1. Oil or Gas???
Should there be a difference in seismic response (AVO) between an oil-filled reservoir and a gas-filled reservoir?
Model response with different rock & fluid properties
If there should be a difference, which fluid type does the seismic data support?
Extract amplitudes from near- and far-angle stacks
From our basin modeling & HC systems analysis, which fluid type should we expect
What did the source generate
What did the trap leak or spill
Quantitative
Slide 19
We may be able to do some quantitative analysis if the rock and fluid properties are such that we
expect a different seismic response for shale, water-filled sand, oil sand and gas sand
We can also do some qualitative analyses – modeling the basin’s history and the elements of the
HC system, e.g., what type of source rocks, when did they start to generate oil and gas, what
volumes of oil/gas were generated within the prospect’s drainage area, do we spill oil/gas into
the prospect’s drainage area, etc.
Recall my fear of gas flushing oil out of Block 5 back in Exercise 3?
Qualitative
Courtesy of ExxonMobil
L14 – Prospect Analysis