Náttúrufræðingurinn

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Náttúrufræðingurinn - 1965, Blaðsíða 28

Náttúrufræðingurinn - 1965, Blaðsíða 28
74 NÁTTÚRUFRÆÐINGURINN and containing a geographical description o[ Iceland. This eruption in all probability was on the Reykjanes ridge and so was with certainty the oldest submarine eruption nientioned in Icelandic sources. That eruption occurred iu 1211, coinciding with great earthquakes. In old annals Sörli Kolsson is said to have discovered the new Eldeyjar (Islands of fire) tliat year, whereas the old ones disappeared from tlie spot where they had always been. This indicates tliat there was volcanic activity in this area long before 1211. Eruptions occurred southwest of Reykjanes in 1226/27, 1231, 1238, 1422, 1783, 1830 and 1879, probably also in 1240 and 1583 and possibly about 1340 and in 1884. Three ol these ernptions are known to have built up islands, viz. the 1211 eruption (more than one island), the 1422 eruption antl the eruption in 1783. The only one of these islands describecl by eyewitnesses is the island observecl for the lirst time May 3rd, 1783 by captain Mindelberg and liis crew of the Danish brig Boesand. The captain drew a sketcli of the island (Fig. 4). The island reached a diameter of al least 0,9 km. Tlie Danish Government showed a great interest in this island wliicli rcceived the name Nýey (Nyöe) : Ncw Island. A royal decree was aroused as to the eflect that an expedition sliöuld be sent to the island to hoist the Danish flag and set up a 3 ells high stone inscribed witli the royal insignia. The stone never found its way to the island sirnply because the island could not be found in the autumn of 1783. In early June 1926 fisherman on the fishing vessel Bragi from Njardvik observed signs of submarine ernption short northeast of Eldey. 'l'he sea was first bubbling and later spouting and dead fishes floated up. These arc the last signs of volcanic activity observed on the Reykjanes ridge. Submarine eruptions have also occurred off the north eoast. To quote a contemporary annal of 1332: ”... frorn the F'ljót and from many other districts in the North of Iceland a new island was seen to have emerged to the northwest of Grímsey". On a Dutcli map of 1507, made by Johannes Ruysch, an island is indicated between Iceland and Greenland togethcr with the following rernark: ”This island was ablaze in 1456“. Jan Mayen may possibly be the island referred to. In 1755 there seems to have been an eruption somewhere north of Iceland, but the position is unknown and again it may possibly liave been Jan Mayen. At thc end of 1867 and in January 1868 thcre was definitely a submarine erup- tion off Tjörnes, a short distance to the north of Mánáreyjar. ()n Bishop Thórdur Thorláksson’s map of the North Atlandc of 1669 there ís an island located (juite a long way to the southwest of Iceland and this island is said to have been seen by Spanish sailors in 1613. We liave no otlier knowledge of tliis island. It may liave been on the Reykjanes ridge. Tliere is some evidence of volcanic activity sliort to the south of the Vest- mann Islands in September 1896, sliort after the great earthquakes in South Iceland, wliieh also affected the Vestmannaeyjar area. These evidences, liow- ever, are not conclusive of a submarine ernption having really occurred. But Nov. 14, 1963 it was found out for certain that the submarine fires olf the Vestmann Islands area were not exlinet.
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