Erta Ale volcano (Ethiopia): field report 29 Dec 2016 - 1 Jan 2017
Thu, 12 Jan 2017, 12:0512:05 PM | BY: T
During their 24 December 2016 to 6 January 2017 Danakil expedition our small group spent 3 full days on the summit area of Erta Ale (from 29 Dec - 1 Jan 2017) to observe the changing activity from the two active craters (vents) inside the shield volcano´s large summit caldera.
Erta Ale's lava lake on 29 Dec 2016 (image: Jens Wolfram Erben)
This is a summary of their observations: They report that from 29 to 31 December 2016 the level of the lava lake in the southern crater fluctuated between 0,5 and 1 m below the rim, changing about every 6 hours.
Most of the time there were smaller lava fountains (ca. 2 - 3 meters high) along the southern crater´s lava lake but these slowly diminished when the level of the lava lake started to rise again from a lower position.
This process of rising lava was thereby accompanied by more intense cracking of the cooled upper crust and extrusion of fresh red-hot lava through these cracks which then flowed across the black crust, engulfing large portions of it so that the entire lava lake´s crust got recycled into the rising, actively boiling lava lake. The whole southern crater area with the lava lake seems to be swelling up in an elliptical structure, with the diameter of the southern vent being about 5 - 7 m larger than one year ago. Despite the increased activity and high level of the lake within its encompassing rim no overflows occurred during these three days - the last one having occurred a few days before on 27 December.
Meanwhile, activity within the northern active crater has formed 3 hornitos, of which one was actively ejecting small volumes of lava. At nighttime, this active vent showed an orange-red glow, at times accompanied by a strong roaring sound (much like a jet engine).
The current elevated activity at Erta Ale started around the end of October 2016 and includes a number of occasions on which lava was overflowing from the lake in the southern vent. Some of these overflows went on for a prolonged amount of time, with the red hot lava flowing like a waterfall from the rim of the perched lava lake onto the caldera floor where it formed fresh pahoehoe flows. The large volume of lava extruded in the past few months seems to be significantly larger than what has been previously observed and is documented in reports dating back to 1971. In comparison to the situation at the end of 2015, the caldera floor around the southern vent has been covered with up to 3 m of fresh pahoehoe lavas which diverged
radially from the vent and represent an area of about 150 m diameter.
The overall elevated activity as well as large surface areas of fresh, degassing lava flows resulted in a strong emission of volcanic gasses, especially in the northern part of the southern crater with lava lake. The high activity and very hot, degassing lava flows made it impossible to walk across the caldera floor to the southern crater the same way as was still possible in early 2016. Irritation from sulfurous gasses can be dealt with using an adequate gas mask and safety goggles (sealing off the air around your eyes from the surrounding gasses).
The largest hazard are the fresh lava flows which might seem like they cooled down but are still red-hot liquid below the paper thin black shiny crust. With a lot of precaution, the southern tip of the perched lava lake could be approached as close as 3 m from the southwest.
9 January 2017: news from locals at Erta Ale base camp and summit area describes the lava lake to still maintain a high level within its perched rim above the southern vent, having a few smaller active fountains (up to 1 m high)."
Thu, 29 Dec 2016, 19:40
Erta Ale volcano (Ethiopia): intense activity continues, possible lava flows outside the caldera (?)
Activity remains elevated at the volcano in the Danakil. The latest available information show simultaneous effusive activity from both the north and the south crater - the latter, which contained the famous lava lake has been overflowing and building a new lava shield that started to partially fill the summit caldera. ... Read all
Wed, 7 Dec 2016, 08:47
Two participants on our tour in mid-late November sent us impressions from the very active Erta Ale volcano (lava lake currently overflowing) and Dallol (increased activity at the hot springs). Read all