In this episode, we dive back into the bedrock of America to reveal which state holds the crown for the oldest rocks in the U.S.! Join us as we unravel the mysteries of ancient metamorphic formations. From the Morton Gneisses in Minnesota, to the Wyoming craton out West, and ending in Upper Michigan, you'll find out what the oldest rocks are, and how we know! Hit that subscribe button, because this episode rocks!

The paper that served as the basis for this episode is Frost, C.D., Mueller, P.A., Bickford, M.E., and Stern, R.J., 2025, USA’s oldest rock? A simple question with a complex answer: GSA Today, v. 35, p. 4–10,
https://doi.org/10.1130/GSATG613A.1.

00:00 Introduction and Episode Overview

00:50 Setting the Stage: America's Oldest Rocks

02:28 Understanding Metamorphic Rocks

05:18 The Importance of Rock Ages

09:55 Zircon and Uranium-Lead Dating

14:16 Metamorphism and Zircon Growth

22:05 Metamorphic and Igneous Rock Processes

23:32 Understanding Zircon Inheritance

24:32 Determining Rock Ages

27:21 Challenges in Identifying Rock Types

31:44 Oldest Rocks in the United States

36:52 Technological Advancements in Geochronology

42:51 Conclusion and Further Research

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Join us as we explore the towering history of ancient mountain ranges, delve into the mysteries of the Appalachian Mountains, and break down the geological story behind the Gettysburg region. From the immense rift basins on the East Coast to the intricate details of the Allegheny Orogeny, this episode promises a thrilling ride through Earth's dynamic layers. Get ready to rock with some punny sediment tales and discover how past geological events shaped the terrain we see today! The Birdsboro basin may represent the larger Mesozoic rift basin that we only get small glimpses of today!

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What is the oldest rock you can stand on in the United States? As the title of Frost et al., 2025 says, it is a simple question with a complex answer. In this episode, we journey to the north-central United States, where you'll find some of the oldest rocks in North America. Join us as we go through the candidate locations and dive real deep into the weeds of zircon uranium-lead geochronology! The more you learn, the less you know.

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Rockstars! Welcome to our first-ever Planet Geo field trip! Join us as we hit the road to Gettysburg and dig deep into the geology that shaped one of the most pivotal battles of the American Civil War. From the rocks that dictated troop movements to the geomorphology of battlefield ridges, we're taking you on an epic journey. Discover how ancient sediments and volcanic flows set the stage for a historic showdown. Plus, we explore the stunning South Mountain - it's a rock-solid adventure you won't forget. Ready to field trip? Subscribe and join us on this geo-exploration!

The full series on the Geology of Gettysburg (7 parts, loads of custom images and amazing content!) is now available on our custom learning-geology-on-the-go app - CampGeo. Download using the link below!

Download the CampGeo app now at this link.

On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
You can also learn the basics of geology at the college level in our FREE CampGeo content series - get learning now!

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Welcome to another thrilling episode of PlanetGeo! In this episode, we dive deep into the jaw-dropping geology of the White Cliffs of Dover. We explore the formation and significance of chalk, a rock star in the geologic world. Learn about its formation during the late Cretaceous period, its economic uses, and its pivotal role as an aquifer system in Europe. From the fascinating microscopic coccolithophores to the sweeping landscape of the English coastline, this episode is sure to keep you on the edge of your rock hammer! Don't take it for granite! Tune in and discover the geological story behind one of the world's most iconic landmarks.

Download the CampGeo app now at this link.

On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
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Join us as we explore the (lack of) intersection of geoscience and entrepreneurship. In this engaging discussion, we delve into the importance of business acumen in geological sciences, but also highlight the cultural obstacles within the field. We share personal insights and experiences while discussing how educators and institutions can better prepare students for innovative roles in geoscience. Tune in for a thought-provoking conversation packed with rock-solid ideas and practical solutions! 🌍🪨💡

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On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
You can also learn the basics of geology at the college level in our FREE CampGeo content series - get learning now!

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In this exciting episode, we dive deep into the natural and geological wonders of the Mississippi River with Boyce Upholt, author of 'The Great River.' Join us as we unravel the mysteries and magnificence of this iconic waterway, exploring its historical, ecological, and engineering marvels. Boyce shares his personal journey, the challenges of writing this extensive book, and fascinating insights into the Mississippi’s floodplains, levees, and more. If you're ready to rock and roll down the river, hit play and let's get started!

Download the CampGeo app now at this link.

On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
You can also learn the basics of geology at the college level in our FREE CampGeo content series - get learning now!

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Join us as we dig deep into the world of cobalt! This episode covers everything from the explosive growth in cobalt demand to the intriguing geology behind this critical element. We traverse through magmatic, sedimentary, and laterite cobalt deposits, touching on the societal and environmental issues tied to cobalt mining. Fun and intriguing, this episode is sure to rock your world with cobalt facts unseen! Don't miss the deep dive into where you can find this blue-hued marvel and why it's essential for today's energy transition.

Download the CampGeo app now at this link.

On the app you can get tons of free content, exclusive images, and access to our Geology of National Parks series.
You can also learn the basics of geology at the college level in our FREE CampGeo content series - get learning now!

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