At the same outcrop near Yokokawa, Abukuma metamorphic terrane, occur high-grade lateritic and calc-silicate rocks. The lateritic rocks constitute a discrete block enclosed within calcite marble, whereas the calc-silicate rock is a thin layer intercalated between calcite marble and pelitic-psammitic gneiss.
Textures and compositions of minerals in the lateritic rocks suggest high-temperature loading and subsequent unloading. The characteristic mineral assemblages before loading, at the peak of loading and after unloading are hercynite+sillimanite, corundum+almandine and hercynite+sillimanite, respectively. The hercynite+sillimanite assemblage before loading is well preserved as inclusions in corundum and almandine porphyroblasts, and is texturally distinct from the similar mineral assemblage formed after unloading.
On the other hand, the calc-silicate rock shows no evidence for such a P-T history, and has mineral assemblages stable at high temperatures and low pressures, such as anorthite+wollastonite. In addition, decomposition of CO₃-scapolite to anorthite and calcite suggests recrystallization upon cooling, which may have taken place coevally with the emplacement of the nearby Cretaceous plutons. The occurrence of wollastonite with calcite and quartz only in the major part of the calc-silicate rock suggests that X_co2 of the fluid phase in the major part was lower than that in the marginal part (next to pelitic-psammitic gneiss) over a distance of a few mm during metamorphism.

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The δD values and contents of H₂O (OH) extracted from zinnwaldite and lepidolite, and also from muscovite and biotite in the two Mesozoic granitic masses of the southeastern China were measured. The Li₂O and F contents of these minerals were also determined. The δD value of OH from the lithium-bearing micas is very high, and their water content (OH) is low (< 1.00 wt %) and F content high (> 6.00 wt %). The relationship between Li₂O and F contents is positive, but that between Li₂O and H₂O contents is negative. The relationship between the δ D value and Li₂O content is positive, and accordingly negative between δ D value and H₂O content. Some proposals were made for the high δ D value of lithium-bearing micas.

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The path of fractional crystallization in the magma reservoir is different in the Akagi and Hotaka volcanoes, both of which are frontal volcanoes of northeastern Japan arc. Estimated magmatic temperature decreases by about 130°C from 1050 to 920°C during the compositional change of liquid from 54 to 70 wt % SiO₂ in the Akagi volcano. In the Hotaka volcano, however, the temperature decreases by only about 60°C from 1050 to 990°C during the same compositional change. This difference is also reflected on the early appearance of hornblende and common occurrence of groundmass hypersthene in the Akagi volcano. Al₂O₃, content of the magma of the Akagi volcano is higher than that of the Hotaka volcano. These differences can be well accounted for by the different water contents in the parental magmas; the magma of the Akagi volcano had a higher water content.
They also show different chemical trends on FeO^*/MgO-SiO₂ variation diagram; the constant FeO^*/MgO ratio with increasing SiO₂ in the Akagi volcano in contrast to the iron-enrichment trend in the Hotaka volcano. Least-squares mixing calculations show that the different iron-enrichment is caused by the different proportions of plagioclase in the fractionated minerals; higher plagioclase proportion in the Akagi magma than in the Hotaka magma.

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