Novarupta ash fall compared to that from recent eruptions.

Alaska Peninsula map showing some of the of volcanoes, with Novarupta ash fall compared to that from recent eruptions. The volume of volcanic ash from Novarupta was more than from all other historical Alaska eruptions combined. Ash from seven prehistoric eruptions, all younger than 6,000 years and approaching the volume of the 1912 event, are found within 500 miles (800 km) of Anchorage, including ash from Hayes volcano (Bacon, et al., 2012)