1988 年 40 巻 6 号 p. 703-714
Paleomagnetic analysis was made on 36 lava flows and dykes of different ages distributed in Hiva-Oa Island, the Marquesas Islands (9.7°S and 139.0°W) in an attempt to study the geomagnetic paleosecular variation. K-Ar ages of samples range from 2.74m.y. to 1.63m.y. The present rotation axis is contained within the 95% confidence limit of the mean VGP (88.1°N and 117.9°W). The angular dispersion of 32 poles is 13.8° with respect to the rotation axis, and its upper and lower confidence limits are 16.6° and 11.8°, respectively. These values are consistent with the values of the global trend and the values predicted by secular variation models. Low secular variation as reported in the Hawaiian Islands is not observed in the Marquesas Islands.