Earthquakes During May

Abstract

ELEVEN strong earthquakes and many minor ones occurred During May. All the major ones had their epicentres in well-known seismic zones, and fortunately most were either in the sea or in uninhabited places on land. No really deep-focus earthquakes were among them, though at least three had deeper foci than is normal, namely, those on May 3 in the Kurlle Islands, and on May 8 and 30 off the coast of northern Chile. These were also three of the four strongest shocks of the month, the fourth being the earthquake on May 9, with a normal depth of focus, and epicentre near the coast of north-west Sumatra. Three local shocks are also worthy of note. The first, on May 1, was felt at Horta in the Azores ; the second was in southern California and was felt at Santa Monica, Los Angeles, Blythe and Elsinore with scale 4 (Modified Mercalli scale) ; the third was in France in the Departments of Nièvre and Saòne et Loire, being felt in the former at Chàteau-Chinon and in the latter at Anost with scale 3—4 (Modified Mercalli scale). Readings of instrumental records have been received from the central stations of the United States Coast and Geodetic Survey and Strasbourg, and from individual observatories at Cleveland (Ohio), De Bilt (Netherlands), Durham, Edinburgh, Kew, Stuttgart and Toledo.