Travertines in Japan

In this chapter, we describe several representative travertine sites in the Japanese islands. According to our extensive search, there are at least 30 hot springs that developed calcareous deposits (Fig. 7.1, see also Figs. 7.13 and 7.15). Many of them are simple localities having only a single onsen facility, and an example is Furofushi hot spring on northern coast of the Honshu Island (Fig. 7.1), where you can see the beautiful sunset on the Japan Sea. Hirokawara hot spring in Yamagata Prefecture is a relatively new geyser, and you have to drive 20 km on dirt road to reach there. Among the onsens listed on Fig. 7.1, only four locations, Masutomi, Shirahone, Arima, and Nagayu, have a large capacity and a wide facility for accepting many visitors. These onsens have also attracted many scientists for a study subject.