Earth is unique in the Solar System as the only planet characterised by an active plate tectonic regime. However, there is still no consensus on whether this was fully operational in the Archaean or if it did not develop until the Proterozoic. The metamorphic record offers valuable insight into this debate, since paired, high and low T/P metamorphic conditions are a hallmark of modern plate tectonics. However, much of the metamorphic rock record has either been eroded or overprinted by subsequent tectonothermal events. To address this issue, we examine the detrital rock record and evaluate the potential of rutile, a mineral that forms during subduction and deep-crustal metamorphic processes, as a proxy to track the existence of low T/P and paired metamorphism. At temperatures of 550°C, rutile is mostly stable at pressures higher than ca. 13 kbar. We use this relationship and the Zr-in-rutile thermometer to determine peak metamorphic temperatures of detrital rutile grains to track the temporal distribution of low T/P metamorphism. We have compiled a dataset of detrital metamorphic rutile from Archaean to Permian age to trace the occurrence of low and high T/P metamorphism through time. The earliest evidence of low T/P from detrital rutile is at about 2.1 Ga. This agrees with the earliest evidence of eclogite facies conditions from the rock record and it also implies that these conditions must have been more prevalent than the present rock record seems to indicate. Together, our study confirms that subduction zone low T/P metamorphism has been fully operating since at least the late Palaeoproterozoic.

地球在太阳系中是独一无二的，它是唯一以活跃的板块构造体系为特征的行星。然而，对于这是否在太古代完全运作，或者它是否直到元古代才发展，仍然没有达成共识。变质记录为这场争论提供了宝贵的见解，因为成对的、高和低 T/P 变质条件是现代板块构造的标志。然而，大部分变质岩记录已被随后的构造热事件侵蚀或覆盖。为了解决这个问题，我们检查碎屑岩石记录并评估金红石的潜力，金红石是一种在俯冲和深地壳变质过程中形成的矿物，作为跟踪低 T/P 和成对变质作用存在的代理。在 550°C 的温度下，金红石在高于约 100 摄氏度的压力下大部分是稳定的。13 千巴。我们使用这种关系和金红石中的 Zr 温度计来确定碎屑金红石晶粒的峰值变质温度，以跟踪低 T/P 变质的时间分布。我们编制了一个从太古代到二叠纪的碎屑变质金红石数据集，以追踪随着时间的推移低和高 T/P 变质作用的发生。来自碎屑金红石的低 T/P 的最早证据约为 2.1 Ga。这与岩石记录中榴辉岩相条件的最早证据一致，这也意味着这些条件肯定比目前的岩石记录似乎更为普遍表明。总之，我们的研究证实，至少从晚古元古代开始，俯冲带低 T/P 变质作用就已经充分发挥作用。