关键词: 交叉断层, 交替活动, 块体活动, 物理场观测

Abstract: Unstable events taking place alternately along two intersecting faults is proved by physical modeling. Two intersecting faults promote and restrain each other during deformation. One fault may make the other be locked for strain accumulation and may trigger slip along it. Slip rate, net slip and the numbers of unstable events depend on the orientation of the fault with respect to the principal stress axes. The slips along different fault segments show both translation and rotation of the fault block surrounded by them in the experiment. The affected area of unstable event is different for events occurred on different parts of the sample and it is wider for the event along the fault with high normal stress. Small precursory events usually occur before strong instability involving the intersecting faults. In fact, the movement of the fault block in the deformation field controls the alternate slips of intersecting faults.

Key words: Intersecting faults, Alternate slip, Block movement, Observation of physical field