Earthquakes in Iceland

Abstract

IN NATURE, vol. xxi. p. 89, I see the earthquake which occurred in Iceland on September 24 last ascribed to “volcanic eruptions in the Krísuvík Mountains, a locality where eruptions have not been known within the memory of the present generation”. The use of the word “eruption” here is misleading, for though the earthquakes, which frequently occur at Krísuvík, are no doubt caused by volcanic action, nothing of the nature of an eruption, in the usual sense of the word, has been known to occur there within the historical period. The boiling springs, mud caldrons, and sulphur deposits, for which Krísuvík is noted, are, on the authority of Prof. Bunsen (Letters to Berzelius), to be ascribed to a pseudo-volcanic action occurring at comparatively slight depths. Though slight earthquake shocks have frequently occurred, during the last eighteen months, while I was at Krísuvík, I have never observed that they had any effect on the boiling springs and other thermal phenomena.