Velocity stack processing of seismic data

Claim 3

A method of velocity stacking as set forth in claim 1 which is further characterized by the step of: performing velocity constraints on each common depth point trace group such that only those events having selected duration and velocities within a preselected range of velocities are subject to the step of determining velocities.

Claim 4

A method of velocity stacking as set forth in claim 1 wherein said step of determining comprises: selecting events which occur on a predetermined number of adjacent ones of said common depth point trace groups; further dividing said common depth point trace groups into a plurality of successive time-displaced trace groups; and comparing each of said selected seismic events which occur within approximately equal times for each trace group to establish velocities for all of said seismic events of each common depth point trace group.

Claim 5

A method of velocity stacking as set forth in claim 3 wherein said step of selecting comprises the steps of: removing residual Delta t from respective traces of each common depth point trace group; and compositing each of said step-out removed traces such that said common depth point trace group is represented in vertical seismic signal travel time.

Claim 6

A method of velocity stacking as set forth in claim 1 which is further characterized to include the steps of: plotting each event relative to travel time as an impulse marking on one of a plurality of parallel lines, each parallel line representing the travel time scale for each common depth point trace group; and overlaying said plotted impulse indications with a graph of eVent velocities versus travel time, said overlaid travel time scale coinciding with said first plotted travel time scale.

Claim 7

A method of velocity stacking as set forth in claim 3 which is further characterized to include the steps of: plotting each event relative to travel time as an impulse marking on one of a plurality of parallel lines, each parallel line representing the travel time scale for each common depth point trace group; and overlaying said plotted impulse indications with a graph of event velocities versus travel time, said overlaid travel time scale coinciding with said first plotted travel time scale.

Claim 8

A method of velocity stacking as set forth in claim 4 which is further characterized to include the steps of: plotting each event relative to travel time as an impulse marking on one of a plurality of parallel lines, each parallel line representing the travel time scale for each common depth point trace group; and overlaying said plotted impulse indications with a graph of event velocities versus travel time, said overlaid travel time scale coinciding with said first plotted travel time scale.

Claim 9

A method of velocity stacking as set forth in claim 1 which is further characterized to include the step of: determining a time-velocity function with all primary event indications present in the multi-trace seismic information, and limiting the step of determining velocity for seismic events occurring on each common depth point trace group to those velocities which approximately coincide with the determined time-velocity function.

Claim 12

A method of stacking multi-trace seismic data as set forth in claim 9 which includes the further steps of: constraining event indications of the common depth point data trace groups such that only those event indications present on a predetermined number of adjacent data traces are acceptable for further processing in the step of summing said event indications, and limiting said further processing to said acceptable event indications.

Claim 13

A method of stacking multi-trace seismic data as set forth in claim 10 which is further characterized to include the step of: placing further amplitude constraint upon said data trace group event indications whereby only event indication exceeding predetermined amplitude threshhold are applied to the step of summing said event indications.

Claim 14

A method of stacking multi-trace seismic data as set forth in claim 9 which is further characterized to include the steps of: plotting each of said multiple basement point events relative to travel time as an impulse marking on one of a plurality of parallel lines, each parallel line representing the travel time scale for each common depth point trace group; and overlaying said plotted impulse indications with a graph of multiple basement point event velocities versus travel time, said overlaid travel time scale coinciding with said first plotted travel time scale.

Claim 15

A method of stacking multi-trace seismic data as set forth in claim 9 which is further characterized to include the step of: determining a time-velocity function for all primary event indications present in the multiple basement point event indications, and limiting the step of determining event indications for each common depth point data trace grOup for those velocities which approximately coincide with the data determined time-velocity function.

Claim 16

A method of stacking multi-trace seismic data as set forth in claim 13 which is further characterized to include the steps of: providing an output display wherein all events are indicated in terms of time versus velocity of the event.

Claim 17

A method of multi-trace seismic data as set forth in claim 14 which is further characterized to include the step of: constraining event indications of the common depth point data trace groups such that only those event indications present on a predetermined number of adjacent data traces are acceptable for further processing in the step of summing said event indications, and limiting said further processing to said acceptable event indications.

Claim 18

In a method of velocity stacking multi-trace seismic information utilizing an automatic data processing system, a program to perform an operation wherein selected seismic trace indications are continuously summed to derive only primary event information, comprising the steps of: dividing said multi-trace seismic information into plural trace groups of plural sequentially related channels, each trace group representing seismic trace information sequals as derived for a common depth point; analyzing said information signals to determine velocities for seismic events occurring at greater than a selected amplitude on each channel of each common depth point trace group; and summing all event velocity determinations of each common depth point trace group relative to trace time to provide a multiple depth point output of selected event velocities versus time.

Claim 19

In a method of velocity stacking multi-trace seismic information utilizing an automatic data processing system, a program to perform an operation wherein selected seismic trace indications are continuously summed to derive only primary event information, comprising the steps of: dividing said multi-trace seismic information into plural trace groups of plural sequentially related channels, each trace group representing seismic trace information sequals as derived for a common depth point; analyzing said information signals to determine velocities for seismic events occurring at greater than a selected amplitude on each channel of each common depth point trace group; and summing all event velocity determinations of each common depth point trace group relative to trace time to provide a multiple depth point output of selected event velocities versus time.

Claim 20

A method of velocity stacking as set forth in claim 16 which is further characterized by the step of: performing velocity constraints on each common depth point trace group such that only those events having selected duration and velocities within a preselected range of velocities are subject to the step of determining velocities.

Claim 21

A method of velocity stacking as set forth in claim 16 wherein said step of determining comprises: selecting events which occur on a predetermined number of adjacent ones of said common depth point trace groups; further dividing said common depth point trace groups into a plurality of successive time-displaced trace groups; and comparing each of said selected seismic events which occur within approximately equal times for each trace group to establish velocities for all of said seismic events of each common depth point trace group.

Claim 22

A method of velocity stacking as set forth in claim 18 wherein said step of selecting comprises the steps of: removing residual Delta t from respective traces of each common depth point trace group; and compositing each of said step-out removed traces such that said common depth point trace group is represented in vertical seismic signal travel time.

Claim 23

A method of velocity stacking as set forth in claim 16 which is further characterized to include steps of: plotting each event relative to travel time as an impulse marking on one of a plurality of parallel lines, each parallel line representing the travel time scale for each common depth point trace group; and overlaying said plotted impulse indications with a graph of event velocities versus travel time, said overlaid travel time scale coinciding with said first plotted travel time scale.