A new secular variation curve for South Kyushu, Japan, and its application to the dating of some lava flows

The remanent magnetization of lava and pyroclastic flows from five dated volcanoes in Kagoshima Prefecture and Nansei Islands were measured. Alternating field and thermal demagnetization experiments reveal that specimens from these lava and pyroclastic flows preserve a stable remanent magnetization. The site mean directions of 55 sampling sites were corrected for the local magnetic declination and inclination values measured using a fluxgate type magnetometer at each locality. A new secular variation curve for South Kyusyu is established and applied for the age determination of some lava flows with unknown ages