抄録
The Nakanotake metagabbroic mass had been considered to be a massive rock body whose interior structure had not been affected by tectonic events. Our study, however, found three schist layers which had undergone remarkable ductile shear deformation from the Nakanotake metagabbroic mass. This fact implies that the Nakanotake metagabbroic mass is made of piling tectonic slices bounded by some schist layers as a ductile shear zone. The pelitic schist layers appear to be conjunctive zones, resulted from a concentration of tectonic strain of piling tectonic slices, because minor deformed structures such as intrafolial and sheath folds developed only in the pelitic schist. In the Katashina Belt, the piling tectonic slice structure has not been found, but the discovery of such a structure would suggest that the Katashina Belt may consist of some piling tectonic slices thrust over the Ashio Belt.
