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Brunei District

COMPASS 2003.11 Quick Reference

(For Internal Use Only)

Brunei Well Planner Liew Yew Leong 1. 27-Sep-2004 2. 17-Dec-2004 3. 29-Dec-2004 4. 02-Jan-2005

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COMPASS (Computerized Planning and Analysis Survey System)

Tables of contents Part I – COMPASS Fundamentals (For Directional Driller Quick Reference) 1. To refresh 3 2. To Open Survey Editor or Plan Editor 3 3. To open different levels of data properties 3 4. To set North Reference to Grid North 5 5. To create new survey 6 6. To set Definitive Survey (Final Survey) 10 7. To set Survey Tool-Error 11 8. To set Vertical Section 12 9. To set Casing Program 12 10. To create Sidetrack Well 13 11. To import Survey 13 12. To export Survey 13 13. Survey Report Listing 14 14. Survey Report Listing with UTM or BRSO 16 15. To run Anti-Collision Report 17 16. To run simple Section/Plan View Plots 19 17. To run 3D Plot 21 Part II – COMPASS Introduction 1. COMPASS 2003.11 Log on 22 2. Commend log in error 22 3. COMPASS Well Explorer 23 - 25 4. Database Set-Up

A). COMPASS Database Hierarchical Level 26 B). Set-up/create Custom Measurement Systems (Done once only) 27 - 28 C). Update BGGM Magnetic Model 29 I). Create New Company 29 - 32 II). Create Survey Tool-Error Models for New Company 33 - 35 III). Create New Project (Field) 36 IV). Create Site (Structure) 37 V). Create Well 38 - 40 VI). Create Well bore 40-41 VI). Create Actual Design 41 - 44

5. Survey Import A. Import survey data from UT or TXT file 45 - 49 B. Import survey data from excel file. 50 - 52 C. Import Export survey data from Survey to Survey. 53 - 56

6. COMPASS Well Explorer Copy and Paste Function 56 - 57 7. COMPASS Well Explorer Drag and Drop Function 57-58 8. How do I do the bulk edit on MD/INC/Az in COMPASS Survey Editor? 59 - 61 9. How do I create Sidetrack well in COMPASS? 62 - 66 10. How do I change the RKB elevation in the COMPASS Survey Editor or Plan Editor?

Case 1. Original Hole only 66 - 70 Case 2. Original Hole + Sidetracks 70 - 73

11. How do I create Well Plan in COMPASS? A). Curve-Hold-Curve example 74 - 79 B). Curve-Hold-Curve-Hold and Curve-Hold-Curve-Curve example 80 - 82

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Part I - COMPASS Fundamentals (For Directional Driller Quick Reference) 1. To refresh Press F5 2. To Open Survey Editor or Plan Editor Highlight and double click on the survey or proposal. Example: Open Survey Editor 1. Click on Actual Design 2. Highlight and double click on survey section Open Gyro Survey Section Example: Open Plan Editor

1. Click on Actual Design

2. Highlight and double click on here

Highlight and double click on here

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Open Plan Editor Prop14 28-12-2004 3. To open different levels of data properties Highlight the level and click on right-hand mouse button Example: To open ‘Actual Design’ properties

Click on here

1. Highlight ‘Actual Design’ and click on right-hand mouse button

2. Select and click on properties

All Survey data are under ‘Actual Design’. A ‘Actual Design’ may have many surveys (raw + Sucop + IFR correction) but only one ‘Definitive Survey’ (Final Survey).

Total Surveys

Definitive Survey (Final Survey)

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Example: To open Well Properties 1. Highlight Well level and click on right-hand mouse button 2. Select and click on Properties Highlight and open Site Level Properties Important Note: System default is True North In COMPASS system will add in the Grid Convergence onto Azimuth when user switches to True/Grid North

4. To set North Reference to Grid North

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5. To create new survey Create -> 1. New Wellbore 2. New Actual Design 3. New Survey 1. Create New Wellbore Highlight Well level and click on right-hand mouse button. Select ‘New Wellbore…’

Common Name: Original Hole, Sidetrack-1, Sidetrack-2……Legal Name: EG14, EG14S1, EG14S2………… (Well Name)

Basic Settings

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2. Create New Actual Design System will auto prompt out the pop-up window Or create from Wellbore level Highlight Wellbore level and click on right-hand mouse button 3. Create New Original Hole Survey System will auto prompt out the pop-up window

Name: Definitive Survey

Set Vertical Section

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Or create from ‘Actual Design’ level Highlight ‘Actual Design’ and click on right-hand mouse button System will auto open the Survey Editor To open Survey Editor, refer to page 3 Now key in Gyro Survey Data

Input Survey NameSet Tool-Error

2. To Open Survey Editor or Plan Editor

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Continue build-in MWD survey ` Now key in MWD Survey Data

Tie on Gyro last survey station @ 244m MD

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Open ‘Auctual Design” Properties Click on ‘Survey Program’ Example: RS-19 ST4

6. To set Definitive Survey (Final Survey)

Set Final Section Surveys in here

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Open Survey Properties Example: EG-14 Or Open Survey Editor then click on Survey Properties

7. To set Survey Tool-Error

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Open “Actual Design’ Properties Select ‘Vert Section’ Example: EG-14 Or open Survey Editor then select ‘Actual Design’ Properties 1. Double click on Casing Icon 2. Or open Survey Editor then click on Casing Icon. 1. 2.

8. To set Vertical Section

9. To set Casing Program

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Refer to Page 62 to 66. Refer to Page 45 to 56. 1. Open Survey Editor 2. Go to File -> Export -> Survey Data. 3. Select Export to ‘File’ 4. Select Pre-Define Format Example: EG-14

10. To create Sidetrack Well

11. To import Survey

12. To export Survey

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1. List out Section Survey – Open Section Survey Editor 2. List out complete Survey from surface– Open ‘Actual Wellpath’ Example: EG-14 1. To list Section Survey – MWD 244-1175m O/H A). Open MWD 244-1175m O/H Survey Editor B). Select Report -> Survey… C). Select COMPASS Standard Report

13. Survey Report Listing

Please note that Range selected from Surface Report still listing from tie onPoint 244.00MD

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D). Report Listing From Tie on Point 2. To list Complete Survey (From Surface) – MWD 244-1175m O/H A). Open EG14 Actual Wellpath (Highlight and double click on Definitive Survey) B). Select Report -> Survey… C). Select COMPASS Standard Report

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D). Report Listing From Surface A). Open Survey Editor or Actual Wellpath Select ‘_Borneo RSO’ from Local pull-down list B). Select COMPASS Standard Report

14. Survey Report Listing with UTM or BRSO Coordinates

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C). Report Listing With UTM or BRSO Coordinates 1. Go to ‘Analysis’ select ‘Anticollision Settings 2. Go to ‘Analysis’ select ‘Select Offset Designs’ 1. Anticollision Settings A). Scan every 10m B). Filter out SF=15 i.e. don’t show on Anti-collision report listing if SF > 15 2. Select Offset Designs

15. To run Anti-Collision Report

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Offset Design Selection 3. Now Anticollision function on Go to Report -> Anticollision Select COMPASS Anticollision

Reference WellShown on bold

Object Wells (√)

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Summary Listing Detail Listing

16. To run simple Section/Plan View Plots

Click on here

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To show Proposal vs Survey on quick plot Select current survey on ‘Offset Design Selection’

Survey

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To rotate the 3D graph To zoom in/zoom out the 3D graph Press and hold left-hand mouse button Press and hold right-hand mouse button Mouse pointer will change to Mouse pointer will change to then move the mouse then move the mouse

17. To run 3D Plot

Click on here

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Part II – COMPASS Introduction 1. COMPASS 2003.11 Log on Standalone Computer (Local) Data Source: EDM 2003.11 Single User Db - Created by MSDE (Microsoft Desktop Engine) on default User: edm Password: landmark Build 38 = Patch 1 (148MB) 10-June-2004 Build 41 = Patch 2 (318MB) 17-August-2004 Build 48 = Patch 3 (628MB) 10-November-2004 EDM – Engineer’s Data Model 2. Commend log in error 1. Make sure your bitlock is plugged on the parallel port. 2. Check your license.dat file. It should locate on c:\Landmark\LAM directory. 3. Re-run flexid.exe program from c:\Landmark\LAM\bin to detect your bitlock and the license.dat file. Any problem please e mail to Asia Pacific International Technical Support Email: apsupport@lgc.com

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3. COMPASS Well Explorer

Definitive Survey (Final Survey)

No of Surveys under ‘Actual Design’

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Local = DQ Horizontal OriginThree reference points: Slot, Site (Structure), Other Site (Structure)

DrillQuest Horizontal Origin/Vertical OriginFour reference points

Current selected data

Datum = DQ Vertical Origin Show TVD Sub Sea

(System) - System defaultDrill Floor - User defined User can also add in and specify some more reference points i.e. Structure Elevation, DFE (West Pelaut) and so on.

System Units : API, API – US Survey Feet and SI (System Provides)User can create and define local System Unit.

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Current selected data Shown on bold Current selected data

Shown on highlight

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4. Database Set-Up A). COMPASS Database Hierarchical Level 1. Database 2. Company (Operator) 3. Project (Field) 4. Site (Structure) 5. Well 6. Well bore 7. Plan (Well Proposal) Design (Actual Survey) To show the Well Name in slot running order, key in slot No then well name in Well Properties (Common Well Name). To show Well Name in ascending order, just key in well name without slot No. COMPASS database set-up Sequences: Create Company -> Copy/Create Tool-Error Models -> Project -> Site -> Well -> Wellbore -> Plan (Well Proposal) -> Design (Actual Survey) DrillQuest Database Hierarchical: Folder -> Project -> Structure -> Well -> Proposal/Survey (No Wellbore Level) Data Hierarchical Level

Main Settings

1. Company Level Anti-collision Policies – Scan Method + Warning Type Survey Error Model (Cone of Error, ISCWSA,

Systematic) 2. Project (Field) Level System Datum (MSL, Ground Level, LAT) Default Magnetic Model (BGGM) Grid System (Geographic Reference System) 3. Site Level Structure Elevation Azimuth Reference (True or Grid North) 4. Well Level Well Units (API, API-US, SI) Depth Reference (RKB, Drill Floor, System Datum…) 5. Wellbore Level Wellbore Type Parent Wellbore Magnetic Model Actual Design Well Elevation (Depth Reference Information) Definite Survey (Survey Program) Vertical Section Survey Survey Tool-Error (Good magnetic, poor magnetic…) Tie on (From Wellhead, Survey, User defined) Plan Design Well Elevation (Depth Reference Information) Tie on (From Wellhead, Survey, User defined) Survey Tool Program Vertical Section

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B). Set-up/Create Custom Measurement Systems (Done once only) a) From COMPASS Tools->Units… (COMPASS only)

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b) Or from EDM Administration (COMPASS + Well Plan + Others)

Click on here

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C). Update BGGM Magnetic Model Directly copy the BGGM or IGBGCF files from c:\drilling\dq3\CoordSys to c:\Landmark\COMPASS\Config\Geomagnetic Models I). Create New Company (Operator)

1. Go to File -> New -> Company… 2. Or Highlight database level and click on the right-hand mouse button. Select New Company… Use the same method to create new Project (Field), Site (Structure), Well, Well bore and Plan/Design.

Click on here

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1. General 2. Anti-collision Scan Method Options There are three options for ‘Survey Error Model’. 1. Cone of Error 2. ISCWSA – Industry Steering Committee for Wellbore Survey Accuracy. 3. Systematic Ellipse (Wolff and de Wardt) Sigma – This value states the confidence level for the survey errors in number of standard deviations. 1 Sigma implies that roughly 65% of reading will be within the state error. 2 Sigma implies that 95% of readings will be within the stated error.

Brunei Shell Settings User defined and will display on Anti-collision Report.

5 Information Tabs

Brunei Shell Select - Systematic Ellipse (Wolff & de Wardt)

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Warning Type Options Brunei Shell Select – Error Ratio 3. Calc Defaults Select Minimum Curvature Select All Projects

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4. Wellbore Types

User defined and will use as filter in Anti-collision and Well Plot Programs.

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II). Create Survey Tool-Error Models for New Company Each time when you create a new Company, the system will assign an empty set of ‘Survey Tools’ for the new Company. You can copy the survey tool-error models from other Company or key in the survey tool-error models. Click on here 1. To create the new survey tool-error models. Click on ‘New’. Select ‘Tool Type’ and enter the Error Coefficients. 2. To copy the existing tool-error models. Open and export Other Company ‘Survey Tools’ then re-open the new Company ‘Survey Tools’. Click on ‘Import’

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Brunei Shell Tool-Error Settings – Systematic (Wolff and De Wardt)

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III). Create New Project (Field) 1. General System provides three options 1. Ground Level 2. LAT 3. MSL User can add in and specify new reference point i.e. Brunei Chart Datum. 2. Map Info Select the correct Geodetic System And System will calculate the correct Geographic Latitude & Longitude Brunei Sell Geodetic System - BRSO

Shown on Report Listingand on Screen

Get from c:\Landmark\COMPASS\Config\Geomagnetic Models

3 Information Tabs

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IV). Create Site (Structure)

Structure Elevation

Get from Project Properties General Tab

Important Note: System default is ‘True’ North Remember to set it to ‘Grid’ North

Key in Structure center or any one of the Structure Slot Coordinates

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V). Create Well 1. General Tab Example CPDP-10 Structure Select View -> Well Name -> Common Name Sort in Slot Number

User can use this option to show the Well name sort in Slot or Well name in ascending order on the screen.

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Example CPDP-10 Structure Select View -> Well Name -> Legal Name 2. Depth Reference

Shown on Report Listing User can keep multi-datum records.

Gray cell read only. Use by Actual/Plan Design and user can’t edit/delete the record.

White cells editable Free and user can delete the record

Sort in Well Name

Lock or use by Actual/Plan Design

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3. Location 4. Audit Information VI). Create Wellbore

Enter Well (Slot) Coordinates

Use this option to show the Wellbore name in Common or Legal name on the screen.

Get from Company Properties - Wellbore Types Tab

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VII). Create Actual Design

Default Model Name set on Project Properties General Tab

Use in Traveling Cylinder and Ladder Plots

Get from Well Properties DepthReference Tab

Survey DFE

System Default

User defined

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Example ‘Make Definitive from Survey Tie-ons’ RS-18 ST1 Definite Survey After created (key-in) or imported the survey, user need to double check your ‘Survey Program’ – Active Surveys. To mark the definite survey move the mouse pointer to RS-18 ST1 Definite Survey and click on the right-hand mouse button to get the ‘Actual Design Properties’ pop-up window and go to Survey Program Tab.

Click here to pick the definite surveys. In COMPASS only one survey tool can be assigned to one individual survey. If you have Gyro and MWD surveys then you need to create two surveys. Not as in DQ user can create one survey and assigned multiple tool errors to it.

Select Definite Survey (Final Survey)

In this case there is no active survey. Survey Program is empty.

Survey created

Click on here and select the surveys

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After select the survey click on here

System will pick up and show the upper section survey from ST tie on

Re-click on here

System grays up the cells. Protected and read only i.e. user can’t delete the records.

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Example RS-9 ST2 Before click on ‘Make Definitive from Survey Tie-ons’ After Click on ‘Make Definitive from Survey Tie-ons’

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5. Survey Import A). Import survey data from UT or TXT file Open Survey Editor, go to File -> Import -> Survey Data… Step 1 - Locate the survey text or UT file and click on ‘Open’.

Clipboard function is not on i.e. no survey data copy to Clipboard.

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Step 2 Click on ‘Next’ after select the correct ‘Original data type’. Step 3

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Step 4 Step 5

Set the correct Survey Type

Survey Imported. Click on ‘Save’

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Step 6 Step 7

To set Survey Tool-Error Click on Survey Properties Go to General Tab.

To enter Survey Comments Click on ‘Survey Annotations’

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Step 8 Step 9

To set Survey Vertical Section Click on Actual Design Properties

Select User Defined and key in the AzimuthTo set Casing Depths Click on here

Click on here and add in the new Casing Name, if you can’t find the Casing Name in System Build-in.

System Build-in Casing Name

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B). Import survey data from Excel File. Step 1 Open Survey Excel File Highlight and copy all the data. Step 2

Open Survey Editor Now the ‘Clipboard’ function is on Click on ‘Open’

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Step 3 Step 4

Select correct ‘Delimiters’ Click on ‘Next’

Select correct ‘Original data type’ and click on ‘Next’

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Step 5 Step 6 Click on ‘OK’ Survey data Imported Step 7 Set Survey Tool-Error/Comments/Vertical Section/Casing Depths

Select correct ‘Type’ Click on ‘Finish’

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C). Export Import survey data from Survey to Survey. Example: Export EGDP-1/Slot 04/EG-14 NSG 0-244m O/H survey data to Site #1/Wellbore #1 Example-1 1. Open NSG 0-244M O/H Survey Editor. Go to File -> Export -> Survey Data. 2. Select Export to ‘Clipboard’. Click on ‘OK’

Export NSG 0-244m O/H data to Example-1

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3. Now open Example-1 Survey Editor 4. Select File -> Import -> Survey Data… Clipboard function should on Select Import From ‘Clipboard’ Filter out Line 1 to 5

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Job Done 6. COMPASS Well Explorer Copy and Paste Function Step 1 Highlight Survey #2 Click on the right-hand mouse button Select Copy… Step 2 Highlight Well #1 Definite Survey Click on the right-hand mouse button Select ‘Paste…’

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Click on ‘Yes’ Job Done Now just re-name the new created survey record. 7. COMPASS Well Explorer Drag and Drop Function In COMPASS user can use Well Explorer drag and drop function to copy the data (Company, Project, Site, Well, Well bore, and Design) from one location and paste it into another location. Example Drag and drop test project level to Company level

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Click on ‘Yes’

Job doneNow we have test project under Company

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8. How do I do the bulk edit on MD/INC/Az in COMPASS Survey Editor? In DQ it is very easy to correct the wrong applied Magnetic Azimuth by using ‘Adjust Azimuth’ function. 1. Highlight all the data then click on the ‘Adjust Azimuths’ icon. 2. Input the +-‘Azimuth Adjustment’ figure In COMPASS Step 1 Step 2

Open Survey Editor

Export Survey data to Clipboard

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Export Survey data to Clipboard Step 3 Import Survey data from Clipboard Clipboard function is on Click on ‘Open’

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At Import Wizard Step 3Enter the Azimuth Adjustment -0.5

Step 4

Job done

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9. How do I create Sidetrack well in COMPASS? Before we create the Sidetrack well let us look at the following set-up methods. The answer is simple. Just look at your left-hand side Well Track diagram. Liew, The first method is correct. Every individual sidetrack and/or lateral should be represented by a separate wellbore. There can only be one definitive survey for each wellbore, so you would not be able to show two separate paths under a single wellbore. Regards, Stuart Sargeant

A. This wayCreate Sidetrack under new Wellbore

B. Or this wayCreate Sidetrack under Original Hole Wellbore

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Example: SERIA Field S-28 Wrong Sidetrack set-up in COMPASS You should not see two or more separate paths under a single wellbore. After correction Correct Sidetrack Set-up in COMPASS

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Example Step 1 Create New Wellbore Highlight Well #2 and click on the right-hand mouse button Select ‘New Wellbore…’ Step 2 Create New Survey Highlight Wellbore Sidetrack-1 Click on the right-hand mouse button Select ‘New Survey…’

Tie in Original Hole

Select latest BGGM Model

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Select Original Hole Survey section

Empty Survey created. To open Survey Editor double click on here.

Survey DFE

Tie in Point

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Step 3 Survey Editor open Enter Survey data or Import the Survey data To set Tool-Error - Click on Survey Properties icon To set Survey Comment – Click on Annotations icon To mark Active Survey (Survey Program) and set Vertical Section – Click on Actual Design Properties icon To set Casing Depths – Click on Casing icon 10. How do I change the RKB elevation in the COMPASS Survey Editor or Plan Editor?

Case 1 – Original Hole onlyOriginal DFE is 25.91m Need to change to NDFE 28.91m

Step 1 Click on right-hand mouse buttonOpen Well Properties

Original

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Step 2 Key in the new Datum

Gray cell (Read only)User can’t edit the figure

Can’t use the same datum name – Drill Floor

Build in new DFE

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Step 3Open Actual Design Properties On General Tab select the new DFE

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Job done Double click here for checking Check the TVDss and Coordinates

Now

After

Before

Select TVD Sub

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Cell turns to white User can delete the old DFE recordJust highlight the record and press ‘Delete’ key.

Two old records were deletedIt is recommended to keep the old DFE for tracking

Case 2 – Original Hole + Sidetracks Drag & Drop FA42 for example

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Original Hole Sidetrack-1 & Sidetrack-2 Original DFE is 25.10m Now need to change Sidetrack-2 DFE to 30.10m Step 2 Add in New DFE Click on ‘OK’

Step 1Click on the right-hand mouse buttonOpen Well Properties

Step 3 Click on right-hand mouse button Open Actual Design Properties

Select new DFE

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Click on ‘Yes’

Job done

Re-open Well Properties

In this case (Gray Cells)25.10 used by Original Hole & ST1 30.10 used by Sidetrack-2 Now question: Do I need to adjust Original hole & Sidetrack-1 to the same DFE in COMPASS?

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Let us look for the answer 1. Information from Stuart Sargeant Liew, The datum logic is one thing I really have problems with in Compass. Theoretically, you only need to select the default datum at the well level and everything under that well should reflect that selection whenever you open something under that well. However, you also need to select the proper datum from the Datum list on the tool bar at the top of the Compass screen and make sure it stays at the proper selection when you switch between wellbores. You also need to check the box that reads TVDs to System if you always want the vertical depths relative to MSL. For some reason the datum keeps changing when you switch between wellbores under a single well and I can’t understand the logic. It has been explained to me and Landmark assures me that the logic is working correctly but I still have trouble understanding it. I guess the short answer is that whenever you open a wellbore or proposal or survey, you should make sure the datum is set correctly in the list at the tope of the screen. Regards, Stuart Sargeant 25-Oct-2004

Original Hole MD’s auto adjusted based on new DFE setting

Original Hole MD’s unchanged based on original DFE setting

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2. From Landmark’s business advertisement The main different of Depth Reference Datum between DrillQuest and COMPASS software is as follows: In DQ the Depth Reference Datum is created and specified on ‘Well Properties’.i.e. once you have changed the DFE on Well Properties then all the Surveys/Proposals under this Well will auto change to the new DFE as well. In COMPASS the Depth Reference Datum is created at the Well Properties ‘General Tab’ but is specified in the Actual/Plan Design Properties ‘General Tab’. 11. How do I create Well Plan in COMPASS? Step 1

Example Egret EG16 Proposal

Click on the right-hand mouse buttonClick on ‘New Plan…’

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Key in Proposal name Select DFE Select default for Original hole proposal In the Well Planning Design it is almost 90% using CHC, CHCH and CHCC Planning Modules. So we only focus on these Planning Modules.

System auto open Plan Editor

2D Well Planning 3D Well Planning CHC/CHCH/CHCC

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A). Curve-Hold-Curve Example To build in the following same well proposal in COMPASS Step 2 Click on here and build in the targets

TVD Sub Sea not on i.e. TVD from Drill Floor

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Same format as in DQ

Planning Methods is on after key in the KOP point. Select Optimum Align and C-H-C

Step 3 After build in the targets Exit and go to Plan Editor

Click on here to calculate

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‘Align on Target’ function Move the cursor on raw 5 and select C-H-C function again.

Use this function (Align on Target) if user wants to hit Target-1 & Target-2 on tangent

In DQ the same function is here

Answer

Same answer

Now the ‘Project Back’ function is on.

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Get the following calculation after click on ‘Calculate’. Last step is to select ‘Curve’ to Target-4. Move the cursor on row 9 and click on here ‘Tread Targets’ Thread function on Highlight Target-4 Click on here Click on ‘OK’ Job done

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B). Curve-Hold-Curve-Hold and Curve-Hold-Curve-Curve examples Highlight the above Plan Editor from row 3 to row 9. Press ‘Delete’ key. Step 1 Select ‘Optimum Align’ Curve-Hold-Curve

After click on ‘Calculate’‘Project Back’ function onNow click on here

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Step 2 Open Project Back function

For Curve-Hold-Curve-Hold Set Build rate = 0 and CL = Hold length

For Curve-Hold-Curve-HoldSet Build rate > 0 and User has CL/TVD/Inc/Surface options to select.

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Curve-Hold-Curve-Curve

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Appendix 1. More Sigma information from Stuart Sargeant Hi Liew, Sigma values can not be applied to Wolfe & DeWardt Error models. All error values in Wolfe & DeWardt models including any possible sigma values are defined in the parameters themselves so it would be dangerous to apply additional sigma values to these models. The base models, e.g. Good Gyro, Good Magnetic, Poor Gyro etc. have been determined as having the approximate equivalent of a 2 sigma value included in the parameters. Because the application of sigma values is a recent process associated with the ISCWSA models whose sigma value is 1 sigma, it would be very dangerous apply sigma values to customized Wolfe & DeWardt models. In the Wolfe & DeWardt SPE paper they specifically state that sigma values are not relevant to their models. If you really want to show the sigma values for Wolfe & DeWardt models in DrillQuest, then the best way to do this is to convert the Wolfe & DeWardt models to ISCWSA models. You can do this quite simply in DrillQuest by opening the Survey Tool Properties for the Wolfe & DeWardt tool and then clicking on the Save as ISCWSA File button. This will prompt you for a file name and save the Wolfe & DeWardt values as the equivalent of 1 sigma values. You can then create a new ISCWSA tool and associate it with the file you saved from the Wolfe & DeWardt values. Regards, Stuart Sargeant 31-May-2004

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Stuart,

Thanks for the information. But why in AnaDrill drilling software Drilling Office 3.0 their ISCWSA sigma is 2.7955 (95% Confidence)? Please refer to the attached file. When they had developed their SLB ISCWSA, they just asked me to send the Brunei Shell Wolfe & DeWardt to their software group. So when I had received the new version Drilling Office 3.0, they already converted the Wolfe & DeWardt model to SLB ISCWSA model. If we use the ISCWSA model in our DQ software then it means that we have less confidence in Ellipse dimension probability. Sigma 1 = 68.27% and Sigma 2 = 95.45% Regards, Liew Hi Liew, I’m not sure. There are a couple of things to consider. Although we state that 2 Sigma = 95.45% Confidence, this is in a single dimension but we need to consider three dimension so you have to cube root the confidence level. Therefore 95.45% becomes 95.45 x 95.45 x 95.45 = 86.96% confidence that a survey station is located within the volume of its associated ellipse. BP use (or used to use) 2.58 sigma indicating a 99% confidence level, but in actual fact the three dimensional confidence level is 97.03%. Here are a couple of useful links… http://mathworld.wolfram.com/StandardDeviation.html http://mathworld.wolfram.com/NormalDistribution.html http://people.hofstra.edu/faculty/Stefan_Waner/RealWorld/normaltable.html You can use the table in the third link to calculate the confidence level from a sigma value. Example: Anadrill specify a sigma value of 2.7955. From the table, this represents a normal distribution of 0.4974. Double it and multiply by 100 to get a 99.58% confidence level. If you cube this value, you get 98.45%. In their report, Anadrill specify a 3-D 95.00% confidence limit. The cube root of 0.9500 is 0.983048 which presumably is the 1-D confidence level, but this equates to a 2.39 sigma value. In other words, I don’t know where Anadrill get 95% from a 2.7955 sigma value. If you look at the 2 sigma value, the table shows normal distribution as 0.4772 and 0.4772 x 2 x 100 = 95.44%, which is what DrillQuest uses although this is specified as a single dimension confidence level. (There is some debate whether the single dimensional or three dimensional confidence levels should be reported in uncertainty reports). Regards, Stuart Sargeant 02-June-2004

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2. COMPASS Well Explorer Drag and Drop Rules All drag and drop operations copy the data; data is never cut or moved.

1. You cannot drag and drop an Actual Design. However, if you copy a Wellbore, any Actual Designs under that Wellbore are copied. This is also true for copying done at the Well, Site, Project and Company level.

2. You cannot drag a Wellpath from the Associated Data Viewer into an Actual Design. 3. If you drag a Planned or Prototype Design to different Project, targets will not be copied with the

Design. As a result, the plan will no longer have any targets associated with it. 4. Depending where a Design sidetrack Wellbore is dropped, Plan and Survey tie-on information may be

lost and as a result survey program may be missing information. 5. If a Survey is dropped into a Wellbore or Actual Design in another Company, the Survey will lose its tool

information. (In COMPASS only). 6. You can not drag and drop Catalogs. Instead you must use the right-click menu Copy and Paste

functions. 3. COMPASS database – MSDE or Oracle? Stuart,

Since we can select Oracle or MSDE database in Compass software, any comment which database is better for Brunei area?

Regards,

Liew Liew, The general rule of thumb seems to be that if there will ever be more than five people accessing the database at the same time, use something other than MSDE. However, instead of using Oracle, you might consider using SQL. This is similar to MSDE but you are not limited to five concurrent users. I believe it is easier to manage than Oracle. Regards, Stuart Sargeant 05-Oct-2004

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4. Ellipses on Well Path center or Off-set Well Path center? In COMPASS the default of Systematic Survey Tool Type is ellipse on Well Path center i.e. no Survey Bias. User has the option to turn on the ‘Survey Bias’ function in COMPASS Systematic Survey Tool Type setting.

Systematic Ellipse Error Surface

ISCWSA Error Surface Displaying ‘Bias’

Calculated Trajectory

‘ Most Likely’ Trajectory

Survey Bias

Survey Station

Systematic Ellipse Error Surface

ISCWSA Error Surface Displaying ‘Bias’

Calculated Trajectory Calculated Trajectory

‘ Most Likely’ Trajectory

Survey Bias

Survey Station

Ellipse offset center if Bias on

87

5. COMPASS Tips