Kerogen in Archean rocks: Biotic vs abiotic signatures – Pt. II

太古宙岩石中有机质的来源是模糊的，因为各种来源（生物与非生物）都有问题。现有数据表明，大多数有机物确实是生物产生的，但后来被热液流体重新分配和隔离到不同的环境中。为了验证这一假设，我们将探讨皮尔巴拉克拉通（西澳大利亚）和巴伯顿绿岩带（南非）太古宙地层中干酪根的存在和多样性。我们将通过(i)评估其分布、体积特征和分子组成来解决这些干酪根的起源，（ii）阐明特定干酪根-矿物组合的性质，以及（iii）评估实验热成熟过程中生物与非生物有机质的地质命运。通过将各自的发现整合到一个整体模型中，我们将对太古宙早期地球的有机质性质和分布得出合理的结论。

The origin of organic matter in Archean rocks is ambiguous, as various sources come into question (biological vs abiotic). Available data suggest that most of the organic matter was indeed biologically produced, but has then been redistributed, and sequestered, into different environments by hydrothermal fluids. For testing this hypothesis, we will explore the presence and diversity of kerogens in Archean strata from the Pilbara Craton (Western Australia) and from the Barberton Greenstone Belt (South Africa). We are going to tackle the origin of these kerogens by (i) assessing their distribution, bulk characteristics and molecular composition, (ii) elucidating the nature of specific kerogen-mineral associations, and (iii) evaluating the geological fate of biological- vs abiotic organic matter during experimental thermal maturation. By integrating the respective findings into a holistic model, we will draw sound conclusions on the nature and distribution of organic matter on the early Archean Earth.