For the moment the eruption in El Hierro volcano has ended. The current harmonic tremor that is being detected might well be from hydrothermal activity that is currently in the area that erupted. But even if the eruption has ended, the area that erupted is going to be warm for many weeks to come. This is going to create hot springs below the sea level, among other ocean phenomena connected to this type of hydrothermal activity.
Harmonic tremor levels remain close to background levels at El Hierro volcano. Taken today at 16:05 UTC. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).
As for future activity in El Hierro volcano. It is important to remember that eruption activity might start again on a new fissure. But that would be pre-seeded by earthquake activity. After the eruption activity stopped there has been some earthquake activity. But it is not at that level I would expect before a new eruption where about to start in El Hierro volcano. For the moment however things remain quiet in El Hierro volcano. A relieve to the local people in the area I would think.
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I want to remind people of the volcano and earthquake forum. It allows for more discussions on volcanoes, earthquakes and other stuff that might not belong to this blog.