The approximately 2,220–2,060 million years old Lomagundi–Jatuli Event was the longest positive carbon isotope excursion in Earth history and is traditionally interpreted to reflect an increased organic carbon burial and a transient rise in atmospheric O₂. However, it is widely held that O₂ levels collapsed for more than a billion years after this. Here we show that black shales postdating the Lomagundi–Jatuli Event from the approximately 2,000 million years old Zaonega Formation contain the highest redox-sensitive trace metal concentrations reported in sediments deposited before the Neoproterozoic (maximum concentrations of Mo = 1,009 μg g⁻¹, U = 238 μg g⁻¹ and Re = 516 ng g⁻¹). This unit also contains the most positive Precambrian shale U isotope values measured to date (maximum ²³⁸U/²³⁵U ratio of 0.79‰), which provides novel evidence that there was a transition to modern-like biogeochemical cycling during the Palaeoproterozoic. Although these records do not preclude a return to anoxia during the Palaeoproterozoic, they uniquely suggest that the oceans remained well-oxygenated millions of years after the termination of the Lomagundi–Jatuli Event.

约有2220-20.60亿年的洛马贡第—贾图利事件是地球历史上最长的正碳同位素偏移，传统上被解释为反映了有机碳埋藏的增加和大气O ₂的短暂升高。然而，普遍认为，此后O _2的水平崩溃超过十亿年。在这里，我们显示了Lomagundi–Jatuli事件后约20亿年前的Zaonega组的黑色页岩在新元古代之前沉积的沉积物中报告的氧化还原敏感性痕量金属浓度最高（Mo的最大浓度= 1,009μgg ^-1，U = 238μgg ^-1和Re = 516 ng g ^-1）。该单元还包含迄今为止测得的最阳性的前寒武纪页岩U同位素值（最大²³⁸ U / ²³⁵ U比为0.79‰），这提供了新的证据，表明古元古代已过渡到现代生物地球化学循环。尽管这些记录并不排除在古元古代期间恢复到缺氧状态，但它们独特地表明，在洛马贡迪—贾图利事件终止后的数百万年中，海洋仍然具有充氧作用。