Method and system for seismic denoising using omnifocal reformation

A non-transitory computer readable medium storing instructions executable by a computer processor, the instructions comprising functionality for:

• receiving a seismic dataset for the subterranean region of interest;
• obtaining a geological dip model for the subterranean region of interest;
• determining a set of input seismic gathers from the seismic dataset;
• selecting a central seismic gather and a set of neighboring seismic gathers in a vicinity of the central seismic gather from the set of seismic gathers;
• determining a set of dip-corrected neighboring seismic gathers by:
• dividing the set of neighboring seismic gathers into a plurality of seismic gather windows,
• determining a local geological dip for each seismic gather window from the geological dip model,
• determining an applicate shift for each of the plurality of seismic gather windows based, at least in part, on the local geological dip,
• determining a plurality of shifted gather windows by shifting at least some of the plurality of seismic gather windows along an applicate axis based on the applicate shifts, and
• forming the set of dip-corrected neighboring seismic gathers by combining the set of shifted gather windows;
• determining a noise-attenuated central seismic gather by combining the dip-corrected neighboring seismic gathers and the central seismic gather;
• and
• forming the image of the subterranean region of interest based, at least in part, on the noise-attenuated central seismic gather.

A system for forming an image of a subterranean region of interest, comprising:

• a seismic source to emit a radiated seismic wave;
• a plurality of seismic receivers for detecting and recording an observed seismic dataset generated by the radiated seismic wave;
• and
• a seismic processor configured to:
• receive a seismic dataset for the subterranean region of interest;
• obtain a geological dip model for the subterranean region of interest;
• determine a set of input seismic gathers from the seismic dataset;
• select a central seismic gather and a set of neighboring seismic gathers in a vicinity of the central seismic gather from the set of seismic gathers;
• determine a set of dip-corrected neighboring seismic gathers by:
• dividing the set of neighboring seismic gathers into a plurality of seismic gather windows,
• determining a local geological dip for each seismic gather window from the geological dip model,
• determining an applicate shift for each of the plurality of seismic gather windows based, at least in part, on the local geological dip,
• determining a plurality of shifted gather windows by shifting at least some of the plurality of seismic gather windows along an applicate axis based on the applicate shifts, and
• forming the set of dip-corrected neighboring seismic gathers by combining the set of shifted gather windows;
• determine a noise-attenuated central seismic gather by combining the dip-corrected neighboring seismic gathers and the central seismic gather;
• and
• form the image of the subterranean region of interest based, at least in part, on the noise-attenuated central seismic gather.