Geochemical record of subduction

**Evidence of early plate tectonics** Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Brad Peters explores what we can learn from the journey of sediments from the early Earth through the rock cycle. In this episode, we cover: •\[00:00] Introduction. •\[01:04] Geochemist Brad Peters tells us about the Marquesas Archipelago and why is it a place of interest for geologists. •\[02:42] He recounts evidence suggesting that one component of the Marquesas lavas was recycled sediment from the early Earth. •\[04:59] Peters walks us through the likely journey of this sediment from its origins to its eruption on the Marquesas Archipelago. •\[06:24] He explains what this lava tells us about the tectonic processes that were active four billion years ago. •\[07:43] Peters summarizes how this result is different than what we previously thought about the inception of plate tectonics. •\[08:19] He talks about what the results mean for the story of the early Earth. •\[09:13] He lists the caveats and limitations of the study. •\[10:09] Conclusion. About Our Guest: Brad Peters Postdoctoral researcher ETH Zurich View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2500506123 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter