Automatic fluid coding and hydraulic zone determination

Patent metadata

Field	Value
Publication number	US-10444402-B2
Application number	US-201313901844-A
Country	US
Kind code	B2
Filing date	May 24, 2013
Priority date	May 25, 2012
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

Systems, methods, and media for processing formation pressure test data are provided. The method includes determining using a processor, a plurality of regressions for measurements of the formation pressure test data, and determining that two or more of the plurality of regressions represent a fluid code. The method also includes combining the two or more of the plurality of regressions representing the fluid code to generate a first fluid-type regression, and combining two or more other ones of the plurality of regressions representing a second fluid code to generate a second fluid-type regression. The method further includes determining that the first fluid-type regression and the second fluid-type regression are in a first hydraulic zone, and calculating a location of a boundary between the first fluid-type regression and the second fluid-type regression by extrapolating the first and second fluid-type regressions to a point of intersection therebetween.

First claim

What is claimed is:

1. A method for processing formation pressure test data, comprising:
obtaining a plurality of rules that define whether two or more fluids in a reservoir are in a single hydraulic zone based at least in part on density, pressure, or a combination thereof;
obtaining measurements taken during a formation pressure test;
determining, using a processor, a plurality of regressions based on the measurements;
determining that two or more of the plurality of regressions represent a fluid code;
combining the two or more of the plurality of regressions representing the fluid code to generate a first fluid-type regression;
combining two or more other ones of the plurality of regressions representing a second fluid code to generate a second fluid-type regression;
determining that the first fluid-type regression and the second fluid-type regression are both in a first hydraulic zone by evaluating the first fluid-type regression and the second fluid-type regression against the plurality of rules;
calculating a location of a boundary between the first fluid-type regression and the second fluid-type regression by extrapolating the first and second fluid-type regressions to a point of intersection therebetween;
displaying a result showing the first fluid-type regression, the second fluid-type regression, the boundary between the first and second fluid-type regressions, and the first hydraulic zone, based on the measurements and the application of the plurality of rules; and
creating a development plan for the formation based at least in part on the calculated location of the boundary.

2. The method of claim 1 , further comprising determining that a third fluid-type regression, adjacent to the second fluid-type regression, is not in the first hydraulic zone.

3. The method of claim 1 , wherein determining the plurality of regressions comprises:
determining a plurality of sliding regressions, such that each of the measurements is included in at least two of the plurality of sliding regressions; and
selecting a plurality of best-fit regressions from the plurality of sliding regressions, such that each of the measurements is included in at most one of the best-fit regressions, wherein the plurality of regressions comprises the plurality of best-fit regressions.

4. The method of claim 3 , further comprising:
calculating a quality score for each of the measurements; and
adjusting the plurality of sliding regressions based on the quality score for each of the measurements of each of the plurality of sliding regressions.

5. The method of claim 4 , further comprising:
calculating fit errors for the plurality of sliding regressions;
comparing the fit errors to a mean error of the fit errors for the plurality of sliding regressions; and
filtering one or more of the measurements based on comparing the error to the mean error, a proximity of the one or more measurements to one or more other measurements having a higher quality score, or both.

6. The method of claim 3 , wherein the plurality of sliding regressions are three-point regressions.

7. The method of claim 1 , wherein determining that two or more of the plurality of regressions represent the fluid code comprises determining that slopes of the two or more of the plurality of regressions are within a threshold amount of difference from one another.

8. The method of claim 1 , wherein determining that the first fluid-type regression and the second fluid-type regression are in the first hydraulic zone comprises:
determining that the first fluid-type regression is representative of a lower pressure gradient than a pressure gradient represented by the second fluid-type regression;
determining that a deepest measurement of the first fluid-type regression is shallower than a shallowest measurement of the second fluid-type regression; and
determining that an extension of the first fluid-type regression and an extension of the second fluid-type regression intersect between the deepest measurement of the first fluid-type regression and the shallowest measurement of the second fluid-type regression.

9. The method of claim 1 , further comprising calculating an uncertainty in the location of the boundary.

10. The method of claim 1 , further comprising matching hydraulic zones determined at a first wellbore with hydraulic zones determined at a second wellbore based at least partially on a depth of boundaries between the hydraulic zones for each of the first wellbore and the second wellbore.

11. The method of claim 1 , wherein the measurements are non-visual.

12. The method of claim 1 , wherein the plurality of rules comprises:
if a density of a superposed fluid code is within a predetermined threshold of a density of a subjacent fluid code, the fluid codes are in hydraulic communication, unless one or more of the following is true:
the density of the subjacent fluid code is lower than the density of the superposed fluid code;
a pressure of the superposed fluid code is higher than a pressure of the subjacent fluid code; or
an extrapolation of a subjacent fluid code and an extrapolation of a superposed fluid code is not at an intermediate point between a deepest measurement of the superposed fluid code and a shallowest measurement of the subjacent fluid code.

13. The method of claim 12 , wherein applying the plurality of rules to the first fluid-type regression and the second fluid-type regression to determine that the first fluid-type regression and the second fluid-type regression are in the first hydraulic zone comprises:
determining that the first fluid-type regression is superposed with respect to the second fluid-type regression;
determining a density of the first fluid-type regression and a density of the second fluid-type regression;
determining a pressure of the first fluid-type regression and a pressure of the second fluid-type regression;
extrapolating an intersection between the first fluid-type regression and the second fluid-type regression; and
applying the plurality of rules to the first and second fluid-type regressions, wherein the first fluid-type regression is the superposed fluid code and the second fluid-type regression is the subjacent fluid code.

14. The method of claim 1 , further comprising determining an amount, a composition, or both of a reservoir fluid based in part on the results that are displayed.

15. The method of claim 1 , further comprising developing a reservoir based on the reservoir development plan.

16. The method of claim 1 , further comprising monitoring a reservoir based in part on the results.

17. A processor system, comprising:
one or more processors; and
a memory system comprising one or more computer-readable media storing instructions that, when executed by at least one of the one or more processors, cause the processor system to perform operations, the operations comprising:
obtaining a plurality of rules that define whether two or more fluids in a reservoir are located in a single hydraulic zone based at least in part on density, pressure, or a combination thereof;
receiving formation pressure test data;
determining a plurality of regressions for measurements of the formation pressure test data;
determining that two or more of the plurality of regressions represent a fluid code;
combining the two or more of the plurality of regressions representing the fluid code to generate a first fluid-type regression;
combining two or more other ones of the plurality of regressions representing a second fluid code to generate a second fluid-type regression;
det

Assignees

• Schlumberger Technology Corp

Inventors

• Dubost Francois
• Guyomar Yannick
• Marché Olivier
• Ayan Cosan
• D'Halluin Florent
• Wlodarczyk Sylvain

Classifications

• E21B49/008 Primary

  by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor (measuring pressure E21B47/06) · CPC title

• G06F30/20

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• G06F17/18

  for evaluating statistical data {, e.g. average values, frequency distributions, probability functions, regression analysis (forecasting specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title

• G01V11/002 Primary

  Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant (means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B) · CPC title

• G01V9/00

  Prospecting or detecting by methods not provided for in groups G01V1/00 - G01V8/00 · CPC title