Method for deriving 3D output volumes using summation along flat spot dip vectors

Computer instructions on a computer readable media, comprising instructions to cause a processor to determine the existence of and location of hydrocarbon and water fluid contacts by analyzing spatial changes in 3D seismic data comprising the steps of:

• a) obtaining seismic attribute data as a 3D data volume;
• b) obtaining 3D dip and azimuth data as at least one set of 3D volume data and deriving corresponding 3D reliability volumes or deriving 3D censor volumes which are representative of portions of the at least one set of 3D volume data within which 3D dip data and azimuth data can be reliably determined;
• c) selecting a focused subvolume of interest within the at least one set of 3D volume data 3D data volume;
• d) determining reliability locations within the focused subvolume of interest having non-null 3D dip data and non-null 3D azimuth data within the 3D reliability volumes or 3D censor volumes across the focused subvolume of interest forming a sequence of reliability locations;
• e) computing an average for a plurality of vector dips around each reliability location in the sequence of the reliability locations forming at least one structural dip vector for each reliability location;
• f) determining a flat spot direction vector for each structural dip vector at each reliability location;
• g) defining sequences of distances from each reliability location to locations for interpolating seismic attribute data;
• h) for each sequence in the sequence of distances, interpolating seismic attribute data onto at least one flat spot direction vector for each reliability location forming sequences of interpolated seismic attribute data values;
• i) summing the sequences of interpolated seismic attribute data values forming summed sequences;
• j) storing the summed sequences of interpolated seismic attribute data values for each reliability location with null values for all non-reliability locations within the focused subvolume of interest, forming a 3D output subvolume;
• and
• k) the method is then repeated for all 3D volume data forming a 3D output volume.