and explosive eruptions. 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 effusive
basaltic eruptions. In the last 3000 years a
mixture of
both lava and tephra has
been dominating.The
chemical composition of erupted material from Hekla
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