Temperature and water content cycles within magma reservoirs linked to eruptive style
A new study published in Geology uses pockets of melts trapped within crystals to understand the conditions occurring beneath volcanoes before explosive eruptions. Volcanologists from Johannes Gutenberg University Mainz (JGU), Leibniz Universität Hannover in Germany and Uppsala University in Sweden have discovered that the temperature and water content of magmas varies through the lifecycle of a volcano, and that these variations occur in cycles in relation to the fresh input of new magma from below. The study suggests that the point at which an eruption occurs within these cycles may control whether the resulting eruption is explosive, which produces lots of ash and affects a wide geographical region, or simply erupts effusively creating lava flows or domes, lessening the hazards to nearby populations.