Eocene calcareous nannofossils and dinoflagellate cysts from the Iwaya Formation in Awajishima Island, Hyogo Prefecture, southwest Japan, and their geologic implications.
Eocene calcareous nannofossils and dinoflagellate cysts from the Iwaya Formation in Awajishima Island, Hyogo Prefecture, southwest Japan, and their geologic implications.
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日本西南部兵库县淡路岛岩屋组的始新世钙质超微化石和甲藻包囊及其地质意义。
DOI：
10.5575/geosoc.106.379
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
T. Matsubara
中科院分区：
文献类型：
--
作者：
Y. Yamamoto;H. Kurita;T. Matsubara
利用钙质纳米化石和鞭毛藻囊，研究了浅岛“中新世”岩屋组的地质年代。钙质纳米化石区系表明生物带NP 17 ~ NP 20或CP 14b ~ CP 15b，时间为中始新世晚期~晚始新世。鞭毛囊组合也显示出大致相同的年龄。结果表明，岩屋组是始新统-渐新统神户群的组成部分。在濑户内海东部沿海地区的“濑户内中新世系列”中发现了与岩屋组相似的软体动物组合。该地区“中新世”的软体动物区系和地层对比也应在精确的地质年代学资料的基础上重新进行研究。
Geologic age of the "Miocene" Iwaya Formation in Awajishima Island is examined by means of calcareous nannofossils and dinoflagellate cysts. Calcareous nannofossil flora indicates biozone NP 17 to NP 20 or CP 14 b to CP 15 b and a late Middle Eocene to Late Eocene age. The dinoflagellate cyst assemblages also show approximately the same age. These results reveal that the Iwaya Formation is the constituent of the Eocene-Oligocene Kobe Group.Molluscan assemblages resembling those from the Iwaya Formation have been known from the "Setouchi Miocene Series" in the coastal area of the eastern Seto Inland Sea. Molluscan fauna and stratigraphic correlation of the "Miocene" in this area should also be re-examined on the basis of precise geochronologic data.