@article{oai:niigata-u.repo.nii.ac.jp:00003193,
 author = {野田, 篤 and 利光, 誠一 and 栗原, 敏之 and 岩野, 英樹},
 issue = {2},
 journal = {地質学雑誌, 地質学雑誌},
 month = {Feb},
 note = {上部白亜系の和泉層群は横ずれ堆積盆を西から東へ埋積した地層と言われているが，四国の西部と東部とでは岩相や地質構造に違いがあり，堆積盆の埋積過程やテクトニクスが異なっていた可能性がある．今回，四国中央部の新居浜地域の和泉層群を調査し，北縁相の楠崎層と主部相の磯浦層・新居浜層の3つの新しい地層名を定義した．新居浜層に挟在する珪長質凝灰岩を用いたフィッション・トラック年代は79.1±2.2 Maを示した．また，新居浜層の泥岩から産出した放散虫化石群集は，前期－中期カンパニアン階のDK群集帯に対比された．これらの結果は新居浜層の堆積年代が中期カンパニアン期であり，四国西部（松山地域）に分布する同層群とほぼ同時期に堆積したことを示唆している．本地域の和泉層群の岩相や地質構造は四国西部と東部に見られる同層群の両方の特徴を持っており，その堆積盆形成・埋積プロセスの過渡期に堆積した地層であると考えられる．, The Izumi Group, which occurs from western Shikoku to the Izumi Mountains, Kii Peninsula, comprises sediments deposited in a strike-slip basin during the Late Cretaceous. Some differences exist in the lithostratigraphy and geological structure of the group where it occurs in western and eastern Shikoku; consequently, outcrops in central Shikoku may record evidence of the transition between the two areas. We conducted stratigraphical and geochronological surveys as part of compiling the "Niihama" geological map, and defined the following new formations: the Kussaki, Isoura, and Niihama formations. Fission-track dating of felsic tuff beds in the Niihama Formation yielded an age of 79.1±2.2 Ma. The radiolarian assemblages within mudstone of the Niihama Formation are DK assemblages, corresponding to the early-middle Campanian. The combined age data indicate a middle Campanian age for deposition of the Niihama Formation. The present results suggest that the Izumi Group was simultaneously deposited in western and central Shikoku. The lithology and geological structure in the study area are comparable with those in western and eastern Shikoku, indicating that the analyzed rocks represent strata deposited during a transitional stage of basin development and basin fill.},
 pages = {99--113},
 title = {愛媛県新居浜地域における和泉層群の層序と堆積年代},
 volume = {116},
 year = {2010}
}