The pelitic gneisses of the upper reach area of Tetori river in the Hida belt are characterized by low K₂O/(Na₂O+K₂O) mole ratio (0.2-0.3), low Al₂O₃/(CaO+Na₂O+K₂O) mole ratio (1.0-1.4), high Ca, and high Sr. These are common chemical features of most pelitic gneisses in the Hida belt.
     Alkali elements, Zr and Y contents of hornblende gneisses of this area show the characteristics of the continental island arc basalt-andsite. It coincides with the general alkali-rich nature of the basic gneisses and amphibolites in Hida belt.
     REE and HFS element concentration of the pelitic gneisses in the upper reach area of Tetori river generally agrees with those of average post-Archean shales, and is poor in Ni and Cr. Their REEs show prominent negative Eu anomaly. These features suggest lesser contribution of basic volcanic fragments.
     Compilation of Chinese and Korean data shows that pelitic metamorphic rocks in the Sino-Korean block are low in K₂O/(Na₂O+K₂O) mole ratio (0.2-0.9) and Al₂O₃/(CaO+Na₂O+K₂O) mole ratio (1.0-3.0), but those in Yangtze block and South Korea are high in K₂O/(Na₂O+K₂O) mole ratio (0.5-0.9) and Al₂O₃/(CaO+Na₂O+K₂O) mole ratio (1.5-3.5). This fact agrees with the long-lasting (Precambrian to Mesozoic) geochemical differences of granites between Sino-Korean block and Yangtze block. This suggests that the provenance of protolith of pelitic gneisses in the Hida belt may have been the Sino-Korean block.

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三都橋花こう岩体（8×8 km）は，領家変成岩中に定置して，約80 Maの放射年代を示す。主要な構成岩石は粗粒なホルンブレンド—黒雲母トーナル岩∼K₂Oに乏しい花こう閃緑岩であるが，カミントン閃石かアルマンディン質のざくろ石を伴う石英閃緑岩もある。岩体の周縁部では，ざくろ石—黒雲母花こう岩∼花こう閃緑岩からなる周縁相が発達し，その一部は変成岩を同化したものである。ほとんどすべての岩石は石灰質で，アルカリ—石灰指数は65に達する。カリに乏しく，高いFe/Mg比を示す。 Zrの含有量は高いが，Rbは低い（<50 ppm）。鉱物共生やその平衡関係から，この岩体は地下15 km以深に定置したものと推定され，低酸素分圧下で結晶作用を行った。微量元素についての変化図や稀土類元素のパターンから，黒雲母の分別や斜長石の集積があったと考えられる。モードや化学組成の変化は，おもに分別集積した斜長石と結晶粒間の液（intercumulus liquid）との比の変化として説明できる。この岩体の起源物質は，領家帯の下部地殻を構成する苦鉄質岩と考えられる。

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The Yudonosan volcano is a small stratovolcano belonging to the Chokai zone in northeastern Japan. The erupted rocks are mainly calc-alkaline quartz-biotite-hornblende-dacite and a subordinate amount of quartz-pyroxene-hornblende-andesite. In these rocks, two types of inclusions can be seen. Both are composed of mainly plagioclases, pyroxenes, and hornblendes, while grain sizes of minerals tend to be coarser in type 2 than in type 1.
     The mixing of felsic and mafic magmas, associated with the Yudonosan volcano, can be indicated by reverse zoning (An₃₀ core to An₇₈ rim) of plagioclase phenocrysts, clinopyroxene reaction rims around quartz, and dusty zones of plagioclase phenocrysts in host rocks. Most of the plagioclase, pyroxene, and hornblende phenocrysts have Na-rich, Fe-rich, and Si-rich cores, respectively. These phenocrysts were probably derived from the felsic magmas. Phenocrysts from mafic magmas were rarely found in host rocks. From pyroxene and hornblende phenocryst compositions in the host rocks, the temperature within the felsic magma chamber was estimated to have been 750-850°C, with the chamber location above the middle of the crust. Rim compositions of plagioclase phenocrysts varied, suggesting that the magma mixing was insufficient.
     Coarser grained plagioclases, pyroxenes, and hornblendes in type 2 inclusions show the same compositions as phenocrysts in the host rocks. While, finer grained plagioclases, pyroxenes, and hornblendes in type 1 inclusions are Ca-richer, Mg-richer, and Si-poorer than those phenocrysts in the host rocks. These features suggest that the type 1 inclusions were derived from the mafic magma, and type 2 were from the felsic one. It is likely that, in the crystallizing felsic magma chamber, small amounts of mafic magmas were supplied intermittently, and caused insufficient mixings and eruptions. Mafic magmas became the type 1 inclusions, while crystal-rich parts in the felsic magmas solidified to become type 2 inclusions.

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