The last appearance datum of the radiolarian Kilinora spiralis is recorded above the first appearance datum of the ammonite Ataxioceras (A.) kurisakense in the Todoro Section of the Kurisaka Formation, Southern Kurose...The last appearance datum of the radiolarian Kilinora spiralis is recorded above the first appearance datum of the ammonite Ataxioceras (A.) kurisakense in the Todoro Section of the Kurisaka Formation, Southern Kurosegawa Terrane, Shikoku, SW Japan. The constraint by ammonite age prolongs the range of the Kilinora spiralis Zone, a remarkable Jurassic radiolarian zone in Japan-NW Pacific region, into the lower Kimmeridgian. The direct correlation of the Kilinora spiralis zone with the Late Jurassic ammonite faunal succession in the Kurisaka Formation will provide a clue to the still pending chronological difference between European and North American radiolarian zones.展开更多
The Carboniferous conodont faunal succession of the lower part of Ko-yama Limestone Group was studied.The confirmed upper Visean-lower Moscovian lithostratigraphy of the group is characterized by the clastic carbonate...The Carboniferous conodont faunal succession of the lower part of Ko-yama Limestone Group was studied.The confirmed upper Visean-lower Moscovian lithostratigraphy of the group is characterized by the clastic carbonates with common association of the basaltic pyroclastics and some intercalation of spicular chert beds.The faunal succession of Gnathodus semiglaber(upper Visean),Gnathodus praebilineatus-Lochriea multinodosa(upper Visean),Lochriea ziegleri-Gnathodus girtyi girtyi s.l.(lower Serpukhovian),Neoganthodus symmetricus-Idiognathodus primulus(middle-upper Bashkirian),and Idiognathoides convexus-Gondolella clarki(lower Moscovian) faunas,appears in concordance with the lithostratigraphic order.The faunas are correlative with those from the conodont zones of the Hina,Atetsu,Akiyoshi and Omi limestone groups in the Akiyoshi Belt.The Visean/Serpukhovian boundary of the section was recognized by the FAD of Lochriea ziegleri.展开更多
文摘The last appearance datum of the radiolarian Kilinora spiralis is recorded above the first appearance datum of the ammonite Ataxioceras (A.) kurisakense in the Todoro Section of the Kurisaka Formation, Southern Kurosegawa Terrane, Shikoku, SW Japan. The constraint by ammonite age prolongs the range of the Kilinora spiralis Zone, a remarkable Jurassic radiolarian zone in Japan-NW Pacific region, into the lower Kimmeridgian. The direct correlation of the Kilinora spiralis zone with the Late Jurassic ammonite faunal succession in the Kurisaka Formation will provide a clue to the still pending chronological difference between European and North American radiolarian zones.
文摘The Carboniferous conodont faunal succession of the lower part of Ko-yama Limestone Group was studied.The confirmed upper Visean-lower Moscovian lithostratigraphy of the group is characterized by the clastic carbonates with common association of the basaltic pyroclastics and some intercalation of spicular chert beds.The faunal succession of Gnathodus semiglaber(upper Visean),Gnathodus praebilineatus-Lochriea multinodosa(upper Visean),Lochriea ziegleri-Gnathodus girtyi girtyi s.l.(lower Serpukhovian),Neoganthodus symmetricus-Idiognathodus primulus(middle-upper Bashkirian),and Idiognathoides convexus-Gondolella clarki(lower Moscovian) faunas,appears in concordance with the lithostratigraphic order.The faunas are correlative with those from the conodont zones of the Hina,Atetsu,Akiyoshi and Omi limestone groups in the Akiyoshi Belt.The Visean/Serpukhovian boundary of the section was recognized by the FAD of Lochriea ziegleri.
