Friday, September 28, 2012

[Geology2] El Hierro: Further inflation, earthquake epicenters become more scattered

Further inflation, earthquake epicenters become more scattered
Update Thu 27 Sep 17:26

Time and depth of recent quakes

Map of the quakes (red: within 48 hours, yellow: past week)

Current deformation charts of El Hierro (IGN)
Perhaps some interesting developments are starting to be visible at El Hierro: 
The number of earthquakes remains elevated (13 yesterday, 4 so far today), not usual compared to previous days, but their location and depths become more scattered, and several quakes including some above M2 are at about 15 km depth, i.e. inbetween the "usual" layers at 10 km (western El Golfo) or 20 km (southern part of the island) depth. 
A further inflation of about 2 cm has been measured at Restinga in the past 2 days, and at El Pinar, about 3 cm inflation is visible. 
The Frontera GPS station shows deflation of approx. 1 cm (probably because the epicenter are no longer only concentrated in the El Golfo Bay).
All 3 mentioned stations show almost no horizontal movement since many days.
Update Wed 26 Sep 10:32
The number of earthquakes remains elevated, but stable with about 10 usually small events detected per day. There are 2 areas where they occur - in a N-S zone in the western El Golfo bay at about 10 km depth and scattered in the SW part of the island near El Pinar at about 20 km depth.

Location of quakes during the past week

No comments:

Post a Comment