Geophysical exploration using velocity picking from trial velocity function sorted time-coherency traces

Claim 3

The method of claim 1 wherein the displaying step comprises: selecting a subset of TVFs from the set of TVFs; and displaying for each TVF in the subset, a panel of time-coherency traces representing a plurality of CMPs.

Claim 4

The method of claim 1 wherein the displaying step comprises: selecting a subset of CMPs from the set of CMPs; and displaying for each TVF a panel of time-coherency traces representing the selected subset of

Claim 5

The method of claim 1 wherein the displaying step comprises: selecting a subset of TVFs from the set of TVFs; selecting a subset of CMPs from the set of CMPs; and displaying for each TVF in the subset a panel of time-coherency traces representing the selected subset of CMPs.

Claim 6

The method of claim 1 wherein the selecting step comprises: for each CMP of a selected set of CMPs summing a selected set of time-coherency traces and producing a set of stacked time-coherency traces; using the stacked time-coherency traces for generating a stacked section; and selecting points for generating a time-velocity function from TVF panels by selecting high coherency values in the TVF panels which occur at times corresponding to structural features in the stacked section.

Claim 7

The method of claim 2 wherein: the subset of TVFs comprises in the range of from 5 to 50 TVFs.

Claim 8

The method of claim 3 wherein: the subset of CMPs comprises at least 5 CMPs, optionally in the range of 5 to 50 CMPs along the seismic line of exploration.

Claim 9

The method of claim 4 wherein: the subset of TVFs comprises in the range of from 5 to 50 TVFs; and the subset of CMPs comprises in the range of 5 to 50 CMPs along the seismic line of exploration.

Claim 10

The method of claim 1 further comprising: generating a stacked seismic section having a time scale effective for user determination that time of occurrence of structural features is substantially the same as time of occurrence of high coherency events in TVF panels.

Claim 11

The method of claim 9 further comprising: generating a time velocity function based on points selected from TVF panels based on such determination.

Claim 14

The apparatus of claim 11 comprising: means for selecting a subset of TVFs from the set of TVFs; and means for displaying for each TVF in the subset, a panel of time-coherency traces representing plural CMPs.

Claim 15

The apparatus of claim 11 comprising: means for selecting a subset of CMPs from the set of CMP; and means for displaying for each TVF in the subset a panel of time-coherency traces for the selected subset of CMP.

Claim 16

The apparatus of claim 11 comprising: means for selecting a subset of TVFs from the set of TVFs; means for selecting a subset of CMPs from the set of CMPs; and means for displaying for each TVF in the subset a panel of time-coherency traces for the selected subset of CMPs.

Claim 17

The apparatus of claim 11 wherein the means for selecting comprises: means for generating a stacked section comprising stacked CMP gathers; and means for selecting points for generating a time, velocity function from TVF panels by choosing high coherency values in the TVF panels which occur at times corresponding to structural features in the stacked section.

Claim 18

Method for geophysical exploration comprising: conducting seismic exploration using CMP (common midpoint) exploration along a seismic line of exploration on earth's surface and generating a plurality of seismic traces and sorting the plurality of seismic traces into a plurality of CMP gathers; generating a plurality of TVFs (trial stacking velocity functions) for each CMP gather and evaluating coherency for each TVF and generating a time-coherency trace F(T,C) for each TVF for each CMP; generating a plurality of TVF panels with each panel comprising a plurality of coherency traces F(T,C) for a given TVF for a selected set of CMPs along the seismic line; displaying a selected set of TVF panels adjacent the stacked section; selecting (T,V) points by selecting T points on time-coherency traces in TVF panels, each T point having an associated V value determinable from the TVF; wherein the T point selection is based on at least one of coherency values in TVF panels and structural significance in the stacked section of CMP gathers; and generating a velocity function from the thus selected (T,V) points.

Claim 19

Method for geophysical exploration comprising: conducting seismic exploration using CMP (common midpoint) exploration along a seismic line of exploration on earth's surface and generating a plurality of seismic traces and sorting the plurality of seismic traces into a plurality of CMP gathers; generating a plurality of TVFs (trial stacking velocity functions) for each CMP gather and evaluating coherency for each TVF and generating a time-coherency trace F(T,C) for each TVF for each CMP; generating a plurality of TVF panels with each panel comprising a plurality of coherency traces F(T,C) for a given TVF for a selected set of CMPs along the seismic line; displaying a selected set of TVF panels adjacent the stacked section; selecting (T,V) points by selecting T points on time-coherency traces in TVF panels, each T point having an associated V value determinable from the TVF; wherein the T point selection is based on at least one of coherency values in TVF panels and structural significance in the stacked section of CMP gathers; and generating a velocity function from the thus selected (T,V) points.