UBC Theses and Dissertations
An analysis of short period (10-30 seconds) geomagnetic micropulsations Hassett, John Henry
Geomagnetic micropulsations are described and possible origins discussed. Previous work in Canada is reviewed with particular attention to the normal daytime Pc oscillations with periods from 10 - 30 seconds. A description is given of the work done correlating the amplitude and direction of the exciting vector at two stations. Field work at Ralston, Alberta during July -August 1959 is described in detail. A digital computer is used to obtain the auto-correlation coefficient and the covariance of the horizontal components of the vector. From these two paramenters the dominant frequency, amplitude, and polorization of the vector are obtained. The conclusion is reached that normal daytime Pc's seem to occur in a small band centred around a dominant frequency. Two such dominant frequencies may occur simultaneously and the vectors can have different polarization. The amplitude and direction of a given Pc seems to follow a closed diurnal pattern reaching a maximum slightly before local noon.
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