200px-Volcano_scheme_svg

This is a diagram of a stratovolcano.

Cross-section through a stratovolcano (vertical scale is exaggerated):

 

1. Large magma chamber

2. Bedrock

3. Conduit (pipe)

4. Base

5. Sill

6. Branch pipe

7. Layers of ash emitted by the volcano

8. Flank9. Layers of lava emitted by the volcano

10. Throat

11. Parasitic cone

12. Lava flow

13. Vent

14. Crater

15. Ash cloud

Where the two plates meet, sometimes one moves down, while the other moves upward. As the plate that is moving down is forced deeper, parts of it begin to melt and form magma that rises to the surface, often in explosive eruptions. The plate that rises, tends to create large, classic, cone-shaped volcanoes called stratovolcanoes, such as Mt. Hekla.

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Explain why the eruption happened?

It is most likely that the eruptio happened because the tetonic plates that meet in Iceland and sometimes split apart with terrific results. Sometimes the plated go in different directions, up and down, but sometimes they move in different direction rubbing against one another. When a plate moves down (subduction), being forced deep, part of it begin to melt and form magma that rises to the surface, often in explosive eruptions. Subduction zones tend to create large, classic, cone-shaped volcanoes called stratovolcanoes, such as Mt. Hekla.

 

Done