FRONTAL MICROSEISMS GENERATED IN THE WESTERN NORTH ATLANTIC OCEAN

Abstract

Case histories of six microseism storms generated by marine cold fronts are given. Seismograms from the New York City and Palisades stations of Columbia University and from Weston College Observatory were utilized together with 6-hourly synoptic North Atlantic surface charts. Definite correlations are made between stages of microseism activity and frontal positions over water. Microseism period is shown to vary with both distance of and water depth beneath cold fronts, with the latter apparently of greater significance. The observations tend to negate or minimize the importance of surf or any form of swell in producing the microseisms considered, and suggest atmospheric pulsations or turbulence to be a significant cause.