The Volcanic Zones of Iceland Explained

The volcanic zones of Iceland are the key to geology. A list is found in the newly published book, Náttúruvá á Íslandi:

Here the 7 volcanic zones are shown, names in Icelandic.

When this is compared with the convection rolls model, a theoretic pattern does emerge:

The volcanic zones of Iceland

A: The Snæfellsnes Volcanic Belt is basicly found end to end of two polygons, passing through the third, similarly as B and H.

B: The Reykjanes Volcanic Belt is based on one polygon, but the second part extending out to the ocean forms a continuity, so it resembles A and H.

C: The West Volcanic Zone covers two polygons in a similar way as F, but on most maps it does not fully cover the polygons from east to west. It then turns north around 65°N, coming to an end rather abruptly.

D: The Mid Iceland Volcanic Zone of Hofsjökull does provide a continuity of volcanic activity from the WVZ (C) to the EVZ (F). According to the system, it should be related to C, as the rifting process should be originated from there. The system is connected to a system added with dotted outlines, marke I, of Skagafjörður.

E: The South Iceland Volcanic Belt is found as a continuation of F, but is not a rift zone, as it does all belong to the Eurasian Tectonic Plate and is presumed to drift with it as a whole. The same type of tension is found theoretically to occur within the two polygons firstly for the one of Eyjafjallajökull and Katla, and secondly for the Vestmannaeyjar Islands polygon.

F: The East Volcanic Zone is the probably most clearly defined of any of the volcanic zones. The west side and east side are accurately marked by the sides of three polygons, extending to the southern part of the fourth polygon of Askja.

G: The North Volcanic Zone is oriented north to south, with volcanic systems arranged in a right hand en echelon pattern. The main polygons form the central axis, but at the sides, a large number of polygons are involved, as in the north, the network of division lines becomes more complex than in the southern half of Iceland.

H: The Öræfajökull Volcanic Belt has been quite obscure due to the fact it is mainly found under the glacier Vatnajökull. It convers two polygons, very much like A and B, extending between Öræfajökull and Snæfell.

I: This is actually an extinct volcanic zone, but as it was active rather recently (less than 800,000 years ago) I want to include it. This is the Skagafjordur Volcanic Belt, responsible for rifting within the fjord for a million years or so, according to Árni Hjartarson who wrote his PhD essay on the topic. The central axis is found exactly 3° west of the central axis of the NVZ (G), which is logical according to the convection rolls system, where similar conditions are repeated every 3° from east to west along each parallel.

The South Icelandic Seismic Zone and a part of the Tjörnes Fracture Zone are marked on the map for reference. The Grímsey Oblique Belt also connects with the Kolbeinsey Ridge north of Iceland, not shown on the maps.

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