Study on twilled structure-Superimposed deformation in the Shimanto Belt of the Ryukyu Islands-

斜纹构造是指被两个不同方向的断层包围的块体结构，每个块体的层理或片理的方向分别代表不同的方向，如斜纹布。该构造在冲绳-吉马和托西市发现，晚渐新世完成了NE-SW向的褶皱和断裂系统，晚第四纪与NW-SE向的断裂叠加，形成了孪生构造。每个地块都有穹隆和盆地构造，反映了叠加变形。以卡约组砂岩的石英增益为应变标志，进行了三维应变分析。然而，结果并不令人满意，因为没有显示应变场中的叠加变形，而只是显示了士兵过程中的Seak变形。

Twilled structure signifies a block structure bounded by faults of two different directions and the orientation of bedding or schistosity of each block represents different direction respectively such as twilled cloth. The structure is discovered in the Okinawa-jima and Tokasiki-jima.The fold and fault system of NE-SW direction had been accomplished in the late oligocene time has been superimposed by the faulting of NW-SE direction in the late quaternary producing the twilled structure. They have also dome and basin structure in each block suggesting a superimposed deformation.Three dimensional strain analysis have been carried out using quartz gains of the sandstones from the Kayo Formation as strain marker. The result is however, not satisfied because the superimposed deformation in the strain field is not revealed but a seak deformation during the soldification is only shown.