抄録
Near the junction of two arc systems, the state of stress within the earth's crust often appears to differ from the regional trend. The internal deformation of the continental plate at arc-arc junctions is probably controlled by geometrical configurations and the forces acting on the plate edges. If forces acting on the two neighbouring plate boundaries which intersect at a junction are not parallel to each other, convergence (or divergence) or shearing would take place at the junction. At a plate edge, four types of force (or displacement) can be assumed, whose direction is constrained by the strike of the edge. Thus four types of deformation can be expected within the continental plate near an arc-arc junction. One of these four basic types appears to be dominant in the real earth, probably because of the limitation on possible combinations of force (or displacement) types acting on the two neighbouring plate boundaries. The anomaly in the state of stress found near the junctions of the Kurile and Japan arcs and of the Aleutian and Kamchatka arcs may be related to a shearing force acting on the obliquely converging plate boundaries.
