"Proto-Japanese Islands" estimated by detrital minerals in Cretaceous sediments

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The geologic belts in the Japanese Islands were rearranged by movement of Japan Sea formation in middle Cenozoic. I have conduced dating of monazite and zircon for Cretaceous shallow- and non- marine sediments and basement rocks. I succeeded to decide the precision sedimentary age of the Sasayama Group. In addition, detrital monazites from the Himenoura Group indicated a possibility that Cretaceous granitoids were scarce in the provenance of the group. Exploration of Cretaceous accretionary complex is conducted in the Tenryu area of the Sanbagawa Belt. Although the area was thought to be the contact of the "Sanbagawa meta-AC sensu stricto" and the "Shimanto meta-AC", the result of my study clearly indicate that both of the unit in the area originate from Late Cretaceous accretionary complexes.