Fig. 4

3-D background stress pattern in the Kyushu island. The stress pattern at depths of (a) 5 km, (b) 10 km, and (c) 15 km. The stress pattern is represented with a lower hemisphere projection of focal spheres, where two nodal planes are maximum shear stress planes. The color scales in the background show uncertainties E for the stress pattern (see text). The stars and dashed lines are the same as in Fig. 3. The white lines show active faults