From the Himalaya to Uluru, Dr Melanie Finch explains how the greatest mountains on Earth grow

Where Anthony sees crystals and Holly sees a rock, Dr Eric Vandenberg sees atoms, and specifically, Eric counts the neutrons. Eric is a postdoc at the Adelaide University and part of the ARC Training Centre for Critical Resources for the Future, and he shrinks the solid Earth down to the subatomic scale to answer some of geology's biggest questions: how the first continents formed, how plate tectonics got started, and how the rarest metal deposits on the planet came to be. ⚛️ What even is an isotope? Same element, different number of neutrons. But some isotopes are "radiogenic" and quietly decay over geological time (hello, beta and alpha decay), and why anything heavier than lead is inherently unstable. ⏳ The gold standard for dating rocks: why uranium and thorium love hiding inside zircon crystals, why lead doesn't, and how that mismatch lets geologists measure the exact age of a rock - this is geochronology in a nutshell. 🪨 The Pilbara: older than almost anything left on Earth. A craton stretching from 3.6 to 2.8 billion years old, closer in age to the formation of the planet than to today, and one of the best-preserved windows we have into Earth's earliest crust. 🌋 Earth vs Venus: why Earth is the only planet in the solar system with true plate tectonics, what a "stagnant lid" planet like Venus looks like instead, and the decades-old scientific debate over exactly when Earth made the switch. ⛏️ From ancient cratons to critical minerals: How isotope geochemistry traces the journey of gold, copper, nickel and platinum from sulfides deep in the mantle into the porphyry and IOCG deposits we mine today, without needing the impossibly hot magmas of the early Earth. A huge thank you to the Centre for Critical Resources for the Future for supporting this episode. 🔗 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.

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 @thegeoco Thanks 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.

Pushing the frontiers of knowledge about our planet has never been so much fun! We've explored less of the ocean floor than we have the surface of Mars, so Dr Ron Hackney, director of ANZIC (the Australian New Zealand International Scientific Drilling Consortium), brought the ocean floor to us. Across three remarkable objects: a core from the fault that ruptured the 2011 Tōhoku earthquake; a set of microscopic radiolarian fossils; and the world-famous "day the dinosaurs died" core from the Gulf of Mexico; we trace what scientific ocean drilling can tell us about earthquakes, mass extinction, and life clinging on kilometres beneath the seafloor. We also hear how Ron went from an Antarctica-obsessed undergraduate to leading Australia and New Zealand's role in international ocean drilling. Thanks to the Geological Society of Australia for facilitating this episode, and so many Wonder episodes over the past couple of years.🔗 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.

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.

Critical Chromium: From Field Samples to Space Technology: How Do We Secure Supply?