An examination of day-to-day and monthly mean positions of the electrojet axis in relation to the changes in the apparent solar declination, in the Indian equatorial region shows marked association between the two. For relatively quiet days, significant correlations are observed between the solar declination and each of the parameters, the northernSq focal latitude, the jet axis and the line of maximumSq(H). From the significant mutual association of these parameters, it has been suggested that the equatorial electrojet could be a part of the world-wideSq current system.

From the data of the geomagnetic survey of the Indian equatorial region conducted during 1971, it has been possible to deduce the subsurface magnetic anomalies at each survey station. The vertical magnetic anomaly profiles seem to reflect some of the known geological structures in the region. The association between magnetic anomalies and the deep-seated structures in this area emphasises the importance of future intensive studies.

The position of the dip equator (de) is worked out in the Indian region based on fairly close geomagnetic measurements made during a survey in the year 1981. Thede is located about 24 km south of its 1971 position along the 77·5°E meridian. Also, thede positions for the epochs 1971 and 1981 show closeness on the east coast of India when compared to its west coast positions. Thede positions inferred from the repeat observations since 1909 are used for estimating the pattern of migration and the results are discussed.