Fig. 1From: A record of the upper Olduvai geomagnetic polarity transition from a sediment core in southern Yokohama City, Pacific side of central JapanLocation maps of the study site. a Tectonic plates under the Japanese Islands (modified from Fig. 1 of Seno and Takano 1989). b Distribution of the Kazusa Group in the southern Kanto region (compiled from Mitsunashi and Suda 1980; Mitsunashi et al. 1980; Unozawa et al. 1983; Eto 1986; and Sakamoto et al. 1987). c Locality map showing the core sites (solid stars) plotted on a 1:25,000 scale topographic map published by the Geospatial Information Authority of JapanBack to article page