The Effect on Micropulsations of a Localized Earth Conductivity Anomaly

The effect on the surface magnetic micropulsation fields of a localized conductivity anomaly is studied. It is found that, whereas the largest variations in the horizontal component occur over the anomaly, those of the vertical component occur at a distance to either side, the distance depending on the depth of the anomaly. The frequency most affected is also found to be a function of the depth of the anomaly.