Transcript Apache Canada Coordinates Workshop • CBM inter-well distance calculation methods used by Apache and ERCB • Map projections Apache calculation • • Latitude and longitude of first point.

Apache Canada
Coordinates Workshop
• CBM inter-well distance calculation
methods used by Apache and ERCB
• Map projections
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
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
An example of the differences
Apache 8-31-33-27-W4M to Hz 6-5-34-27-W4M
Great Circle Distance
Latitude
A1
A2
51.888161
51.871112
B1
B2
NAD 83 UTM Coordinate Inverse
Longitude
Lat (rad)
Long (rad)
-113.800451
-113.811354
0.905619
0.905322
-1.986193
-1.986383
Northing
A1
A2
5752306.2
5750439.4
Easting
B1
B2
307287.0
306463.7
Distance (m)
Distance (m)
2040.383
2040.286
Apache 4-4-30-27-W4M to 16-11-30-27-W4M
Great Circle Distance
NAD 27 UTM Coordinate Inverse
Latitude
Longitude
Lat (rad)
Long (rad)
Northing
Easting
51.536004
51.558969
-113.750871
-113.688485
0.899473
0.899874
-1.985327
-1.984238
5712793.0
5715185.9
309282.9
313702.8
Distance (m)
Distance (m)
5018.536
5026.081
The 10TM distance
• Text Text
Map Projections
Transverse Mercator Projections
in Alberta
Metadata – where would you be without it?
• Lat:
51.536004°
• Lon: -113.750871°
Metadata – where would you be without it?
• North:
5712793.0
• East:
309282.9
• UTM Zone 12
Recommendations
• Inverse between NAD83 UTM
coordinates as shown on well site
plan for well license application
• Use online tools as a check
Online Resources
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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
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Movable Type Scripts – Great Circle Distance
• http://www.movable-type.co.uk/scripts/latlong.html
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United States Geodetic Survey – “Map Projections: A Working Manual”
• http://pubs.er.usgs.gov/usgspubs/pp/pp1395
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The Geographer’s Craft – Map Projections
• http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html
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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
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CAPP: Migrating from NAD27 to NAD83…
• http://www.divestco.com/getdoc/0556a64e-f05f-4a61-a0c4e6046d67b4a6/CAPP_Migrating-from-NAD27-to-NAD83.aspx
Questions?