| Research Abstract |
In this study, we presented a great number of chemical data of volcanics, metamerphics and granitics including trace metal contents and REE contents. Tagiri indicated the following results in his papers. In the Hidaka Lower crust, first, S-type granitic magma formed in terms of batch melting of pelitic gneiss, segregated completely from host and ascended to upper crust. Next, I-type granitic magma formed in terms of partial melting of basic gneiss, segregated partially from host, ascended to upper crust and intruded into S-type granites. Moreover, Tagiri described LithoLogicaL column of continental crust which is very similar to a seismological column of continental crust.
Takahashi indicated three evolutions of magma-plumbing system beneath Fuji volcano based on a great number of geochemical analyses. A : the mantle diapirs with different source, signatures uprised successively. B : the convection within a single heterogeneous mantle diapir produced diversity of source basalt magmas. C : the melting of different portions of upper mantle is the cause for the diversity of source basalt magma. He also indicated chemical cat inhomogeneity of upper mantle.
Fujinawa studied two types of magma series, one is the tholeiitic magma series and the other the calc-alkaline one. Two magma series were derived from different sources. Tholeiitic magma series were derived from mantle origin primary basalt magma. However, calc-alkaline magma series are not only solely explained by fractional crystallization but also mixing of magnesian magma and assimilation of anatectic melt originated from lower crustal amphibolite.
|
