Xontolite in a leucocratic rock intruded into the serpentinite in the southern part of the Sambagawa metamorphic terrane at Shiraki, Mie Prefecture occurs as colorless or palegreen colored veinlets with vitreous luster and transparency up to 2mm in width cutting veinlets of pectolite and vesuvianite in which Fe-chlorite occurs as a black-colored wall material. It shows parallel extinction to elongation and the sign of elongation is positiive. The refractive indices: α=1.584, β=1.584, γ=1.956 and γ-α=0.012. The specific gravity is 2.71 by the buoyancy method. X-ray powder diffraction shows that splitting is seen in the pair of (401)-(401), the peak for (401) of which is observed as a shoulder, becoming distinct with heat treatment up to 500°C. DTA-TG of the xonotlite shows endothermic reactions at 801°C (parawollastonite) and 1140°C (pseudowollastonite) and gives 5.15% loss of weight. The larger content of water may be responsible for the lower peak temperature than the previous data in the literature on DTA-TG curves.
The pectolite and vesuivanite also contain larger amount of water than the previously reported data by other authors.
The xonotlite from Shiraki appears to have been formed in the later stage of crystallization as precipitates from silicate solution with a lower temperature in the presence of abundant water.

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We studied petrographically and paleomagnetically the greenstone exposed in the MugiKamiaso area, Gifu Prefecture, central Japan. This greenstone is unmetamorphosed generally but propylitized weakly, and is appropriate for paleomagnetic researches. Various tests with respect to the magnetic stability revealed that the greenstone preserves reliable records of magnetization acquired, probably, at the time of eruption. Paleomagnetic measurements provided reasonable ground to us for concluding that the greenstone is not an assemblage of randomly-oriented blocks which were emplaced as debris flows or grain flows. The greenstone occasionally occurs by accompanying Permian limestone, but both of them intervene stratigraphically between Mesozoic strata. It is highly probable that they have migrated as exotic sliding sheets from somewhere and have been accreted to the Mesozoic unit. Based on the regional geologic and sedimentologic information from this area, some discussions are directed toward the possible pre-emplacement setting of the greenstone.

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On the south of Osaka Prefecture, the Sennan acidic pyroclastics and several types of granitic rocks of the Ryoke metamorphic belt are widely distributed. The Sennan pyroclastics had been considered to disappear on the east of the River Ushitaki, but the writers have found that they extend to the far east of the River Makio (Fig. 7). Among the granitic rocks some types are unconformably covered with the Sennan pyroclastics and other ones intrude the pyroclastics. Thus, the granitic rocks in this area have been divided into two groups, the older (Pre-Sennan granites) and the younger (Post-Sennan granites).

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K-Ar ages were determined on some metamorphic rocks from the Sanbagawa terrain. The ages obtained are mostly of Middle and Late Cretaceous (110-67 m. y.). This range may not indicate the age of the main stage of metamorphism, but may represent the age of uplifting of the metamorphic rocks. The complete interpretation remains to be solved in future.

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