1. Apache Canada Coordinates Workshop CBM inter-well distance calculation methods used by Apache and ERCB Map projections

2. Apache calculation Latitude and longitude of first point is A1 & B1 Latitude and longitude of second point is A2 & B2 The arc distance can be computed as: Arccos [cos(A1)cos(B1)cos(A2)cos(B2) + cos(A1)sin(B1)cos(A2)sin(B2) + sin(A1)sin(A2)]/360 * 2Pi * r In navigation, this is a great circle distance between two points on the surface of a sphere

3. ERCB calculation Gov’t uses ATS ver 4.1 (MATS 2005) for lat/lon of the nearest section corner ‘Metes and bounds’ from section corner used to validate lat/lon of the surface location Directional/horizontal survey used to compute lat/long of the bottom hole Latitude and longitude of the bottom hole are projected onto a 10TM map projection in their GIS A 3 km buffer circle is created around the control well Wells to be licensed more than 3 km from the control well are non-compliant ERCB is using a 10TM map grid distance between the wells

4. An example of the differences

5. The 10TM distance Text Text

6. Map Projections

7. Transverse Mercator Projections in Alberta

8. Metadata – where would you be without it? Lat: 51.536004° Lon: -113.750871°

9. Metadata – where would you be without it? North: 5712793.0 East: 309282.9 UTM Zone 12

10. Recommendations Inverse between NAD83 UTM coordinates as shown on well site plan for well license application Use online tools as a check

11. Online Resources Natural Resources Canada – Geodetic Tools http://www.geod.nrcan.gc.ca/tools-outils/index_e.php http://www.geod.nrcan.gc.ca/apps/indir/inverse_e.php Movable Type Scripts – Great Circle Distance http://www.movable-type.co.uk/scripts/latlong.html United States Geodetic Survey – “Map Projections: A Working Manual” http://pubs.er.usgs.gov/usgspubs/pp/pp1395 The Geographer’s Craft – Map Projections http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html Moving to NAD83: Impacts and Issues for Oil and Gas Companies… http://www.cseg.ca/conventions/abstracts/2002/2002abstracts/Callaghan_S_Boudreault_D_ Moving_To_NAD83_BUS-1.pdf http://www.cseg.ca/conventions/abstracts/2002/2002abstracts/Callaghan_S_Boudreault_D_ Moving_To_NAD83_BUS-1.pdf CAPP: Migrating from NAD27 to NAD83… http://www.divestco.com/getdoc/0556a64e-f05f-4a61-a0c4- e6046d67b4a6/CAPP_Migrating-from-NAD27-to-NAD83.aspx http://www.divestco.com/getdoc/0556a64e-f05f-4a61-a0c4- e6046d67b4a6/CAPP_Migrating-from-NAD27-to-NAD83.aspx

12. Questions?