A method of estimating lateral positioning uncertainties of a seismic image is performed at a computer system. The computer system receives a velocity model, the velocity model including a plurality of base velocity values used for generating the seismic image, each base velocity value having a low limit and a high limit. The computer system derives a plurality of lateral velocity gradient uncertainties from the velocity model and generates multiple lateral velocity gradient profiles, each lateral velocity gradient profile including a random realization of the plurality of lateral velocity gradient uncertainties. The computer system calculates perturbation raypaths originating from a surface point of the seismic image based on the velocity model and the multiple lateral velocity gradient profiles and estimates a lateral positioning uncertainty for a target location at a predefined depth of the seismic image based on lateral distributions of the perturbation raypaths at the predefined depth.