{"title":"茨城県大子町に露出する中新統内大野層の石灰質ナノ化石年代","authors":"Masayuki UTSUNOMIYA, Jun HOSOI","doi":"10.9795/bullgsj.74.4_179","DOIUrl":"https://doi.org/10.9795/bullgsj.74.4_179","url":null,"abstract":"茨城県大子町に露出する中新統内大野層の泥岩について石灰質ナノ化石群集に基づく堆積年代の検討を行った.得られた試料のうち4地点5試料から石灰質ナノ化石の産出が認められ,それらはいずれも石灰質ナノ化石帯CN3もしくはCN4帯を示し,堆積年代は17.65 – 13.60 Ma(前期~中期中新世)の年代範囲内と考えられる.これらの結果は既存研究による火砕岩類の放射年代や珪藻化石年代と整合的である.","PeriodicalId":491338,"journal":{"name":"Chishitsu chosa kenkyu hokoku","volume":"17 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0