Method and apparatus for reservoir characterization using photoacoustic spectroscopy
A method and apparatus are provided that assess reservoir compartmentalization by determining whether there are compositional differences such as whether the isotopic ratios of carbon (13C/12C) or of oxygen (17O/18O) are the same or different in various parts of the reservoir. A quartz enhanced photoacoustic spectrometer is provided for analysis of reservoir samples taken in various parts of the reservoir for comparison of geochemical composition to estimate reservoir compartmentalization.
1. A method for estimating reservoir compartmentalization comprising:
analyzing a photoacoustic response from a first sample from a first location in the reservoir;
analyzing a photoacoustic response from a second sample from a second location in the reservoir; and
comparing the analysis of the first sample to the analysis of the second sample to estimate reservoir compartmentalization.
2. The method of claim 1 , wherein each photoacoustic response comprises a signal from a photoacoustic spectrometer.
3. The method of claim 1 , wherein each photoacoustic response comprises a signal from a quartz-enhanced photoacoustic spectrometer.
4. The method of claim 3 , wherein analyzing further comprises estimating an isotopic ratio.
5. The method of claim 1 , wherein analyzing further comprises estimating sample composition.
6. The method of claim 1 , wherein analyzing is performed downhole.
7. The method of claim 1 , wherein analyzing further comprises comparing phytane and pristine ratios.
8. The method of claim 1 , wherein analyzing further comprises estimating a distinguishing characteristic.
9. An apparatus for estimating reservoir compartmentalization comprising:
a photoacoustic spectrometer (PAS) configured to analyze a first sample from a first location in the reservoir and analyze a second sample from a second location in the reservoir; and
a processor configured to compare the analysis of the first sample to the analysis of the—second sample to estimate reservoir compartmentalization.
10. The apparatus of claim 9 , wherein the PAS further comprises a quartz-enhanced PAS.
11. The apparatus of claim 9 , wherein the processor is further configured to estimate compartmentalization using isotopic ratios for the samples.
12. The apparatus of claim 11 , wherein the isotopic ratios further comprise at least one of the set consisting of isotopic ratios of carbon ( 13 C/ 12 C) and isotopic ratios of oxygen ( 17 O/ 18 O).
13. The apparatus of claim 9 , wherein the processor is further configured to estimate sample composition.
14. The apparatus of claim 9 , wherein the analysis is performed downhole.
15. The apparatus of claim 9 , wherein the analysis further comprises comparing phytane and pristine ratios.
16. The apparatus of claim 9 , wherein the analysis further comprises a comparison of a distinguishing characteristic of the samples.
17. An apparatus for estimating reservoir compartmentalization, comprising:
a downhole tool configured to obtain samples from the reservoir;
a photoacoustic spectrometer (PAS) configured to analyze a first sample from a first location in the reservoir and analyze a second sample from a second location in the reservoir; and
a processor configured to compare the analysis of the first sample to the analysis of the second sample to estimate reservoir compartmentalization.
18. The apparatus of claim 17 , wherein the PAS further comprises a quartz enhanced PAS.
19. The apparatus of claim 17 , wherein the processor is further configured to estimate compartmentalization from a comparison of isotopic ratios from the first and second samples.
20. The apparatus of claim 17 , wherein the processor is further configured to compare a distinguishing characteristic of the first and second samples to estimate reservoir compartmentalization.