METHOD, SYSTEM AND APPARATUS FOR FORMATION TESTER DATA PROCESSING

• US 20090030614A1
• Filed: 07/25/2007
• Published: 01/29/2009
• Est. Priority Date: 07/25/2007
• Status: Active Grant

• Current Assignee: Andrew John Carnegie, Julian Pop, Kai Hsu
• Original Assignee: Andrew John Carnegie, Julian Pop, Kai Hsu
• Inventors: CARNEGIE, ANDREW JOHN, POP, JULIAN, HSU, KAI
• Granted Patent: US 7,680,600 B2
• Time in Patent Office: Days
• US Class Current: 702/6
• CPC Class Codes: G01V 1/48 Processing data

Abstract

A method for data processing includes transforming measurement data acquired in the time domain during an oilfield operation into a second domain to produce transformed data; identifying distortions in the transformed data; removing the distortions from the transformed data; and transforming back from the second domain to the time domain to produce cleaned-up data. The transforming measurement data may use a Fourier transform or a wavelet transform. The method may further include compressing the cleaned-up data or reconstructing signals from the cleaned-up data. A method for data processing includes decomposing measurement data, which are acquired in an oilfield operation, using a low pass filter to produce a first dataset; decomposing the measurement data using a high pass filter to produce a second dataset; removing distortions from the second dataset to yield a corrected second dataset; and reconstructing a corrected dataset from the first dataset and the corrected second dataset.

Claims

1. A method for processing formation tester data, comprising:

obtaining the formation tester data, wherein the formation tester data are time domain data acquired with a formation tester in a wellbore;

transforming the formation tester data into a second domain other than the time domain to produce transformed data;

identifying distortions in the transformed data;

removing the distortions from the transformed data to produce de-noised data; and

transforming the de-noised data from the second domain back to the time domain to produce cleaned-up formation tester data.

2. The method of claim 1, wherein the transforming the formation tester data comprises using a Fourier transform or a wavelet transform.

3. The method of claim 1, wherein the transforming the formation tester data uses a discrete wavelet transform.

4. The method of claim 3, wherein the identifying the distortions is by analyzing distribution of wavelet coefficients.

5. The method of claim 1, further comprising compressing the cleaned-up formation tester data.

6. The method of claim 5, wherein the compressing the cleaned-up formation tester data uses a wavelet transform.

7. The method of claim 1, further comprising deriving a formation property from the cleaned-up formation tester data.

8. A method for processing formation tester data, comprising:

obtaining the formation tester data, wherein the formation tester data are time domain data acquired with a formation tester in a wellbore;

decomposing the formation tester data using a low-pass filter to produce a first dataset;

decomposing the formation tester data using a high-pass filter to produce a second dataset;

removing distortions from the second dataset to yield a corrected second dataset; and

reconstructing a corrected formation tester data from the first dataset and the corrected second dataset.

9. The method of claim 8, wherein the low-pass filter and the high-pass filter are derived from Fourier transform or wavelet transform.

10. The method of claim 8, wherein low-pass filter and the high-pass filter are derived from discrete wavelet transform.

11. The method of claim 10, wherein the removing the distortions comprises analyzing a distribution of wavelet coefficients.

12. The method of claim 11, wherein the analyzing comprising analysis of at least one selected from the group consisting of a mean and a standard deviation of the distribution of wavelet coefficients as a function of a decomposition level.

13. The method of claim 8, further comprising compressing the corrected formation tester data to produce a compressed dataset.

14. The method of claim 13, wherein the compressing uses a wavelet lifting technique.

15. The method of claim 13, further comprising reconstructing signals from the compressed dataset.

16. The method of claim 15, further comprising identifying a trend or occurrence of an event from the reconstructed signals.

17. The method of claim 8, further comprising deriving a formation property from the corrected formation tester data.

18. A computer readable medium storing a program having instructions for:

transforming formation tester data, which are in time domain, into a second domain other than the time domain to produce transformed data;

identifying distortions in the transformed data;

removing the distortions from the transformed data to produce de-noised data; and

transforming the de-noised data from the second domain back to the time domain to produce cleaned-up formation tester data.

19. The computer readable medium of claim 18, wherein the transforming the formation tester data uses a Fourier or a wavelet transform.

20. The computer readable medium of claim 18, wherein the program further comprises instructions for deriving a formation property from the cleaned-up formation tester data.

21. A system for data processing, comprising a processor and a memory, wherein the memory stores a program having instructions for:

transforming formation tester data, which are in time domain, into a second domain other than the time domain to produce transformed data;

identifying distortions in the transformed data;

removing the distortions from the transformed data to produce de-noised data; and

transforming the de-noised data from the second domain back to the time domain to produce cleaned-up formation tester data.

22. The system of claim 21, wherein the program further comprises instructions for compressing the cleaned-up formation tester data.

23. The system of claim 21, wherein the transforming the formation tester data uses a Fourier transform or a wavelet transform.

24. The system of claim 21, wherein the system is disposed in a formation tester.