Volcanic Explosivity in Asia-Pacific
This map shows the density of volcanic eruptions based on the explosivity index for each eruption and the time period of the eruption. Eruption information is spread to 100km beyond point source to indicate areas that could be affected by volcanic emissions or ground shaking.
The original source of the data is a point dataset of worldwide historical volcanic eruptions occurring within approximately the last 11,500 years (to 2002). Adapted from Simkin and Siebert, 1994 "Volcanoes of the World: an Illustrated Catalog of Holocene Volcanoes and their Eruptions" and produced digitally by the Smithsonian Institution's Global Volcanism Program.
The volcanic eruptions were rated using the Volcanic Explosivity Index (VEI). The VEI is a simple 0-to-8 index of increasing explosivity, with each successive integer representing about an order of magnitude increase.