Furnas EU laboratory volcano on the island of
São Miguel in the Azores has been active over the past 90,000 years. Explosive
activity has dominated its history with at least 10 explosive eruptions
occurring during the last 5.000 years. Most of these eruptions have involved
phreatomagmatic activity and were not equally spaced in time, indicating that
the behaviour of the volcano was episodic. Volcanic hazard maps have been
prepared for the two end member (largest & smallest) eruptions of the last
5,000 years. The hazard maps use a variable vent location to predict the
maximum ash fall thickness based on the two eruptions.
Plans for evacuation, in the event of a future
eruption have been drawn up on the basis of these maps and have identified
features of the environment and society of the Furnas district which could
affect the success of evacuation. Data from emergency planning perspectives are
being integrated into a Geographical Information System (GIS). This will allow
interactive variation of eruption parameters (e.g. column height, wind
direction and strength) to test evacuation models and enable the hazard
assessment to be updated as data become available during the progress of an
actual eruption.