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The Misaki limestone of western Shikoku, belonging to the Sambagawa crystalline schists, occurs at the southern wing of an anticlinal structure and shows a monoclonal structure at the exposures. A sch...istosity and a lineation develop remarkably in the limestone. The Kohsa limestone occurs in the Higo gneiss area of central Kyushu. It consists of some lenticular rock bodies and is considered to have undergone the Ryoke metamorphism. Most calcite grains in both of the limestones show visible {0 1 1 2} lamellae in thin section, and the many lamellae are twinning on {0 1 1 2}. Calcites in the Misaki limestone show preferred orientation. The results of petrofabric analyses show that crystallographic c axes of calcites concentrate nearly perpendicular to the schistosity, and that the most effective direction of compression axis which has induced the twin gliding on {0 1 1 2} is parallel to the schistosity and perpendicular to the lineation. Seven specimens of the Misaki limestone and eight ones of the Kohsa limestone were chemically analyzed, and the lattice constants of calcites were obtained by a least squares method from X-ray powder data. The results show that each specimen contains less than 1. 5 mole % MgCO_3+FeCO_3+, and that there are some differences in the lattice constants between the observed values and the values expected from their chemical compositions. These data are considered to indicate that each limestone contains a residual strain (stress) caused by deformation.show more
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