抄録
The 'Sueki' ancient pottery sites and the ruins of their kilns constitute the Minamihiki ruin group of kilns, the largest archaeological site of the "Big Four Ruins of Kilns in Musashi Province" in west Kanto Plain, that is densely scattered throughout the Iwadono Hills, Saitama Prefecture, Japan. The clay for 'Sueki' has been known to be derived from marine sedimentary rocks of this hill based on occurrence of fired marine siliceous sponge spicules from 'Sueki'. Fragments of 'Sueki' collected from the Shogunzawa 1A ruin of kilns in Ranzan Town and the Kawasaki site in Fujimino City yield the middle Miocene radiolarians. This age is the same with the depositional age of the Shogunzawa Mudstone Member of the Iwadono Formation. While fragments of 'Sueki' collected from the Osugi site in Ogawa Town and clay from Sue in Hatoyama Town contain the late Miocene radiolarians. This indicative age of radiolarians shows the same to that of the Hatoyama Sandstone and Mudstone Member of the Ohashi Formation. As the small fragments of 'Sueki' and a small amount of the clay for 'Sueki' examined in this study certainly yield radiolarians, both are considered to be derived from radiolaria-rich sedimentary rocks of the Shogunzawa Mudstone and Hatoyama Sandstone and Mudstone members.