Quantitative Estimation of Reservoir Dynamic Properties
1. Does 4D Seismic data really complement well production information that remains spatially sparse and temporally dense by essentially offering information on the variations of reservoir properties across the entire reservoir @ a given production time as a function of the varying seismic amplitudes?
2. If the changes in each of the reservoir properties has an independent impact on the seismic data, then, how precisely, the superposition of all the effects caused by the simultaneous variations in any particular dynamic reservoir property could be captured in the absence of quantitatively estimating the simultaneous contribution of each reservoir property to the final observed data (4D AVO)?
About (1): You pretty much answered your question in the way you posed it. Some complementary information and insights you can derive from 4D seismic are for example:
- Location of compartment boundaries. You can invert the distance of a reservoir boundary to a degree from well-tests. If you see the signal from a reservoir boundary in the pressure response of a well-test, you will still not know in which direction the boundary is.
- In turbidite reservoirs, you can see the architecture of reservoir channels from 4D seismic, which is complementary to the information gained from well-tests.
I am sure you can imagine other complementary uses of 4D seismic and well-test information.
About (2): You are asking a typical interpretation question, where you can have several explanation of root causes which cam, in principle, explain your observed data. You ask to do the interpretation "in the absence of quantitatively estimating the simultaneous contribution of each reservoir property to the final observed data". I would advocate to do exactly that ... estimate the magnitude of changes in observed 4D AVO attributes (4D intercept+gradient, Changes in Acoustic Impedance + Vp/Vs ratio, ... ) from properties of interest (Change in reservoir pressure, partial fluid saturations, temperature changes, ...), then use this insight in the interpretation of the observed 4D changes.
Lastly, you can also use reservoir simulation models in combination with 4D seismic. This opens a whole new set of questions on how to best do this, and is a discussion for another time.
Best regards,
Jorg
- Badges
- Science topic
- Similar topics
- Biological Science
- Physiology
- Physiological Processes
- Stress