Considering the third dimension in stress-triggering of aftershocks: 1993 Klamath Falls, Oregon, earthquake sequence

Dip slip on a fault of finite dimension produces a static stress change tha t varies considerably in 3-D. The 1993 Klamath Falls (Oregon, USA) earthqua ke sequence shows a shallow, off-fault cluster of aftershocks with mixed di p-slip and strike-slip focal mechanisms. Modeled static stress change and l ocation of aftershocks show a misleading correspondence when viewed in the customary 2-D presentation. Full 3-D analysis shows that shallow right-late ral slip is consistent with the local stress perturbation following the dip -slip main shocks.