Geometrical optimization of multi-well trajectories

• US 7,684,929 B2
• Filed: 11/03/2008
• Issued: 03/23/2010
• Est. Priority Date: 12/14/2004
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Acklestad, Darren Lee, Chapman, Clinton Dane, Prange, Michael David, Tilke, Peter Gerhard
• Primary Examiner(s): Nghiem; Michael P.
• Assistant Examiner(s): Le; Toan M
• Application Number:
  US12/263,668
• Publication Number:
  US 20090056935A1
• Time in Patent Office: 505 Days
• Field of Search: 702/9, 702/1, 702/2, 702/6, 702/11, 702/13, 702/14, 702/16, 703/5, 703/10, 166/245, 166/250.01, 367/14, 367/25, 367/73, 367/118
• US Class Current: 702/9
• CPC Class Codes: E21B 43/305 comprising at least one inclined or horizontal well
• CPC Class Codes: E21B 47/022 of the borehole, e.g. using geomagnetism
• CPC Class Codes: E21B 7/04 Directional drilling

Abstract

A novel method is presented to automatically design a multi-well development plan given a set of previously interpreted subsurface targets. This method identifies the optimal plan by minimizing the total cost as a function of existing and required new platforms, the number of wells, and the drilling cost of each of the wells. The cost of each well is a function of the well path and the overall complexity of the well.

Claims

1. A method for well path selection and optimization for subsurface drilling, comprising the steps of:

providing a computer program product, stored in a computer readable medium, comprising instructions to cause a computer to;

specify a plurality of well target locations, each well target location accessible by one or more well paths;

associate a well production value with each of said one or more well paths;

generate one or more well paths associated with said plurality of well target locations using said well production values and well path data, said one or more paths optimized for subsurface drilling.

2. The method of claim 1, further comprising the steps of:

revising said one or more well paths based on said well production value data and well path data; and

generating one or more final well paths, said final well paths optimized for subsurface drilling.

3. The method of claim 1, wherein said well production value includes Directional Difficulty Index (DDI) data.

4. The method of claim 3, wherein said Directional Difficult Index is given by:

5. The method of claim 3, wherein the step of generating one or more well paths associated with said plurality of well target locations further comprises the step of estimating drilling cost by a linear functional relationship:

Cost=Base×

[1+Modifier×

(DDI−

6.4)]

where Cost is a final computed drilling cost of one well incorporating DDI;

Base is a base computed drilling cost of one well based on rate of penetration and drilling parameters; and

Modifier is a multiplier to translate DDI to cost modifier.

6. The method of claim 5 wherein the Modifier value is set to 0.25.

7. The method of claim 1, wherein the step of generating one or more well paths associated with said plurality of well target locations further comprises the step of identifying the lowest cost optimized well paths.

8. A computer program product, stored in a computer readable medium, comprising instructions to cause a computer to:

specify a plurality of well target locations, each of said well targets accessible by a plurality of wells;

associate a well production value with each of said plurality of well target locations;

generate one or more well paths associated with said plurality of well target locations using said well production values and well path data, said one or more paths optimized for subsurface drilling.

9. The computer program product of claim 8, further comprising the steps of:

revising said one or more well paths based on said well production value data and well path data; and

generating one or more final well paths, said final well paths optimized for subsurface drilling.

10. The computer program product of claim 8, wherein said well production value includes Directional Difficulty Index (DDI) data.

11. The computer program product of claim 8, wherein the generating one or more well paths associated with said plurality of well target locations further comprises the step of identifying the lowest cost optimized well paths.