The Earth's tectonic plates are made up of the lithosphere - that outer hard rock layer of the Earth.  In this episode, we talk about the lithosphere, the underlying asthenosphere, and the moho boundary between the crust and the upper mantle portion of the lithosphere.  And all in under 9 minutes!This is essential listening for students learning about Plate Tectonics!Interested in joining us on a trip?   Check out our field adventures here.Don't miss a thing!   Join our email list.Support the show (https://www.buymeacoffee.com/Geoetc)