Latest on El Hierro

El Hierro Volcano (Canary Islands) : Red alert – spectacular increase of harmonic tremor

Last update: November 20, 2011 at 1:29 am by By 

Late night data update 19/11 – 23:16 UTC
– 15 M+1.5 earthquakes today
– Strongest earthquake being a 3.3 at 18:27
– Depth of the earthquakes since midnight : 16 to 23 km
– Harmonic tremor remains 
strong since 17:16 UTC tonight
– GOOD air quality all day long


Important update 19/11 – 17:46 UTC
– We have just noticed that the harmonic tremor is almost saturated again, the biggest change since the fallback on November 17. The second graph shows the harmonic tremor from November 17 when it collapsed, until the new saturated graph today.

Increase of harmonic tremor between 17:00 and 18:00 UTC on November 19 – image courtesy IGN


harmonic tremor from late November 17 until November 19 – Click on the image to see it in full size


Data update 19/11 – 16:37 UTC
– 10 M+1.5 earthquakes since midnight (a lot less than we have expected)
– Strongest earthquake being a 2.8 at 08:20
– Depth of the earthquakes since midnight : 16 to 23 km
– GOOD air quality values this morning

Update 19/11 – 16:37 UTC
– Ian Carson reports from El Hierro : Civil guard went out to sea in RIB (rigid inflatable) this morning. Spoke to English speaker also aboard. He said ‘volcano quiet today, stain still visible but much lighter than in past ‘Jacuzzi’ times.

for more, updates, and reports, go to: