Question: how was mt eyjafjallajokull formed?
Answer: Eyjafjallajokull is a strato volcano. ... A large magma chamber under the mountain feeds Eyjafjallajokull. The chamber derives magma from the tectonic divergence of the Mid-Atlantic ridge. The volcano is a part of the chain of volcanoes that stretch across Iceland, including volcanoes like Hekla, Katla and Grimsvotn.