By using 3-D finite element method,author studied and calculated the interaction between the source fault and the deep upright fault on the same plane before,during and after a strong earthquake and the near field transverse fault which is locked because of the dislocation of the deep upright fault. The following results are obtained:(1)Before a strong earthquake occurs,the deep fault units under the adjustment units have higher shear strain level with the result that the deep fault has a diapirism at the bottom of the seismic source fault during the earth-quake,namely,the deep fauIt units under the adjustment units first reach the fracture limit and split.(2)The adjustment units at the ends of earthquake source and transverse fault with the creeping capacity might prevent the earthquake faults from splitting.(3)A strong earthquake fault's splitting spreads to transverse fault, which could not make the transverse fault locked but may make the deep fault splitting spread. The shallow transverse fault is twisted and locked when the deep fault's splitting spreads to the bottom of the shallow transverse fault.Meanwhile,the seismometry quota concerned with the locked transverse fault appears, this quota is the very small earthquake belt which is controlled by the deep fault.(4)The resigning capacity of the adjustment units is limited during a strong earthquake,it may give rise to strong aftershocks the ends of the source fault.