Erta Ale

 

 I have to admit... to me the most fascinating part of either Geology or Geography has to be volcanoes.

I  think that one of the volcanoes and its surrounding areas that has most caught my eye and kept my interest for the longest is Erta Ale at the Danakil depression in Ethiopia.  

Erta Ale is a continuously active shield volcano in the Afar region.

It is 613 metres high with a base with a diameter of nearly 30km. The summit caldera contains two large steep-sided pit craters, the N and S (or "central") pit craters, and one smaller pit at the south-east side of the N pit. The caldera appears to have been formed by 3 overlapping circular collapse structures and has approximate dimensions of 1600 x 700m.  It always has one-sometimes 2 active lava lakes at the summit that occasionally over flow on the south side of the volcano.

It is the longest existing lava lake- it has been there since the early years of the 20^th century and is one of only 4 in the world- one other is Niriagongo- in the Congo.

It is known as the smoking mountain in local language and the southern lake is known as the gateway to hell.

Its last major eruption was on September 25^th 2005 that killed 250 livestock and forced thousands of people to have to flee- there was yet another lava flow in august 2007 that forced the evacuation of hundreds and leaving 2 people missing. A further eruption was reported on November 4^th 2008 by the scientists at Addis Ababa University.

In November 2010 following a period in which the lava lakes had been rising there were several short lava flows that emitted from the north lake, and a cone was built up around the lake due to the constant overflows.

By the end of January 2011 another small lake was observed around 10m below the crater floor.

This volcanic formation is the result of the splitting of the African rift valley that will eventually form two new plates- the Somalian and the Nubian plates.

As can be seen on this map- the two plates are spreading apart gradually giving us what is the red sea fault as well as the fault that runs down the east of Africa- now eventually probably in around a million years these two plates will finish splitting apart and form two new plates.