Central Plateau Member rhyolite flow structures from the Yellowstone Plateau Volcanic Field

Photos of Central Plateau Member rhyolite flow structures from the Yellowstone Plateau Volcanic Field. A) An ogive from a road cut along Firehole Lake Drive. Ogives are pressure ridges that form perpendicular to the direction of flow from the compressive stresses that deform the highly viscous lava as it moves. B) A roadside outcrop exhibits rhyolitic flow banding, including an obsidian-dominated band (the glassy black rock) near the bottom of the outcrop. Photos by Lauren Harrison, Colorado State University, taken in May 2024.