Geomagnetic micropulsations

Abstract

A DETAILED analysis of geomagnetic micropulsations has been carried out on records obtained at Albert Head between November 29, 1956, and February 16, 1957. Albert Head (approximately 48° 23′ N., 123° 29′ W.) is situated by the sea near Victoria, Vancouver Island, British Columbia. The records were obtained from three mutually perpendicular air-core induction coils, each 20 ft. in diameter, mounted in a rigid wooden octahedron 1. The records were analysed by visual inspection: more than 300 fluctuations were identified with periods ranging from 15 to 400 sec. Their amplitudes were read and reduced by simple computation to components X (north), Y (east) and Z (vertically downwards). Plots were made of these three components against the period T of the oscillations, but yielded little information. There was a tremendous scatter in the points, and it was impossible to draw any mean curve through the data. The only conclusion that could be drawn was that, in general, the amplitude appeared to increase with the period. © 1959 Nature Publishing Group.