1981 Volume 31 Issue 168 Pages 311-320
Jurassic and Cretaceous granitoids are compared in the two areas. The Jurassic Daebo granitoids are dominantly composed of the ilmenite-series and are different from the Jurassic Funatsu granitoids in the Japanese side. The Cretaceous granitoids in the peninsular interior are of the ilmenite-series and weakly magnetic magnetite-series. The cretaceous granitoids of the Gyeongsang basin are predominantly magnetite-series granitoids with no clear separation in the distribution of two types of granitoids, whereas the oceanic side of the ilmenite-series and the marginal sea side of the magnetite-series pair is distinct in the similar volcano-sedimentary basin in the Japanese side.
The Gyeongsang basin is essentially a tungsten province and the wolframite deposits are generally associated with scheelite and molybdenite. These minerals occur separately in the Japanese side. The split-off part of the Gyeongsang basin has not been observed in the northern Kyushu and the western Chugoku districts. It is suggested that magmatism of the Gyeongsang basin occurred in a stable continental margin environment successive to the development of subsided basin in a tensional tectonic setting, whereas that of the southwestern Japan occurred in a floating island arcs where parallel lineaments were developed. The southwestern Japan may have been located at some distance from the Gyeongsang basin during the Cretaceous or Paleogene time.
