Precise structural analysis of the Shimanto accretionary complex in Kyushu, southwest Japan.

对九州岛西南部岛曼都带和德岛岛的地质构造进行了研究。在北松地区，玄武岩熔岩、硅质岩和泥岩层形成了叠瓦状结构。萨摩半岛的Yaseo地区产有岛曼托带中的蛇纹岩。在长约100×50m和200×70m的范围内，出露了两个主要蛇纹岩岩体，覆盖了近水平边界的西倾砂岩和泥岩层，在南松地区乔雅山地区，泥岩和砂岩层普遍向西倾斜，并向西倾斜。德岛岛中部的地质由泥质-砂砾岩片岩、花岗岩侵入岩和零星蛇纹岩组成。泥质片岩中分布有北西向低倾角的蛇纹岩透镜体。厚达20厘米的暗色纹理出现在德岛西部秋里格米河河口的泥质和砂质片岩中。矿脉中充满了大小不一的围岩碎片和细小的颗粒。

Geological structures of the Shimanto Belt in southwestern Kyusyu and Tokunoshima Island have been investigated. In the Hokusatsu district, layers of basaltic lava, chert and mudstone form imbricate structure. The Yaseo area in the Satsuma Peninsula carries one of the serpentinite occurrences in the Shimanto Belt. Two majorserpentinite bodies are exposed in the areas extending about 100 x 50 m and 200 x 70 m.These overlie west-dipping layers of sandstone and mudstone with subhorizontal boundaries.In the Choyasan area of the Nansatsu district, layers of mudstone and sandstone generally dip west with westerly younging. Geology of the central part of Tokunoshima Island is composed of pelitic-psammitic schsits, granitic intrusive rocks and sporadic serpentinite. Lenticular bodies of serpentinite dipping northwest in low angles are distributed in the pelitic schist. Dark-shaded veins with up to 20 cm thick appearin the pelitic and psammitic schists at the mouth of Akirigami River in western Tokunoshima. Fragments of the country rocks in variable sizes and fine-grained particles fill the veins.