Report on Erta Ale (Ethiopia) — 22 January-28 January 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 22 January-28 January 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Erta Ale (Ethiopia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 22 January-28 January 2003. Smithsonian Institution and US Geological Survey.
13.6°N, 40.67°E; summit elev. 613 m
All times are local (unless otherwise noted)
A team of French scientists who visited the summit of Erta Ale on 4, and 13-14 January noted significant changes in morphology and activity at the volcano in comparison to several months previous. As has been the case for decades, a lava lake was present in the W part of the S pit crater. It was 120 x 80 m in size and its surface was ~100 m below the crater rim. Observers saw lava fountains spraying above the lake, as well as convection within it. The lava lake and resulting platform were higher than when observed in April 2002. Abundant SO2-rich gases were released that were not noted during earlier visits.
Geologic Background. Erta Ale is an isolated basaltic shield that is the most active volcano in Ethiopia. The broad, 50-km-wide edifice rises more than 600 m from below sea level in the barren Danakil depression. Erta Ale is the namesake and most prominent feature of the Erta Ale Range. The volcano contains a 0.7 x 1.6 km, elliptical summit crater housing steep-sided pit craters. Another larger 1.8 x 3.1 km wide depression elongated parallel to the trend of the Erta Ale range is located SE of the summit and is bounded by curvilinear fault scarps on the SE side. Fresh-looking basaltic lava flows from these fissures have poured into the caldera and locally overflowed its rim. The summit caldera is renowned for one, or sometimes two long-term lava lakes that have been active since at least 1967, or possibly since 1906. Recent fissure eruptions have occurred on the N flank.
Source: Jacques-Marie Bardintzeff from Université Paris-Sud and Franck Pothé from Terra Incognita