The amazing chemistry of ocean sediments with Dr Stefan Loehr

We've directly observed less than 0.001% of the seafloor — so what's really going on down there? In this episode, Dr Stefan Löhr (ARC Future Fellow at the Adelaide University, and researcher with the Centre for Critical Resources for the Future) makes the case that the ocean floor is anything but a passive dumping ground for eroded continents. This will reshape the way you view the ocean - who knew it was so dynamic! We trace marine weathering from a decades-old mystery in seawater chemistry, through the strange true nature of "clay" (and why geologists bite rocks to classify it), into the surprisingly unresolved question of whether land plants permanently changed how fast the Earth weathers. Finally we digress to discuss a rare earth element deposit in South Australia that shouldn't exist by the textbook rules, sitting on limestone that has essentially zero rare earths of its own. Turns out the answer is written in an ancient lagoon, a pH gradient, and a very long river. Supported by the ARC Centre for Critical Resources for the Future. 🔗 Find us at thegeoco.com.au📸 Instagram & TikTok: @thegeoco📰 Sign up to our newsletter: thegeoco.substack.com GeoCo connects to you from the traditional country of the Kaurna people of the Adelaide Plains, South Australia. We pay our respects to their Elders past, present, and emerging.