Katla volcano volcano
Volcano type	Subglacial shield volcano
Location	South Iceland, 63.63°N / 19.05°W
Summit elevation	1512 m (4,961 ft)
Last eruptions	920 AD, 950 AD (?), 1150, 1177, 1245, 1262, 1311, 1357, 1416, 1440, 1450, 1500, 1580, 1612, 1625, 1660-61, 1721, 1755-56, 1823, 1860, 1918, 1955(?), 1999(?), 1918
Typical eruption style	explosive basaltic and dacitic eruptions, voluminous lava flows.

Background

Katla volcano, located near the southern end of Iceland's eastern volcanic zone, is hidden beneath the Myrdalsjökull icecap.

The subglacial dominantly basaltic volcano is one of Iceland's most active and is a frequent producer of damaging jökulhlaups, or glacier-outburst floods. A large 9 x 14 km subglacial caldera with a long axis in a NW-SE direction is up to 750 m deep. Its high point reaches 1380 m, and three major outlet glaciers have breached its rim.

Although most historical eruptions have taken place from fissures inside the caldera, the Eldgjá fissure system, which extends about 60 km to the NE from the current ice margin towards Grímsvötn volcano, has been the source of major Holocene eruptions. An eruption from the Eldgjá fissure system about 934 AD produced a voluminous lava flow of about 18 cu km, one of the world's largest known Holocene lava flows. Katla has been the source of frequent subglacial basaltic explosive eruptions that have been among the largest tephra-producers in Iceland during historical time and has produced dacitic explosive eruptions during the Holocene.

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Source: GVP, Smithsonian Institute