2 0 0 0 OA 埼玉県小川町~東京都青梅市の寺院にある 石灰岩でつくられた近世の石造物
- 著者
- 松岡 喜久次 桑原 希世子
- 出版者
- 地学団体研究会
- 雑誌
- 地球科学 (ISSN:03666611)
- 巻号頁・発行日
- vol.75, no.2, pp.119-124, 2021-04-25 (Released:2021-06-30)
- 参考文献数
- 28
The Capitanian (Permian) radiolarians were found from a siliceous tuff block within volcaniclastic rocks in the Sumaizuku Unit of the Northern Chichibu Belt in the Kanto Mountains. The Sumaizuku Unit is composed of chaotic rocks consisting of exotic blocks of chert and mafic rocks in Jurassic clastic matrix. The rocks of studied area consist of limestone-basalt conglomerate, lime-sandstone, volcaniclastic rocks and chert. The volcaniclastic rocks are composed of clasts of basalt lava and volcanic glass accompanied with clasts of limestone, siliceous tuff and fragment of plagioclase. The clasts of siliceous tuff containing radiolarian tests are angular pebble to boulder. The siliceous tuff is regarded as blocks which were mixed in volcaniclastic rocks by slumping. We consider that the volcaniclastic rocks deposited immediately after Capitanian age, and this deposition formed on the lower flank of a seamount.