Why Projections Matter in an Active Horizontal Drilling Program Presented by Amber Robbins April 19, 2018 Houston PUG Workflow created at Castleton Resources, LLC

Overview Part 1 Part 2 Anecdote Directional survey ArcMap Workflow Examples

Petra Directional Survey Import

Petra

Petra

Petra

Directional Survey

ArcMap Project Projection needs to match Directional Survey Projection Projections 2 3 1 Source: https://gis.tulaliptribes-nsn.gov/Portals/8/images/spc_zones_04_lrg.jpg ArcMap Project Projection needs to match Directional Survey Projection

ArcMap Workflow 1 2 3

ArcMap Workflow 5 4 ~9,000’MD lateral Directional Survey 5 output Directional Survey displayed as points on a map

displayed as well path (polyline) ArcMap Workflow 6 6 output ~9,000’MD lateral N Directional Survey displayed as well path (polyline) on a map

ArcMap Workflow Possible Error Solution – export Point Event layer to shapefile Run Points to Line tool on the Point shapefile

Questions? Part 2 next… Examples Why Accuracy Matters…

True North vs. Grid North Differences 300ft. 300ft. Bottom Hole Location 300ft. Grid North Directional Survey (wrong projection) True North Directional Survey Surface Hole Location N Directional survey reference: Grid North--US State Plane Texas North Central NAD27 GeoGraphix map: US State Plane Louisiana North NAD27 Difference: ~300 feet.

Setback Rule Example 338.54 334.20 332.03 Setback Rules: Bottom Hole 338.54 Setback Rule Example 334.20 Horizontal Well Path 332.03 Setback Rules: 330’ from West Line 200’ from N/S Line 316.84 327.69 340.71 321.18 Surface Hole Hypothetical Lease 317.07

Why does precision matter when plotting horizontal wells on a map? Development program Spacing Drainage/Depletion Lease line/hard lines or setback rules Perforations and fracing $$$ Fines/Offsetting Mineral Owners

Thank You Castleton Resources, LLC Justin Robbins -GIS Analyst at Castleton Resources, LLC Mark Andreason -VP Geoscience at Castleton Resources, LLC

Recap Part 1 Part 2 Anecdote Directional surveys ArcMap Workflow Examples

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Houston GeoTechs group: https://www.linkedin.com/groups/8496213 Thank you! Questions? Amber Robbins Amber.Robbins.23@gmail.com https://www.linkedin.com/in/amber-l-robbins-738b3440/ Houston GeoTechs group: https://www.linkedin.com/groups/8496213

ArcMap Workflow ArcMap Ensure coordinate system of ArcMap project is the same as the directional survey Grid North coordinate system reference. If Directional Survey is referencing True North, correct the Azimuth, N/S E/W Offsets, and X, Y coordinates Calculate X,Y coordinates based on SHL and NS/EW offsets This step may be skipped if the survey includes coordinates Format Directional Survey to import into ArcMap (*.csv) X, Y or Lat/Long needed No spaces in headers No Nulls Add table to ArcMap ArcMap

ArcMap Workflow ArcMap Display XY Data as an Event X Field >>Easting Y Field>>Northing Set Coordinate System Ensure Data Frame Coordinate System is the same as the Directional Survey Coordinate System (Do not assume “conversion on the fly” will work) Points to Line Tool (in System Tools>>Data Management toolbox>>Features) Input Feature >Event Output Feature Class>Save new feature class Creates lines in sequence of survey May be able to import multiple surveys at once based on the line and sort options Check well position with survey location plat Surveyor may provide CAD *.dwg files to check well position Copy and Paste new well path into existing well paths shapefile/feature class Populate attribute table ArcMap

Directional Surveys Measured Depth Inclination: The deviation from vertical, irrespective of compass direction, expressed in degrees (angle). Azimuth: The compass direction (angle) of the wellbore as planned or measured by a directional survey typically measured clockwise from north onto a horizontal surface (map view) Directional Survey http://www.glossary.oilfield.slb.com/Terms

Directional Survey Source: http://os.is/gogn/unu-gtp-report/UNU-GTP-2013-27.pdf *Minimum Curvature Method is widely used to get NS and EW Offsets Use 3 decimal places in NS/EW Offsets for accuracy. (Example in Google Drive)

Grid Convergence Angle Real World Example Azimuth Directional Survey Source: https://gis.stackexchange.com/questions/61743/applying-proper-conversion-from-true-to-grid-bearing

Directional Survey Example

*Minimum Curvature Method is widely used to get NS and EW Offsets Use 3 decimal places in NS/EW Offsets for accuracy. Directional Survey http://www.drillingformulas.com/minimum-curvature-method/

Real World Example Directional Survey True North Azimuth = Grid Azimuth – (Grid Convergence) True North Azimuth = 103.10 – (-1.80) True North Azimuth = 103.10+1.80 True North Azimuth = 104.90 Azimuth relative to Grid North Grid North: Texas North Central 4202 Azimuth relative to True North Directional Survey *Directional Survey is for the same well but with different North references

Practice understanding Directional Surveys using this Minimum Curvature Method Excel Spreadsheet: http://www.drillingformulas.com/minimum-curvature-method/

Directional Survey Explanation https://www.safe.com/customers/devon-energy-well-directional-survey-processing/ https://www.safe.com/presentation/well-directional-survey-processing-in-fme/ FME software can handle batch directional survey conversions. FME is an acronym for Feature Manipulation Engine. FME is found at www.safe.com. FME is used to integrate data and automate workflows through multiple platforms. Directional Survey Oracle Hyperion is a similar integration-automation platform.

Bottom Hole Location Example Directional survey initially was imported “As is” into Petra. Grid North of the survey did not match the Project’s Grid North. Well #1 Well #2 Petra Non-corrected BHL 190 feet Corrected BHL N Petra example So, the directional survey was re-imported as True North. Petra rotated the survey by 3 degrees to align with the projection. 3 degrees changed the BHL by 190 feet

Petra Added Grid Convergence Subtracted Grid Convergence to Azimuth (1.58 degrees) Subtracted Grid Convergence from Azimuth (1.58 degrees) Petra *This path is more believable in a real world situation.

What do I do in Petra if… What do I do if the directional survey is not referencing the same projection as my project? Rotate Azimuth to True North by using the Grid Convergence Angle. Better yet, get the survey from the Directional Drilling Company rotated to True North. The directional survey (DS) referencing True North can be imported into your Petra project. The software will rotate the DS to the projection defined in the project. Petra

GeoGraphix Tip GeoGraphix Locator Map Imported using Prism Import Deviated Survey – not as accurate Imported using Spreadsheet Import – more accurate path As-Drilled Well While-Drilling Inset Map As-Drilled Well While-Drilling Well N ~1000 ft. Imported using Spreadsheet Import – more accurate path GeoGraphix Imported using Prism Import Deviated Survey – not as accurate N Use the Spreadsheet Import from WellBase to import Deviated Survey Data. More data can be imported (MD, INC, AZM, NS Offset, EW Offset, Survey Number). Plus the Coordinate System can be selected. I do not recommend using Prism Import Deviated Survey Data Import. As seen above, there are differences in the way imported data displays on the map.