The Mesa Falls Tuff is a tuff formation created by the Mesa Falls eruption that formed the Henry's Fork Caldera that is located in Idaho west of Yellowstone Park.[1] It is the second most recent caldera forming eruption from the Yellowstone hotspot and ejected of 280 km³ of material. This eruption, 1.3 million years BP, was preceded by the Huckleberry Ridge Tuff and succeeded by the Lava Creek Tuff both of which were created by the Yellowstone hotspot.[2]