El Hierro volcano (Canary Islands) news & activity updates
El Hierro volcano (Canaries): increase in small earthquakes, almost no visible activity
The submarine eruption south of El Hierro Island could be in a process of change: While visible activity on the sea surface above the vent, as well as harmonic tremor signal (thought to be more or less proportional to erupting magma flux) have nearly ceased, the number of earthquakes under the island has increased sharply since yesterday.
Wed, 15 Feb 2012, 23:4423:44 PM | BY: T
On 15 February, more than 20 quakes were measured. Most of the earthquakes were very small, well below magnitude 2, and were clustered beneath the NW and SW sectors of the island at depths of around 10 km.
There is no conclusive interpretation of this measurement. A possible (and usually assumed) scenario is that rising new magma from the mantle reservoir is creating new intrusions and rupturing rock to create pathways in the crust under El Hierro, not using the same paths as until now. That would explain why less magma is currently being erupted at the current vent(s). In that scenario, the eruption will continue, perhaps even from a different vent, and an increase in magma output is going to be expected any time soon. However, this is speculation.
The earthquakes could as well be related to some other (known or unknown) process, e.g. gravity-induced adjustments that respond to pressure changes and occur within previously ruptured areas of the crust beneath the island.
The next days or weeks will show what happens next.
Links / Sources:
Links / Sources:
- Earthquake-report excellent coverage of the El Hierro eruption
- IGNSerie El Hierro (Instituto Nacional Geográfico) with online data of seismic activity, daily reports and more
Thu, 9 Feb 2012, 00:01
El Hierro volcano (Canary Islands) activity update: active jacuzzi with strong stain at ocean surface, occasional hot lava balloons floating up
Tue, 7 Feb 2012, 22:22
The submarine eruption at El Hierro continues at low levels with no significant changes. The stain of the ocean above the vent(s) remains strong, and occasionally, smoking lava balloons are seen rising. read all
Mon, 30 Jan 2012, 17:58
El Hierro volcano (Canary Islands) eruption update: steaming lava balloons at surface, new insights from recent bathymetric studies
Mon, 30 Jan 2012, 00:01
El Hierro volcano (Canary Islands, Spain) activity update: submarine effusive eruption, steaming lava balloons arriving at ocean surface above vent
Fri, 20 Jan 2012, 09:11
A long-awaited press release of the Spanish Government and the Oceanographic Institute was now published and presents the results of the latest bathymetric survey conducted last week by the crew on board Ramon Margalef , including the new bathymetric map of the new submarine volcano: the vent is now a depth of 130 m. ... read all