该团队使用锆石化学、实验和建模来推断近40亿年岩石圈流体的特征。研究限制了氧逸度、氯含量和温度,这使他们能够模拟金属的溶解度和运输,这些金属被假设是生命起源的关键。研究发现,在这段时间里,这些流体比陆地地幔氧化程度越高,它们与近地表水系统(可能是地面热液池)相互作用,在吸引生物前分子合成或持续微生物活动的位置放大氧化还原梯度。
据悉,人们对早期地球内高温岩石圈流体的性质知之甚少,然而许多生命起源的设想取决于它们的特性。这些流体代表了地球内部和热液池之间的关键通信途径。
附:英文原文
Title: Relatively oxidized fluids fed Earth’s earliest hydrothermal systems
Author: Dustin Trail, Thomas M. McCollom
Issue&Volume: 2023-02-10
Abstract: The properties of high-temperature lithospheric fluids within the early Earth are poorly known, yet many origin-of-life scenarios depend upon their characteristics. These fluids represent a key communication pathway between Earth’s interior and hydrothermal pools. We use zircon chemistry, experiments, and modeling to infer the character of lithospheric fluids approaching 4 billion years. We constrain oxygen fugacity, chlorine content, and temperature, which allow us to model the solubility and transport of metals that are hypothesized to be crucial for the origin of life. We show that these fluids were more oxidized than the terrestrial mantle during this time and that they were interacting with near-surface aqueous systems, possibly subaerial hydrothermal pools, amplifying redox gradients in a location attractive for prebiotic molecular synthesis or sustained microbial activity.
DOI: adc8751
Source: https://www.science.org/doi/10.1126/science.adc8751