Abstract: The method and system of the present inventions provides a new approach for selecting frequencies comprising a minimal or limited frequency data set for imaging leading to an order of magnitude decrease in computation resources. Seismic data are acquired and transformed a frequency domain. The data may be gathered in any manner. A plurality of minimal frequency subsets are formed comprising selected frequencies. The frequencies may be selected so that more frequencies are selected for shallower image positions. The selected frequencies are imaged to form frequency images. The selected frequencies may be individually weighted to assure a full and balanced bandwidth. The frequency images are composited to form an intermediate or final composited migration image.

Abstract: The present invention provides a method and system for distributed residual tomographic velocity analysis using dense residual depth difference maps. Prestack seismic imaging is performed using an initial velocity field and interpreted horizons. A residual depth difference is estimated referenced to fixed offset and all horizons. Residual depth difference maps are computed for each offset and each horizon. The residual depth difference maps are back projected to determine slowness perturbation. The initial velocity model may be converted to slowness and the estimated slowness is composited therewith to produce a new slowness volume. The new slowness volume is converted to a new velocity volume for performing prestack seismic imaging. This process is repeated until the slowness perturbation is negligible or reaches a predetermined threshold.

Abstract: The method and system of the present inventions provides a new approach for selecting frequencies comprising a minimal or limited frequency data set for imaging leading to an order of magnitude decrease in computation resources. Seismic data are acquired and transformed a frequency domain. The data may be gathered in any manner. A plurality of minimal frequency subsets are formed comprising selected frequencies. The frequencies may be selected so that more frequencies are selected for shallower image positions. The selected frequencies are imaged to form frequency images. The selected frequencies may be individually weighted to assure a full and balanced bandwidth. The frequency images are composited to form an intermediate or final composited migration image.