System and method for reconstructed wavefield inversion

A method for seismic imaging, the method comprising:

• forward propagating a source signature through an earth model of a subsurface structure to generate a forward-propagated wavefield in a time domain;
• generating a residual by comparing the forward-propagated wavefield to field data obtained by an array of seismic sensors at a plurality of seismic receiver locations, wherein the field data are responsive to reflection of the source signature propagating from the subsurface structure through a seismic medium;
• back propagating the residual through the earth model to generate a reconstructed source perturbation in the time domain;
• adding the reconstructed source perturbation to the source signature to generate a reconstructed source wavefield;
• forward propagating the reconstructed source perturbation in the time domain based on the earth model to generate a reconstructed wavefield perturbation and adding the reconstructed wavefield perturbation to the forward-propagated wavefield to generate a reconstructed forward-propagated wavefield;
• updating the earth model based on the reconstructed forward-propagated wavefield and the reconstructed source perturbation, wherein the forward propagating and back propagating are performed in the time domain;
• and
• generating a seismic image characterizing the subsurface structure, based on the updated earth model.

A non-transitory machine readable data storage medium having program code stored thereon, the program code executable on a computer processor to perform a method comprising:

• forward propagating a source signature through an earth model of a subsurface region, in a time domain to generate a forward-propagated wavefield;
• generating a residual by comparing the forward-propagated wavefield to field data acquired by an array of seismic sensors responsive to the source signature reflected from the subsurface region and propagating through a seismic medium;
• generating a reconstructed source perturbation by back propagating the residual through the earth model in the time domain and generating a reconstructed source wavefield by adding the perturbed source wavefield to the source signature;
• generating a reconstructed wavefield by forward propagating the reconstructed source perturbation through the earth model in the time domain and adding to the forward-propagated wavefield;
• generating an objective function by comparing the reconstructed wavefield to the field data and evaluating a wave equation error;
• updating the earth model by minimizing the objective function with respect to one or more seismic parameters characterizing the earth model of the subsurface region while the reconstructed source wavefield is held constant or kept unchanged;
• and
• generating a seismic image of the subsurface region based on the updated earth model.