oxic state approximately 410 million years ago [1] Group 2: Mechanisms of Change - Following the increase in atmospheric oxygen, there was a periodic oxidation of anoxic oceans, promoting the oxidation of organic carbon and reduced sulfur in anoxic waters, leading to significant isotopic disturbances [2] - This process rapidly consumed large amounts of oxygen through negative feedback mechanisms, inhibiting or even reversing further increases in atmospheric oxygen levels [2] - The research quantitatively reconstructed the evolutionary history of Earth's atmospheric oxygen content, revealing the dynamic coupling and co-evolution mechanisms between atmospheric and oceanic oxidation states [2]