S1E9 J18 Giant Dinosaurs and Plate Tectonics deep time, dinosaurs, geology, Jurassic, m4, plate tectonics, sauropod Listen Junction 18 of the M4 traveling west. This is the third episode from the Jurassic Period. https://www.richardtreves.com/podcast-player/490/s1e9-j18-giant-dinosaurs-and-plate-tectonics.mp3