The amazing chemistry of ocean sediments with Dr Stefan Loehr

<p>We&#39;ve directly observed less than 0.001% of the seafloor — so what&#39;s really going on down there? In this episode, <strong>Dr Stefan Löhr</strong> (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!</p><p>We trace marine weathering from a decades-old mystery in seawater chemistry, through the strange true nature of &quot;clay&quot; (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&#39;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.</p><p>Supported by the ARC Centre for Critical Resources for the Future.</p><p>🔗 Find us at thegeoco.com.au📸 Instagram &amp; TikTok: @thegeoco📰 Sign up to our newsletter: thegeoco.substack.com</p><p>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.</p>