What makes a mineral a favorite? In this fun and down-to-earth episode, John and Shannon swap stories about the minerals they love most — and why. Along the way, they unpack cool crystal habits, formation environments, fieldwork memories, and the aesthetic appeal of minerals from museum specimens to muddy boots.
Shannon shares her appreciation for:
Hematite – With its metallic luster and planetary significance.
Goethite – A subtle but important iron oxide-hydroxide.
Smithsonite – Beautiful colors and a fascinating history in ore geology.
John counters with:
Ulexite – “TV rock,” with fiber-optic properties that never fail to wow.
Uraninite – A dense, radioactive reminder of geologic power and energy.
Tourmaline – A colorful, complex favorite of mineral collectors and scientists alike.
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John Leeman
Shannon Dulin
We're back from summer break - Shannon taught field camp, John travelled for work and got hailed on, and more!
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John Leeman
Shannon Dulin
This week we talk about how we power our instruments in the field and all of the weird and wonderful ways they fail. Including getting turned into charcoal by lightning!
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John Leeman
Shannon Dulin
This week we talk hail, Vesuvius, volcanic bombs, and vitrified brains.
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John Leeman
Shannon Dulin
Shannon's class took a trip to study catestrophic sedimentation... and they found it! John switched back to a Mac after 5 years. Join us for these and other exciting updates!
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John Leeman
Shannon Dulin
Turner Falls, Oklahoma
Pe'ePe'e Falls, Hawai'i (Big Island)
Cataratas do Iguaçu, Brazil/Argentina
Bonus Waterfalls Mentioned:
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John Leeman
Shannon Dulin
This week we talk about snow forecasting as the winter season starts to wrap up and try to figure out if you're really happier in the morning or not!
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John Leeman
Shannon Dulin
Ever wondered how geologists figure out when a landslide happened? Or how ancient river terraces and glacial deposits get dated? This week, we dive into the detective work behind dating geomorphic features! 🌍🔬 From tree rings to cosmic rays, we explore the fascinating methods geologists use to reconstruct Earth’s history and assess natural hazards.
Why Dating Landslides and Other Features is Hard
Dating Techniques in Geology
Ever wondered if your favorite neon-orange snack has hidden superpowers? This study explores how strongly absorbing molecules, like those found in food dyes, can reduce light scattering in biological tissues—making them temporarily more transparent! Researchers applied tartrazine (a common food coloring) to live mice and were able to see internal structures like blood vessels without invasive procedures. The discovery could improve biomedical imaging, but we’re mostly just fascinated that Dorito dust might have unexpected side effects!
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John Leeman
Shannon Dulin
We just wrapped up our first-ever on-site GEARS Workshop at UTEP and it was a massive success! 🎉 Tune in as we break down the highlights, what we learned, and how this hands-on geoscience training is evolving for the future.
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John Leeman
Shannon Dulin
This week, it's time for our 2025 resolutions show, where we see how we can improve this year and discuss everything that's changed in the past year!
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John Leeman
Shannon Dulin
This week we wrap up our finding faults show started oh so long ago! Learn how to identify faults in the field and then relax with a coffee with a physicist! A perfectly spherical coffee on a frictionless plane that is!
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John Leeman
Shannon Dulin
This week, we’re thrilled to welcome Joshua Pearce to the show! We dive into the world of open-source hardware for academic labs, the challenges and rewards of open-sourcing projects, and the exciting opportunities it creates for researchers and the general public alike. Tune in for a fascinating discussion about innovation, making, and the future of accessible technology!
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John Leeman
Shannon Dulin
Shannon went to AGU and we're updated on the meeting and what cool new science things she saw!
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John Leeman
Shannon Dulin
Faults are fractures in the Earth's crust where movement has occurred, creating features that are critical to understanding geological processes. In this episode, we explore how to recognize fault zones in the field, examine their widths at different depths, and analyze the breakage patterns and deformation features that define them.
Importance of identifying faults for earthquake research and infrastructure planning: Seismic Hazard and Risk - IRIS
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John Leeman
Shannon Dulin
Lithium, often called "white gold," is a critical resource powering modern technologies like electric vehicles (EVs), renewable energy storage, and more. This week, we explore lithium's geological formation, mining, processing, and its growing importance in the energy revolution. We also dive into exciting developments in Arkansas, which could make the U.S. a major player in domestic lithium production.
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John Leeman
Shannon Dulin
Gold has been a symbol of wealth, beauty, and power for millennia, but its importance extends far beyond jewelry and currency. From its formation deep in the Earth’s crust to its critical uses in electronics, medicine, and aerospace, this episode explores the fascinating journey of gold and why it continues to captivate us today.
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John Leeman
Shannon Dulin
Ever wondered how silver journeys from ancient rock formations to the tech in your pocket? In this episode of Don't Panic Geocast, we dig deep into the fascinating world of silver—the metal that's shaped economies, inspired legends, and powers modern technology. From its formation in Earth’s crust to the precise science of extraction and refining, we’ll explore how silver’s unique properties make it indispensable in everything from solar panels to medical tools. Tune in to learn why this shiny element is more valuable—and more complicated—than you might think!
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John Leeman
Shannon Dulin
This week, we dive into the fascinating world of coal—its origins, types, and the role it has played in shaping economies, past and present. We discuss coal’s formation in ancient swampy environments, the journey from mining to electricity generation, and the transition we’re witnessing as the world moves toward renewable energy sources. We wrap up with a Fun Paper Friday that challenges the classic "Infinite Monkeys Theorem"—could monkeys really type out Shakespeare if given enough time?
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John Leeman
Shannon Dulin
Throughout human history, certain minerals have held immense power, shaping economies, societies, and entire civilizations. In this economic rocks series, John and Shannon discuss how essential minerals like salt, gold, and coal influenced historical events and continue to impact modern geopolitics. This week we start with salt and how it is essential to many aspects of our day to day.
This week's Fun Paper Friday features a study on the leaf-mimicking abilities of Boquila trifoliolata. The vine is capable of changing the shape and size of its leaves to resemble those of neighboring plants, potentially as a form of camouflage against herbivores. But the most surprising part? It can even mimic artificial plastic leaves. This finding challenges existing theories that leaf mimicry is driven solely by chemical signaling or genetic exchange between plants, suggesting instead that Boquila may possess a form of plant vision through specialized light-sensitive cells called “plant ocelli.” This discovery opens new possibilities for understanding plant sensory and adaptive behaviors.
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John Leeman
Shannon Dulin
In our 400th episode, we take a moment to reflect on some of our favorite past episodes and Fun Paper Fridays that have brought joy, knowledge, and a good laugh to the show. From memorable guests to quirky science papers, this episode is a tribute to everything that makes the Don't Panic Geocast special. Join us for this nostalgia-packed episode where we look back at the highlights of 399 episodes!
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John Leeman
Shannon Dulin
