Hierro volcano (Spain) - Smithsonian / USGS Weekly Volcanic Activity Report for 27 March-2 April 2013 (New Activity / Unrest)
On 18 March seismic activity at El Hierro sharply increased. Earthquakes were initially located around the NW tip of the island, at about 20 km depth, then later migrated W about 12-15 km offshore W of El Hierro Island, at similar depth. About 100 earthquakes of Mb 3.5 (body wave measurement) or greater had been located, many of them felt by residents.
Mi, 27. Mär 2013, 06:0006:00 AM | VON: VN
The biggest events occurred on 29 March (Mb 4.7) and 31 March (Mw 4.6, moment magnitude) both at 20 km depth. IGN's GPS data showed inflation of the island, with maximum deformation at the westernmost station of about 10 cm in the horizontal component and about 11 cm in the vertical. Deformation rates reached a maximum during 23-24 March.
An increase in carbon dioxide flux was observed in the W area.
Rockfalls were reported on the steep slopes, especially during 26-29 March. On the evening of 27 March the Plan de Protección Civil por Riesgo Volcánico (PEVOLCA) raised the Volcanic Alert Code for the population to Yellow, and closed the access to the W part of the island.
Source: Instituto Geográfico Nacional (IGN)
From: Global Volcanism Program, 2013. Report on Hierro. In: Mayberry, G (ed.), Weekly Volcanic Activity Report 27 March-2 April 2013. Smithsonian Institution and US Geological Survey.
Mo, 25. Mär 2013, 07:24
The likelihood of a new submarine eruption in the near future is increasing. Earthquakes and pulsating strong tremor continued with little changes, and a trend towards stronger quakes (a magnitude 4 event this morning), and shallower quakes as well (many at around 11-12 km depth today). ... Read all
Sa, 23. Mär 2013, 07:23
The scenario of an eruption in the near future is becoming increasingly likely. ... Read all