The 2005 Dabbahu (Afar, Ethiopia) Rifting Episode: A Review of Latest Results and Current Research Activity

The recent volcano-tectonic activity in Afar started on September 4th while the major eruption occurred on 26 September 2005. The chief of the Dabbahu district, Mr. Mohammed Kello said that it was common to feel earthquakes in that locality previously but the rumbling noise, vibration and explosion in this recent crisis in September 2005 was disturbing both for animals and humans. During the major explosion in September, a mushroom shaped (when there is no wind) black smoke covered the sky continuously for three days and nights (24th to 26th) mixed with intermittently thrown out Obsidian debris. There was rain in the area which was unusual at that time of the year. The center of the vent sparked like a lighter at night once in a while as observed at a distance, as reported by Mr. Mohammed. The Da'Ure eruption occurred at about 5 km NE of Dabbahu's stratovolcano summit. Results from InSAR, GPS, seismology, petrology, and structural geology suggest that a 60-km-long rift segment ruptured in September 2005, with a dyke, up to 8 m wide, injected along its entire length. For its spatial extent and amount of opening, this ranks as the largest dike injection ever observed on land, comparable in magnitude to the entire 10-year-long Krafla (Iceland, 1975-1984) rifting sequence. We will review the latest results from ongoing geophysical, geochemical, and geological research on the Dabbahu rift segment.