# US 2013/0155813 A1 · Iterative dip-steering median filter for seismic data processing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0155813 A1 - Document ID: US20130155813A1 - Status: Published application - Kind: A1 - Application number: 13/714,654 - Filed: 2012-12-14 - Published: 2013-06-20 - Earliest claimed: 2011-12-15 - Assignees: Saudi Arabian Oil Company - Inventors: Shoudong Huo; Weihong Zhu - Web page: https://patentgrep.com/patent/US20130155813A1 ## CPC - G01V 1/301: {for determining seismic cross-sections or geostructures} - G01V 1/364: {Seismic filtering (G01V1/37 takes precedence)} - G01V 2210/3248: Incoherent noise, e.g. white noise - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract An iterative dip-steering median filter is provided for random noise attenuation in seismic data where conflicting dips are indicated in the data. A number of dominant dips inside a processing window or sample of the data are identified by a Fourier-radial transform in the frequency-wavenumber domain. A median filter is then applied along the dominant dip to remove noise, and the remaining signal after filtering is retained for further median filter iterations. Iterations are repeated to apply the median filter along the most dominant dip in the remaining data. The processing continues in subsequent iterations until all selected dips have been processed. The remaining signal of each iteration is then summed for final output. ## Claims ### Claim 1 A computer implemented method of processing seismic data, in which time-spatial processing results of the data indicate conflicting dips, to attenuate random noise in the seismic data, comprising the computer implemented processing steps of: (a) assembling the time-spatial processing results of seismic data in the computer to form a series of overlapping time-spatial sample windows of the seismic data; (b) transforming the data of an individual one of the sample windows of seismic data into frequency-wavenumber domain data; (c) transforming the frequency-wavenumber domain data of the sample window data into Fourier-radial domain data; (d) determining a map of peak values of the Fourier-radial domain data of the sample window; (e) transforming selected ones of the peak values of the Fourier-radial domain data of the sample window to indicate dominant dips in the sample window data; (f) applying a median filter to the data in the sample window along a selected one of the indicated dominant dips to attenuate noise from the data in the sample window; and (g) storing the remaining signal in the median filtered data for the sample window. ### Claim 2 (depends on 1) The computer implemented method of claim 1, further including the steps of: determining whether each of the indicated dominant dips in the sample window data has been selected; and if not, selecting another indicated dominant dip and repeating steps (f) and (g) along the selected another indicated dominant dip; or if so, forming a sum of the stored remaining signal of the median filtered data output along the selected dominant dips. ### Claim 3 (depends on 1) The computer implemented method of claim 1, further including the steps of: determining whether each of the sample windows of the assembled seismic data have been selected; and if not, selecting an additional one of the sample windows of the assembled seismic data and returning to step (b) for performing steps (b) through (h) on the data of the additional one of the sample of the assembled seismic data; or if so, storing the assembled determined sum of the noise attenuated data output for each of the overlapping sample windows. ### Claim 4 (depends on 2) The computer implemented method of claim 2, further including the step of: displaying the stored assembled determined sum of the median filtered data output for each of the overlapping sample windows. ### Claim 5 (depends on 1) The computer implemented method of claim 1, wherein the seismic data being processed comprises a pre-stack gather. ### Claim 6 (depends on 1) The computer implemented method of claim 1, wherein the seismic data being processed comprises a post-stack section. ### Claim 7 (depends on 1) The computer implemented method of claim 1, wherein the step of determining a map of peak values of the Fourier-radial domain data comprises the step of: determining a sum for each of the radials in the Fourier-radial domain data. ### Claim 8 (depends on 7) The computer implemented method of claim 7, wherein the step of applying a median filter comprises the step of: applying a median filter to the dips in a descending sequence of dips. ### Claim 9 A data processing system for seismic data, in which time-spatial processing results of the data indicate conflicting dips, to attenuate random noise in the seismic data, the data processing system comprising: a data storage memory storing the time-spatial processing results of the seismic data; a processor for performing the steps of: (a) assembling the time-spatial processing results of seismic data in the computer to form a series of overlapping time-spatial sample windows of the seismic data; (b) transforming the data of an individual one of the sample windows of seismic data into frequency-wavenumber domain data; (c) transforming the frequency-wavenumber domain data of the sample window data into Fourier-radial domain data; (d) determining a map of peak values of the Fourier-radial domain data of the sample window; (e) transforming selected ones of the peak values of the Fourier-radial domain data of the sample window to indicate dominant dips in the sample window data; (f) applying a median filter to the data in the sample window along the indicated dominant dips to attenuate noise from the data in the sample window; and (g) storing the remaining signal of the median filtered data output for the sample window. ### Claim 10 (depends on 9) The data processing system of claim 9 wherein the processor further performs the steps of: determining whether each of the indicated dominant dips in the sample window data has been selected; and if not, selecting another indicated dominant dip and repeating steps (f) and (g) along the selected another indicated dominant dip; or if so, forming a sum of the stored remaining signal of the median filtered data output along the selected dominant dips. ### Claim 11 (depends on 9) The data processing system of claim 9, wherein the processor further performs the step of: determining whether each of the sample windows of the assembled seismic data have been selected; and if not, selecting an additional one of the sample windows of the assembled seismic data and returning to step (b) for performing steps (b) through (h) on the data of the additional one of the sample windows of the assembled seismic data; or if so, storing the assembled determined sum of the median filtered data output for each of the overlapping sample windows. ### Claim 12 (depends on 11) The data processing system of claim 11, further including: a display which forms an output record of the stored assembled determined sum of the median filtered data output for each of the overlapping sample windows. ### Claim 13 (depends on 11) The data processing system of claim 11, wherein the processor in performing the step of determining a map of peak values of the Fourier-radial domain data performs the step of: determining a sum for each of the radials in the Fourier-radial domain data. ### Claim 14 (depends on 10) The data processing system of claim 10, wherein the processor in performing the step of applying a median filter performs the step of: applying a median filter to the dips in a descending sequence of dips. ### Claim 15 A data storage device having stored in a computer readable medium computer operable instructions for causing a data processing system to process seismic data, in which time-spatial processing results of the data indicate conflicting dips, to attenuate random noise in the seismic data, the instructions stored in the data storage device causing the data processing system to perform the following steps: (a) assembling the time-spatial processing results of seismic data in the computer to form a series of overlapping time-spatial sample windows of the seismic data; (b) transforming the data of an individual one of the sample windows of seismic data into frequency-wavenumber domain data; (c) transforming the frequency-wavenumber domain data of the sample window data into Fourier-radial domain data; (d) determining a map of peak values of the Fourier-radial domain data of the sample window; (e) transforming selected ones of the peak values of the Fourier-radial domain data of the sample window to indicate dominant dips in the sample window data; (f) applying a median filter to the data in the sample window along the indicated dominant dips to attenuate noise from the data in the sample window; and (g) storing the remaining signal of the median filtered data output. ### Claim 16 (depends on 15) The data storage device of claim 15, wherein the instructions further include instructions causing the data processing system to perform the steps of: determining whether each of the indicated dominant dips in the sample window data has been selected; and if not, selecting another indicated dominant dip and repeating steps (f) and (g) along the selected another indicated dominant dip; or if so, forming a sum of the stored remaining signal of the median filtered data output along the selected dominant dips. ### Claim 17 (depends on 15) The data storage device of claim 15, wherein the instructions further include instructions causing the data processing system to perform the steps of: determining whether each of the sample windows of the assembled seismic data have been selected; and if not, selecting an additional one of the sample windows of the assembled seismic data and returning to step (b) for performing steps (b) through (h) on the data of the additional one of the sample windows of the assembled seismic data; or if so, storing the assembled determined sum of the median filtered data output for each of the overlapping time-spatial windows. ### Claim 18 (depends on 15) The data storage device of claim 15, wherein the instructions further include instructions causing the data processing system to perform the step of: displaying the stored assembled determined sum of the median filtered data output for each of the overlapping time-spatial windows. ### Claim 19 (depends on 15) The data storage device of claim 15, wherein the instructions further include instructions, in causing the data processing system to determine a map of peak values of the Fourier-radial domain data, to perform the step of: determining a sum for each of the radials in the Fourier-radial domain data. ### Claim 20 (depends on 15) The data storage device of claim 15, wherein the instructions further include instructions, in causing the data processing system to apply a median filter, to perform the step of: applying a median filter to the dips in a descending sequence of dips.