The 1973 Heimaey eruption started on 23 January with the opening of a 1600 m long fissure on the east side of the island, about 400 m east of the outskirts of the town. During the first hours lava issued from the entire fissure in 50-150 m high glowing fountains. A day later the eruption continued from two craters, and on 6 February only one crater remained, where activity continued until 26 June, when the eruption came to an end. By that time 417 houses had been destroyed by lava and tephra and the remainder of the town was covered with millions of tons of tephra. The total volume of the eruption products was 250 million cubic metres (230 million m3 as lava and 20 million m3 as tephra). The chemical composition of the products is alkali basalt, murgearite to hawaiite.
Link in Icelandic: http://www.eyjar.is/eyjar/frameis.html