Archean tectonics resembled modern-style plate tectonics? Pre-Columbia early plate tectonics in the São Francisco-Congo Craton

The geological record is known to be biased, especially for records of high- to ultra-high-pressure metamorphic rocks, which are key components for understanding one of the most fundamental questions of geoscience: how, when, and why did plate tectonics initiate on Earth? Detrital minerals can serve as proxies for tectonic and metamorphic processes, and their use help mitigate preservation bias in the geological record. Since rutile only crystallizes under pressure above 08 – 1.0 GPa, the study of detrital rutile, through the combination of trace elements, Zr-in-rutile thermometry, and U-Pb geochronology, can be used as a proxy for low temperature-pressure (T/P) metamorphic conditions through geological time. We combine new detrital rutile data from São Francisco-Congo Craton Mesoproterozoic sedimentary rocks with literature compilation to investigate T/P conditions through time and address plate tectonics evolution. Our data reveal: (i) the presence of low temperature rutile, and therefore, low T/P conditions since at least the early Archean, coexisting with intermediate T/P conditions; (ii) diversity of T/P conditions increasing from 2.1 – 1.8 Ga during the Columbia early assembly phase, and again after 0.7 Ga; (iii) average T/P conditions exhibiting marked changes through time, with lower T/P dominant in the Archean and the mid-Proterozoic. Intriguingly, this pattern stands in contrast to the higher T/P conditions determined for the mid-Proterozoic from the metamorphic bedrock record. These observations indicate that both the rutile and bedrock records are likely affected by preservation and erosional biases in different ways and should not be interpreted in isolation. The presence of low T/P since the Mesoarchean points to the presence of a tectonic regime involving low thermal gradients, most easily explained by some form of subduction.