The Salmas (Iran) earthquake of May 6th, 1930

Abstract

Field investigations and bibliographical research into
the little-known but important Salmas earthquake in Northwest Azarbaijan
(Iran) provided the following results. The morning before the earthquake,
a foreshock (Mb — 5.4) centered, as the main shock, in the Salmas
Plain, killed about 25 people and incited a great part of the population to
spend the following night out of doors. The main shock (Mb = 7.3) occurred
the following night, on 6 May 1930 at 22h34m27s GMT and destroyed about
60 villages and 40 churches, killing about 2514 people, both in the Salmas
Plain and in the surrounding mountains. Its macroseismic epicentre was
at approximately 3S.15N 44.70E. The main shock was associated with 2
surface faults, with a maximum horizontal displacement of 4 m and vertical
displacement of over 5 m; the combined action of these faults was a
relative lowering, and a displacement to the east, of the Salmas Plain. Two
days later, the strongest aftershock destroyed one village at the northern
edge of the Salmas Plain.