Wonder

Volcanologist Dr Hayden Dalton (University of Melbourne) joins Holly & Anthony with the science he's bringing to a fascinating human question: exactly how many hominin species were alive at the same time, in the same place, and were they really competing for the same resources? Or... has the apparent overlap in existing timelines been an artifact of imprecise dating? Hayden reveals that scientists can now bracket ash layers to within about 800 years on rocks over a million years old, roughly a tenfold jump in precision from a couple of decades ago, and that new resolution is what makes it possible to test whether the overlap theory holds up (or not!). What an epic leap in science tech?!! Hayden walks us through the mystery of ancient 'trackways', that at over a million years old, preserves two different hominins' footprints in the same ash - proof, at least in that moment, that more than one species walked the same ground... You'll have to listen to find out what Hayden's age-dating reveals.Lastly, we pivot 360 to to Hayden's first volcanic love - kimberlites...Make sure you're following Wonder wherever you get your podcasts - and chuck that notifications bell on!Find us on Instagram @thegeocoThanks to the ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Geological Society of Australia⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ for making this episode of Wonder possible!GeoCo comes 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.

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.comGeoCo 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.