@article{oai:mue.repo.nii.ac.jp:00000807, author = {川村, 寿郎 and 猪瀬, 文野 and 佐藤, 奈月 and 檀原, 徹 and 岩野, 英樹}, journal = {宮城教育大学紀要, Bulletin of Miyagi University of Education}, month = {Jan}, note = {Mineral specimens occurring around the Aobayama Hill have been utilized as scientific study objects, also as familiar geology-teaching materials in the Sendai area. We investigate the background geology of their occurrences including stratigraphic horizons, depositional conditions, and radiometric age. Large crystals of anorthite and augite, originally produced as crystal bombs of volcanic eruptions, are collected from a tuff breccia bed of the lowest part of Upper Miocene Mitaki Formation which unconformably covers the Nashino Formation. Large pseudomorph specimens of high-quartz are obtained from matrix-supported conglomerate, tufffaceous sandstone or pebble-containing mudstone beds, which strata overlie the Mitaki Formation. Zircon grains from the high-quartz horizon are dated to 8.0±0.7 Ma as fission-track age by the LA-ICP-MS method combined with the U-Pb dating. The strata including high-quartz horizon beds, often showing chaotic or dipping, are covered by a flat bed of clast-supported conglomerate underlying the Pliocene Tatsunokuchi Formation. They belong not to the Pliocene Kameoka Formation as a conventional thought, but probably to the Upper Miocene Shirasawa Formation or the upper part of Nashino Formation, which two formations have been regarded as contemporaneous to the Mitaki Formation. Possibly, high-quartz have been derived from pumice tuff of the Nashino Formation which had been exposed in adjacent area at that time.}, pages = {167--176}, title = {青葉山周辺から産する鉱物標本の産出層準- 仙台地域の地学教材の基礎資料 -}, volume = {53}, year = {2019} }