Continental Drift en miniature – The Lava Lake of Erta Ale
Real lava lakes are a rare sight on our planet. Over all there are only a handful currently active and of course somehow they have to be accessible to stand at its crater rim. In Ethiopia’s Danakil Depression one of the most beautiful, majestic and mystic of its kind can be seen, the lava lake of Erta Ale volcano.
Step by step more and more black lava rocks start to peep through the desert dust being swirled up by our jeeps. For the cars the journey is over as only camels can take us further, well, our baggage and equipment as we are up for a hike. Stoically chewing the animals trot through the moon landscape of solidified lava. The rough terrain doesn’t really impress the animals but we are definitely having fun walking at night over brittle, hence collapsing but also razor-sharp lava rocks. Swinging from one side to another the camels drag our gear and food onto the mountain. Fortunately freight can’t get seasick.
Having reached the 613 metres high summit of Erta Ale, the volcano presents us a terrific panorama as at our feet the rugged caldera starts with its 1.2 kilometres length and some 500 metres in width. In the far distance we can see two holes. Those are pit craters, and shield volcano has one in the north as well as another one in the south. From latter one an orange fiery glow rises up into the night sky.
There are only four active lava lakes in the world; sometimes five, when activity returns to the Ambrym volcanoes of Vanuatu. And what is a common thing between all volcanoes? Right. A Prussian would surely answer: Well, you only find them at the arse of the world; reflecting the sheer remoteness of such places. And Danakil Depression will not disappoint lovers of remote areas as it is located in the Afar triangle, that’s where Ethiopia borders with Eritrea and Nubian as well as Somali and Arabic tectonic plates are shaking hands to say goodbye as they are moving apart from each other. Right at the top of that rift is the Afar region, the Danakil Depression, and it is no surprise that all things called volcanism are everything but calm over here as it is home to a fourth of all volcanoes of Africa.
A lake of lava is something special though at it symbolises a direct connection between a magma chamber, the actual reservoir of a volcano, and the surface of Earth. In terms of Erta Ale the diameter of its huge caldera gives a conclusion how big such a magma chamber is. Each lava lake is a very fragile system and many aspects have to show their consistency and stability to establish a convective flow; a flow, where the amount of hot magma flowing upwards is in balance with the quantity of lava sinking down again. Also the process of lava cooling down at the volcano’s surface is important, as too solid lava would let the lake “freeze”. The balance between liquid hot and solidified cold material does not automatically mean that the lake’s level is the same all the time. In terms of Erta Ale the volcano spills over from time to time, creating huge lava flows.
Enthusiasts won’t find much sleep at such places and conditions. Time flies and while sunset has happened just now, the sunrise already looms at the other side of the hemisphere. In the first night the lava lake didn’t show much activity. Its level sank down and rose up again, but in general the skin on the liquid magma often got sealed by a thick skin, that was sometimes even thicker and harder than usual. It didn’t take much time and the boiling but locked-in volcanic activity breached through with a loud cracking noises. The same sort of noise one knows from cutting ceramic tiles, but this time emerging from deep inside the mountain. A quite blood-curdling moment, as it makes one realise that the spot at one’s feet is definitely not solid. The crack divided the solidified lava in two giant plates. When they sank down they revealed the entire boiling lava lake. Its full power and heat radiated right into my face and burnt eyebrows as well as eyelashes. Those singing hot circumstances don’t really impress mice climbing out of the crater. First time I saw them made me thinking volcanic gas makes me nuts, but fortunately the kestrel, preying upon them at daytime, rehabilitated me. It is very surreal to meet complex life forms at such hostile places.
Among the world’s lava lakes Erta Ale is definitely special as compared with the likes of Nyiragongo or Ambrym, that are quite boiling plus emitting a tremendous amount of gas, Erta Ale is pretty cushy. For visitors that often means clear and calm circumstances and an undiluted view of the 60 metres in diameter measuring lava lake that some 20 metres underneath one’s feet. At daylight the lake appears like any other volcanic landscapes, that is dull, black, rugged and razor-sharp. At night-time, in particular at dusk and dawn, it is the opposite as universe and the glow of the fire our Earth is made of join forces to deliver a spectacle of epic proportions. Then one can spot lava plates looking like continental tectonic plates slowly strolling all over the lake, bumping into each other, drifting apart to finally sink down again while at the edges lava boils hissingly as it unleashes gas it was carrying all the way from inside the Earth.
The second night was less calm as on time at blue hour the lava lake awakened and began to spill over. Step by step lava flooded the whole pit crater and heat was unbearable, in particular at the southern crater rim. Even after hours, after the small effusive eruption has ended, one could still see and feel pockets of red glowing lava in the crater. That’s when camera and shutter have to do overtime and one runs out of memory cards as the combination of full moon, deep-blue night sky, stars and an overflowing lava lake are even more rare and unique. That night the lava lake terrace (the solidified lava surrounding the actual vent) got lifted by some 0.5-1 metres. Its activity sounds relaxing, like the ever washing waves of the Ocean and that’s also the way lava boils: liquid like unleashed water and everything but tough and chewy. Though it needs only the blink of an eye to turn the mass of melted rocks into a pulp becoming more and more sticky.
Despite Erta Ale active for most of the time, also compared to other lava lakes, it isn’t immune from completely solidifying as well or from activity moving from one pit crater to another. At the beginning of the century Erta Ale froze for about 2 years, but then awakened again. Same happened to the lava lakes of Ambrym volcanoes, that are boiling again since 2009.
Erta Ale is calm, but no child’s playground and definitely not a volcano to be underestimated. Its last big eruption was in 2005, people had to escape leaving their stuff behind and also in 2010 the volcano flooded the lower terrace of its pit crater and lots of lava was only 10 metres away from the crater rim. To lovers of electronic music I recommend watching the volcano listening to the sounds of Jon Hopkins or Moshic (in particular his Salamat album).
In January 2012 as well as December 2017 tourists got attacked and shot dead in Danakil Depression, right at the caldera rim of Erta Ale. Such incidents have to be taken into consideration as Ethiopia’s border with Eritrea is not far away. Both countries waged a bloody war. In the past years touristic structures and travel industry developed well in the northeast of Ethiopia resulting in every Tom, Dick and Harry offering tours to the volcano. Since tourists often allow only the cheapest tour operator things like food supply, accommodation, territorial experience and safety suffer as guides as well as drivers often have no clue about what they are doing. Also a stuck jeep in the desert can become a serious threat.