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Western Iceland Earthquakes in January 2022

The earthquakes make people wonder – what is going on there? The location is outside the West Volcanic Zone and is by some regarded as intra-plate seismic activity.

Icelandic Met Office information. https://www.vedur.is/um-vi/frettir/jardskjalftahrina-i-borgarfirdi

This is a geothermal area, just south of the most powerful low temperature geothermal are in Iceland. Some large earthquakes occurred there in 1974 https://timarit.is/page/1453203#page/n0/mode/2up. According to the model considered here, with convection rolls found underneath, these earthquakes can be explained differently.

Map from: https://jardvis.hi.is/sites/jardvis.hi.is/files/Pdf_skjol/Jokull58_pdf/jokull58-einarsson.pdf

The location of epicenter can be compared with the West Volcanic Zone (WVZ), which closely resembles the East Volcanic Zone (EVZ) in many ways. The eastern margins of the WVZ and the EVZ are oriented in the same way, but the western margins differ.

The WVZ and the EVZ, the SISZ and the recent epicenters of recent earthquakes.

As the southern half of the WVZ is here regarded as a square, the N-S axis is vulnerable to shearing. The red lines west of the epicenter extend from the Reykjanes Ridge, and are supposed to be the up-welling division line between two convection rolls at the depth of 120 km, and another pair of convection rolls farther down, also up-welling. This causes tension, because the local convection rolls (in between red and blue lines) oppose the main drift of the North American Tectonic Plate, causing rifting. This causes earthquakes in the area, even though it is outside the WVZ as detected from the surface.

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