Paleomagnetic and rock-magnetic measurements were performed on the GS-SB-1 core of 350.2 m long drilled at Shobu Town, Saitama Prefecture, central Kanto Plain, Japan. 493 and 16 samples were taken from the core for progressive alternating field and thermal demagnetization experiments. Approximately 95 % of the samples have a stable remanent magnetization component.The core between 0 and 266.755 m in depth yielded a normal polarity, while between 276.9 and 350.2 m in depth was a reversed polarity. The reversal between 266.755 and 350.2 m in depth corresponds to the Matuyama-Brunhes polarity transition.
