1�� College of Geo- Exploration Science and Technology��Jilin University��Changchun 130026��China; 2�� College of Geographic Space Information��Information Engineering University��Zhengzhou 450052��China

Demigration refers to directly applying a specific imaging technique to a migrated section�� It is ap- plied primarily to seismic data mapping�� In a previous research study��a time- efficient implementation techno- logy of demigration was expounded�� In the present study��the Fast Marching Method (FMM) used for travel- time computation in the isochrone- stack demigration�� is developed�� Furthermore�� other key techniques (such as selection of aperture and antialiasing filtering factor) are analyzed in detail�� Besides��the detail implementation method and program flow are given��which is shown their good computational efficiency and high- quality demi- gration effect�� This implementation technique is illustrated with both the V(z) model and Marmousi model�� It provides a basic method for implementing demigration in the application of seismic data mapping��