Geography Of The Katla Volcano
The Katla volcano is one of the largest volcanoes in Iceland. Katla is located on the southern end of Iceland's eastern volcanic zone, hidden by the Myrdalsjökull icecap. The Katla volcano reaches a total peak height of 1,512 metres (4,961 feet), and covers a total area of 595 km² (230 sq miles).
The Katla volcano caldera has a diameter of 10 km (6 miles) and is covered with 200 - 700 metres (660 - 2,300 feet) of ice within the caldera and outer volcano.

Katla Volcano Eruptions
The Katla volcano is considered one of the most dangerous volcanoes in Iceland. Most of the eruptions that have occurred have also resulted in major flooding from the glacial melting causing a glacier run.
A glacier run occurs when a volcano erupts underneath a glacier, which is the case with Katla. The ice that is covering the volcano melts due to the extreme heat, creating a large lake of water under the remaining ice. Either the wtare which breach the side of the volcano, or collapse the glacier, destroying the land beneath the volcano with massive flooding. It is essentially two disasters in one.
A total of sixteen eruptions have been recorded from the Katla volcano since 930. The last eruption occurred in 1918. There has not been a major eruption in 93 years but there was two small eruptions in 1955 and 1999 that did not break through the ice cover.
Volcano eruptions are rated on a scale of 0 - 8 known as the Volcanic Explosivity Index (VEI) based on ash cloud height, the total volume of lava and other products. All of Katla's eruptions have been between 4 - 6 VE.
The Katla volcano has an average eruption range of 40 - 80 years.

Recorded Major Eruptions
1918 - VEI4 or VEI5 1860 - VEI4
1823 - VEI3 1755 - VEI5
1721 - VEI5 1660 - VEI4
1625 - VEI5 1612 - VEI4
1580 - VEI4 934 - VEI5 or VEI6
Present Day Katla Volcano
The Katla volcano has been showing signs of severe unrest since 1999, and when the Eyjafjallajökull glacier erupted in March 2010, scientists began to monitor Katla even more closely. Over the past 1,000 years all three known eruptions of Eyjafjallajökull have triggered Katla eruptions within months after.
Increased activity with small earthquakes has occurred since 2010, but as of October 23rd 2011, the Katla volcano has yet to erupt again.

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