Prediction of formation and stratigraphic layers while drilling

Patent metadata

Field	Value
Publication number	US-10732312-B2
Application number	US-201514717162-A
Country	US
Kind code	B2
Filing date	May 20, 2015
Priority date	May 20, 2015
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

An embodiment of a method of predicting a location of one or more features of an earth formation during a downhole operation includes acquiring reference data and identifying one or more reference data sections, each reference data section corresponding to a feature of interest and having an associated depth or depth interval, deploying a drilling assembly and drilling a target borehole in the earth formation, and performing measurements during the operation by a downhole measurement device to generate measurement data. The method also includes performing one or more correlations of the one or more measurement data sections with one or more reference data sections; and predicting at least one of a depth of a subsequent feature of interest located beyond a current carrier depth and a point in time of a future event associated with the subsequent feature of interest based on the correlation.

First claim

What is claimed is:

1. A method of predicting a location of one or more features of an earth formation during a downhole drilling operation, the method comprising:
acquiring reference data and identifying one or more reference data sections, each reference data section corresponding to a feature of interest and having an associated depth or depth interval, wherein the reference data includes measurements taken from a reference borehole;
deploying a drilling assembly and drilling a target borehole in the earth formation separate from the reference borehole, and obtaining measurements during the downhole drilling operation using a downhole measurement device to generate measurement data;
generating a depth shift function from correlation of one or more measurement data sections with the one or more reference data sections; and
predicting a location of a subsequent feature of interest ahead of the target borehole by applying the depth shift function;
continuously updating the depth shift function and the predicted location as additional measurement data are generated during the downhole drilling operation; and
at least one of automatically adjusting and changing operational parameters of the downhole drilling operation in response to the predicted location to react to the subsequent feature of interest.

2. The method of claim 1 , wherein the reference data includes seismic measurements of the earth formation.

3. The method of claim 1 , further comprising performing an action in response to predicting the location of the subsequent feature of interest, the action including at least one of: generating an alert, updating a plan for landing or steering the target borehole, updating or modifying a model of the earth formation, changing a rate of penetration of the drilling assembly, adjusting a drilling dynamics parameter, adjusting a drilling direction, adjusting one or more mud properties, changing, removing, or adding a downhole component, setting a casing, and adjusting the operational parameters.

4. The method of claim 1 , wherein the one or more reference data sections include at least one of: a data value change exceeding or falling below a selected threshold, and a distinctive pattern of data values associated with the feature of interest.

5. The method of claim 1 , wherein the correlation includes generating a data point for a depth shift as a function of depth or time.

6. The method of claim 1 , wherein the feature of interest includes at least one of: a change in lithology or facies of the earth formation, a surface of a stratigraphic layer, and a surface of a zone with relatively high pressure.

7. The method of claim 1 , wherein the correlation includes identifying the one or more reference data sections by calculating an absolute change in values of the reference data, calculating a relative change in the values, and correlating the absolute change or the relative change with the feature of interest.

8. The method of claim 7 , wherein the correlation includes monitoring the measurement data and the additional measurement data and selecting a depth interval in which an absolute change in values of the measurement data is within a selected range of the absolute change in values of the reference data, or in which a relative change in values of the measurement data is within a selected range of the relative change in the values of the reference data.

9. A system for predicting location of one or more features of an earth formation during a downhole drilling operation, comprising:
a carrier configured to be deployed in a borehole in the earth formation, the carrier including a drilling assembly configured to operate in a target borehole in the earth formation;
a downhole measurement device configured to perform measurements during the downhole drilling operation in the target borehole to generate measurement data; and
a processor configured to perform:
acquiring reference data and identifying one or more reference data sections, each reference data section corresponding to a feature of interest and having an associated depth or depth interval, wherein the reference data includes measurements taken from a reference borehole;
generating the measurement data by performing measurements during the downhole drilling operation using the downhole measurement device;
generating a depth shift function by correlation of one or more measurement data sections with the one or more reference data sections; and
predicting a location of a subsequent feature of interest ahead of the target borehole by applying the depth shift function;
continuously updating the depth shift function and the predicted location as additional measurement data are generated during the downhole drilling operation; and
at least one of automatically adjusting and changing operational parameters of the downhole drilling operation in response to the predicted location to react to the subsequent feature of interest.

10. The system of claim 9 , wherein the processor is configured to perform an action in response to the drilling assembly approaching the predicted location, the action including at least one of: generating an alert, updating a plan for landing or steering the target borehole, updating or modifying a model of the earth formation, changing a rate of penetration of the drilling assembly, adjusting a drilling dynamics parameter, adjusting a drilling direction, adjusting one or more mud properties, changing, removing, or adding a downhole component, setting a casing, and adjusting the operational parameters.

11. The system of claim 9 , wherein the one or more reference data sections include at least one of: a data value change exceeding or falling below a selected threshold, and a distinctive pattern of data values associated with the feature of interest.

12. The system of claim 9 , wherein the correlation includes generating a data point for a depth shift as a function of depth or time.

13. The system of claim 12 , wherein generating the data point for the depth shift includes constructing a curve, identifying a reference data section corresponding to the subsequent feature of interest, and calculating a depth in the target borehole of the subsequent feature of interest by applying a depth interval of the identified reference data section corresponding to the subsequent feature of interest to the curve.

14. The system of claim 9 , wherein the correlation includes identifying the one or more reference data sections by calculating an absolute change in values of the reference data, calculating a relative change in the values, and correlating the absolute change or the relative change with the feature of interest.

15. The system of claim 14 , wherein correlation of the one or more measurement data sections includes monitoring the measurement data and selecting a depth interval in which an absolute or relative change in values of the measurement data is within a selected range of the absolute or relative change the values of the reference data.

Assignees

• Bartetzko Anne
• Wessling Stefan
• Baker Hughes A Ge Co Llc

Inventors

• Bartetzko Anne
• Wessling Stefan

Classifications

• G01V1/50 Primary

  Analysing data · CPC title