Archaeomagnetic Study for the Past 2,000 Years in Southwest Japan

Abstract

To clarify the secular variation of the geomagnetic field in the Kinki District, about 2, 600 samples were collected from some 150 kilns and hearths excavated in the Kinki District and its vicinity. The age of these samples covers a time range from 100 A.D. to the present. As a result of the magnetic measurements of these samples, the secular variation of the geomagnetic field in the Kinki District was brought to light in detail in this time range. In the same time range, the positions of the virtual geomagnetic north pole were calculated by using the values of the declination and inclination of the geomagnetic field thus obtained. The aspect of the secular variation of the virtual pole position seems to show that the movement of the virtual pole consists of two kinds of motion, that is, one is a basic counter-clockwise rotation of the period of about 1, 500 years and the other is three clockwise rotations of the period of about 500 years.