College of Geo--exploration Science and Technology��Jilin University��Changchun 130026��China

Estimation of converted wave residual statics is a nonlinear problem�� In order to estimate converted wave residual statics accurately��we combine two nonlinear optimization methods��the particle swarm optimization and simulated annealing��into a new algorithm PSOSA�� To test its validity��we build a single-layer model��achieve the synthetic seismogram with residual statics��estimate residual statics by using PSOSA and correct the origin synthetic seismogram with achieved statics�� The result shows good continuity of stack section and good single shot gather after static correction and small error of the statics�� Those prove that the PSOSA can estimate converted wave residual statics accurately��