Ascent rates of rhyolitic magma at the onset of three caldera-forming eruptions

Important clues to the initiation and early behavior of large (super-) eruptions lie in the records of degassing during magma ascent. Here we investigate the timescales of magma ascent for three rhyolitic supereruptions that show field evidence for contrasting behavior at eruption onset: (1) 650 km3, 0.767 Ma Bishop Tuff, Long Valley; (2) 530 km3, 25.4 ka Oruanui eruption, Taupo; and (3) 2500 km3, 2.08 Ma Huckleberry Ridge Tuff, Yellowstone....