MEO WA360P – Merge
Test 0100 Survey Merge Analysis(Gross Amplitude)
Date 12/6/2014
Following the re-gridding of the Foxhound, Artemis3D and MEO3D surveys to a common grid (based on Artemis 3D Grid), three crosslines 3600, 4000 and 5000 were extracted from the supplied Radon Demultiple data. These were stacked, the amplitude was grossly corrected as follows: For Foxhound a factor of 0.0012 was applied to the data samples and a 2dB/sec gain was applied. For Artemis3D a scale factor of 0.43 was applied to the datasamples and a 5dB/sec gain was applied. The MEO data wasn’t changed.
Surveys and Test Crosslines
Foxhound
ArtemisMEO
Rosie
XL5000
XL4000
XL3600
Raw Stacks Crossline 3600
Foxhound Artemis Artemis MEO
Post Correction Stacks - Crossline 3600
Foxhound Artemis Artemis MEO
Raw Amplitude Decay - Crossline 3600
Foxhound Artemis MEOArtemis
Post Correction Amplitude Decay - Crossline 3600
Foxhound Artemis Artemis MEO
Raw Stacks Crossline 4000
Foxhound Artemis Artemis MEO
Post Correction Stacks - Crossline 4000
Foxhound Artemis Artemis MEO
Raw Amplitude Decay - Crossline 4000
Foxhound Artemis MEOArtemis
Post Correction Amplitude Decay - Crossline 4000
Foxhound Artemis MEOArtemis
Raw Stacks Crossline 5000
Foxhound Artemis Artemis MEO
Post Correction Stacks - Crossline 5000
Foxhound Artemis Artemis MEOFoxhound Artemis Artemis MEO
Raw Amplitude Decay - Crossline 4000
Foxhound Artemis MEOArtemis
Post Correction Amplitude Decay - Crossline 4000
Foxhound Artemis MEOArtemis
Conclusions:• The corrections applied to both Foxhound and Artemis appear to broadly bring the amplitudes into balance between the three
surveys. There is however some unknown amplitude treatment that has been applied to the Foxhound dataset. Furthermore lateral velocity variations are evident and matching at the survey boundaries cannot be achieved with a single/simple function. The gross correction that has been applied is sufficient to allow further analysis of the data
Recommendations:• It is likely that a different dataset will be supplied for the Foxhound survey, so this analysis will have to be revisited when that
dataset is available. • It has been suggested that to account for the lateral variations in amplitudes between the surveys a CDP based balance
calculated in a window surrounding the target zone be used. MEO has suggested that they supply the horizon grids to define the window.