Apache CanadaCoordinates Workshop

CBM inter-well distance calculation methods used by Apache and ERCBMap projections

Apache calculationLatitude and longitude of first point is A1 & B1Latitude and longitude of second point is A2 & B2The 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 * rIn navigation, this is a great circle distance between two points on the surface of a sphere

ERCB calculationGovt uses ATS ver 4.1 (MATS 2005) for lat/lon of the nearest section cornerMetes and bounds from section corner used to validate lat/lon of the surface locationDirectional/horizontal survey used to compute lat/long of the bottom holeLatitude 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 wellWells to be licensed more than 3 km from the control well are non-compliantERCB is using a 10TM map grid distance between the wells

An example of the differences

Sheet1

Apache 8-31-33-27-W4M to Hz 6-5-34-27-W4M

Great Circle DistanceNAD 83 UTM Coordinate Inverse

LatitudeLongitudeLat (rad)Long (rad)NorthingEasting

A151.888161B1-113.8004510.905619-1.986193A15752306.2B1307287.01866.8

A251.871112B2-113.8113540.905322-1.986383A25750439.4B2306463.7823.3

Distance (m)Distance (m)

2040.3832040.286

Apache 4-4-30-27-W4M to 16-11-30-27-W4M

Great Circle DistanceNAD 27 UTM Coordinate Inverse

LatitudeLongitudeLat (rad)Long (rad)NorthingEasting

51.536004-113.7508710.899473-1.9853275712793.0309282.9-2392.9

51.558969-113.6884850.899874-1.9842385715185.9313702.8-4419.9

Distance (m)Distance (m)

5018.5365026.081

Sheet2

Sheet3

The 10TM distanceText Text

Map Projections

Transverse Mercator Projectionsin Alberta

Metadata where would you be without it?Lat: 51.536004Lon: -113.750871

Metadata where would you be without it?North: 5712793.0East: 309282.9

UTM Zone 12

RecommendationsInverse between NAD83 UTM coordinates as shown on well site plan for well license applicationUse online tools as a check

Online ResourcesNatural Resources Canada Geodetic Toolshttp://www.geod.nrcan.gc.ca/tools-outils/index_e.phphttp://www.geod.nrcan.gc.ca/apps/indir/inverse_e.php

Movable Type Scripts Great Circle Distancehttp://www.movable-type.co.uk/scripts/latlong.html

United States Geodetic Survey Map Projections: A Working Manualhttp://pubs.er.usgs.gov/usgspubs/pp/pp1395

The Geographers Craft Map Projectionshttp://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html

Moving to NAD83: Impacts and Issues for Oil and Gas Companieshttp://www.cseg.ca/conventions/abstracts/2002/2002abstracts/Callaghan_S_Boudreault_D_Moving_To_NAD83_BUS-1.pdf

CAPP: Migrating from NAD27 to NAD83http://www.divestco.com/getdoc/0556a64e-f05f-4a61-a0c4-e6046d67b4a6/CAPP_Migrating-from-NAD27-to-NAD83.aspx

Questions?