 Bright Spots
1. Do you observe reflections from the top and the base of the reservoir?
2. Does the amplitude of these events vary in unison, dimming at the limit of the anomaly?
3. Do you observe constructive interference on the top reservoir event, where the side lobe of the flat spot, interferes with the trough of the top reservoir?
4. Do you observe destructive interference on the base reservoir event (water leg), where the side lobe of the flat spot interferes with the peak of the base reservoir?
5. Does the flat spot show brightening and dipping up towards the top reservoir?
6. Are the top and base reservoir amplitudes higher than the flat spot amplitude, they should always be so?
7. Is the flats pot the opposite polarity to top reservoir?
8. Is the amplitude anomaly consistent with structure in depth?
9. Is the a/b (anomaly/background) ratio consistent with modelling or your basin experience?
10. Are your observations consistent with the phase and polarity assumptions?
11. Have you considered non hydrocarbon explanations for the bright spot, i.e. changes in the encasing shale, volcanocalstics, coal, changes in overburden, low saturation gas, high porosity sands and tuning?
12. Do you observe an AVO anomaly and does it match your modelled response?
Note: if the hydrocarbon column is less than the thickness of the reservoir, you will not observe the base reservoir effects.
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