深海沉积研究助力精准重建古海洋环境

Core Insights - The research team from the Guangzhou Institute of Geochemistry and the Qingdao Institute of Marine Geology has conducted a systematic study on deep-sea sediment cores from the western Pacific, revealing a significant upward trend in molybdenum isotope composition with increasing depth, suggesting a potential global universality of this pattern [1][4]. Group 1: Research Findings - Molybdenum (Mo) is a sensitive element to redox conditions and its isotopic composition is widely used to trace the redox history of ancient oceans, making it crucial for understanding the geological history of oceanic and atmospheric oxygen levels [1]. - The study indicates that previous assumptions about the sources and isotopic balance of molybdenum in modern oceans need reevaluation, as the focus has been primarily on iron-manganese nodules, which represent only a small fraction of oceanic sediments [1][4]. Group 2: Implications of the Study - The updated model suggests that previous research may have significantly overestimated the distribution of euxinic basins in ancient oceans, indicating that early marine environments were likely more oxygenated than previously thought, which could have facilitated the evolution and proliferation of early life [5]. - This research provides critical insights into the role of deep-sea oxidized sediments in the global molybdenum cycle and enhances the accuracy of reconstructing historical environmental changes based on geochemical indicators, contributing to a better understanding of Earth's habitability evolution and future environmental changes [5].