日本列島の基盤構造と活断層の形成位置との関係に関する基礎的研究

为了证明活动断裂与基底构造的关系，特别是。研究并分析了构造隆升为里奥克变质带的深部地壳剖面的剪切面，以及明显叠加在逆冲断层上的活动断裂系统。研究区域是八幡町-大岛。1)在矢滨-大岛的高变质逆冲片岩中，花岗闪长质片麻岩中广泛发育伪石脉，集中在3个脆性断裂带。：片麻岩在伪毛石形成之前经历了两个阶段的韧性剪切和一个阶段的脆性剪切，在伪毛石形成之后经历了一个阶段的韧性剪切和一个阶段的脆性剪切。伪水晶石脉与Y、R1、P等尖锐的滑移面相联系，与滑移面呈大角度。主滑面(Y)平行于第一期糜棱岩片理，切出极窄的碎裂脉。逆冲片底部的伪水晶石脉部分呈延性变形；岩脉内的乡村岩石碎块变形为透镜状，石英优选晶格取向，玻璃重结晶为亚显微云母和不透明矿物，平行于乡村岩石的剪切面取向。2)在里奥克带基部，尖锐的滑面与强糜棱岩片理普遍平行。日本中部和田-三久保地区暴露的地壳深层剖面。基底逆冲缓慢地向西北倾斜，并被一个被称为中构造线的活动断层切断。活动断裂与前述理奥克带的逆冲断裂或脆性断裂无关。3)该结论也得到了川内地区活动性断层的黄金示踪的支持。它是MTL活动断层系统的一部分。活动断裂被认为是在里奥克带的基底逆冲中，但在本地区并非如此。少

In order to prove the relationships between active faults and the basement strcutures, especially. ancient ductile and brittle faults, we have investigated and analyze shear planes in a deep crustal section tectonically uplifted as the Ryoke metamorphic belt, and an active fault system apparently superposed on the thrust fault of the crustal section. The study areas are 1) Yawatahama-Oshima island. 2) Wada-Misakubo region of the Ryoke metamorphic belt, and 3) Kawauchi, south to Matsuyama.1) In the high-grade metamorphic thrust sheet of the Yawatahama-Oshima island, pseudotachylite veins are extensively developed in granodioritic gneisses, concentrated in three zones of brittle fault. : The gneisses have suffered two stages of ductile shearing and one stage of brittle before pseudotachylite, and one stage each of ductile shearing and of brittle shearing after pseudotachylite. The pseudotachylite veins associate with sharp slip planes such as Y, R1 and P, and fructures high angle to the … More slip planes. The main slip planes (Y) are parallel to the pre-existing mylonite foliation of first stage, and cut very narrow cataclastic veins. At the base of the thrust sheet, pseudotachylite veins are partly deformed in a ductile manner ; country rock fragments within veins deform to lenticular shape, quartz has preferred lattice orientations and glass are recrystallised to submicroscopic mica and opaque minerals, oriented parallel to shear planes in country rocks.2) Sharp slip planes are generally parallel with strong mylonite foliations in the basal part of the Ryoke belt. an exposed deep crustal section, in the Wada-Misakubo area, central Japan. The basal thrust gently dips northwestward, and cut by an active fault, known as the Median Tectonic Line. The active fault is not related to the foregoing thrust or brittle faults in the Ryoke belt.3) The conclusion is also supported by geld tracing of an active fault in the Kawauchi area, south to. Matsuyama, which is a part of the MTL active fault system. The active fault has been considered to marge into tha basal thrust of the Ryoke Belt, but it is not the case in this area. Less