Multiple Explosive Events Observed in Yellowstone Volcano Super-Eruptions
New geological evidence suggests that the last super-eruption at Yellowstone volcano, which occurred 631,000 years ago, was not one huge explosion but a series of eruptions or multiple vents spewing volcanic material in rapid succession. Scientists have found four previously unrecognized ignimbrite units at Sour Creek, suggesting at least four eruptive pulses. They also found two structures that appear to be eruptive vents, which may have been the sources of these rocks. Researchers at the volcano now plan to carry out detailed examinations of the newly discovered units and the boundaries between them.