active system in Iceland. The
activity has
changed in terms of frequency and type of eruptions with
time. The period
9000-7000 years
ago was dominated by effusive
basaltic volcanism, the period 7000-3000 years
ago was
characterized by infrequent but large explosive silicic eruptions at the
central volcano, and the last 3000 years have
been dominated by more frequent and smaller mixed silicic
/volcanoes/about-volcanoes/hekla/hekla-eruptions/