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DATUM_NAMEDATUM_TYPEORIGIN_DESCRIPTIONREALIZATION_EPOCHREMARKSINFORMATION_SOURCE
Ordnance Datum NewlynverticalOrdnance Survey of Great Britain
Malin HeadverticalMean sea level between January 1960 and December 1969.1970Ordnance Survey of Ireland
Belfast LoughverticalMean sea level between 1951 and 1956 at Clarendon Dock, Belfast.1957Malin Head (datum code 5130) used for 1:50,000 and smaller mapping.Ordnance Survey of Northern Ireland
Ordnance Datum Newlyn (Orkney Isles)verticalConnected to Newlyn datum by triangulation from the British mainland.Ordnance Survey of Great Britain
Fair IsleverticalOrdnance Survey of Great Britain
LerwickverticalOrdnance Survey of Great Britain
FoulaverticalOrdnance Survey of Great Britain
Sule SkerryverticalOrdnance Survey of Great Britain
North RonaverticalOrdnance Survey of Great Britain
StornowayverticalOrdnance Survey of Great Britain
St. KildaverticalOrdnance Survey of Great Britain
Flannan IslesverticalOrdnance Survey of Great Britain
St. MarysverticalOrdnance Survey of Great Britain
DouglasverticalOrdnance Survey of Great Britain
PoolbegverticalLow water mark of the spring tide on the 8 April 1837 at Poolbeg Lighthouse, Dublin.1837Superseded by Belfast Lough and Malin Head (datum codes 5130-31).'The Irish Grid - A Description of the Co-ordinate Reference System' published by Ordnance Survey of Ireland, Dublin and Ordnance Survey of Northern Ireland, Belfast.
Puerto RicogeodeticFundamental point: Cardona Island Lighthouse. Latitude:17 deg 57 min 31.40 sec N; Longitude: 66 deg 38 min 07.53 sec W (of Greenwich).1901NADCON conversion program provides transformation from Puerto Rico Datum to NAD83 (original 1986 realization) but making the transformation appear to user as if from NAD27.Ordnance Survey of Great Britain and http://www.ngs.noaa.gov/ (NADCON readme file).
Naparima 1955geodeticFundamental point: Naparima. Latitude: 10 deg 16 min 44.860 sec N; Longitude: 61 deg 27 min 34.620 sec W (of Greenwich).1955Naparima 1972 is an extension of the Naparima 1955 network of Trinidad to include Tobago.Ordnance Survey International.
AccrageodeticFundamental point: GCS Station 547. Latitude: 5 deg 23 min 43.3 sec N; Longitude: 0 deg 11 min 52.3 sec W (of Greenwich).Superseded in 1978 by Leigon datum (code 6250).Ordnance Survey International
IRENET95geodeticETRS89 stations in Ireland1995Densification of ETRS89Ordnance Survey of Ireland
Sierra Leone Colony 1924geodeticFundamental point: Kortright. Latitude: 8 deg 28 min 44.4 sec N; Longitude: 13 deg 13 min 03.81 sec W (of Greenwich).1924Ordnance Survey International.
Sierra Leone 1968geodeticFundamental point: SLX2 Astro. Latitude: 8 deg 27 min 17.567 sec N; Longitude: 12 deg 49 min 40.186 sec W (of Greenwich).1968Extension and readjustment with additional observations of 1960 network. Coordinates of 1960 stations change by less than 3 metres.Ordnance Survey International.
OSNI 1952geodeticPosition fixed to the coordinates from the 19th century Principle Triangulation of station Divis. Scale and orientation controlled by position of Principle Triangulation stations Knocklayd and Trostan.1952Superseded by Geodetic Datum of 1965 alias 1975 Mapping Adjustment or TM75 (datum code 6300).Ordnance Survey of Northern Ireland.
Barbados 1938geodeticFundamental point: HMS Challenger astro station M1; latitude 13 deg 04 min 32.53 sec N; longitude 59 deg 36 min 29.34 sec W (of Greenwich).1938Ordnance Survey of Great Britain.
LeigongeodeticFundamental point: GCS Station 121, Leigon. Latitude: 5 deg 38 min 52.27 sec N; Longitude: 0 deg 11 min 46.08 sec W (of Greenwich).Superseded Accra datum (code 6168) from 1978. Coordinates at Leigon fundamental point defined as Accra datum values for that point.Ordnance Survey International
Naparima 1972geodeticFundamental point: Naparima. Latitude: 10 deg 16 min 44.860 sec N; Longitude: 61 deg 27 min 34.620 sec W (of Greenwich).1972Naparima 1972 is an extension of the Naparima 1955 network of Trinidad to include Tobago.Ordnance Survey International.
OSGB 1936geodeticFundamental point: Pre 2002: Herstmonceux, Latitude: 50 deg 51 min 55.271 sec N; Longitude: 0 deg 20 min 45.882 sec E (of Greenwich). From April 2002 the datum is defined through the application of the OSTN02 transformation (tfm code 1039) to ETRS89.1936Ordnance Survey of Great Britain
TM65geodeticAdjusted to best mean fit 12 stations of the OSNI 1952 primary adjustment.1965Differences between OSNI 1952 and TM65 at these stations are RMS 0.25m east, 0.23m north, maximum vector 0.57m. TM65 superseded by and not to be confused with Geodetic Datum of 1965 alias 1975 Mapping Adjustment or TM75 (datum code 6300).'The Irish Grid - A Description of the Co-ordinate Reference System' published by Ordnance Survey of Ireland, Dublin and Ordnance Survey of Northern Ireland, Belfast.
Geodetic Datum of 1965geodeticAdjusted to best mean fit 9 stations of the OSNI 1952 primary adjustment in Northern Ireland plus the 1965 values of 3 stations in the Republic of Ireland.1975Differences from the 1965 adjustment (datum code 6299) are: average difference in Eastings 0.092m; average difference in Northings 0.108m; maximum vector difference 0.548m.'The Irish Grid - A Description of the Co-ordinate Reference System' published by Ordnance Survey of Ireland, Dublin and Ordnance Survey of Northern Ireland, Belfast.
Anguilla 1957geodeticFundamental point: station A4.1957Ordnance Survey of Great Britain.
Antigua 1943geodeticFundamental point: station A14.1943Ordnance Survey of Great Britain.
Dominica 1945geodeticFundamental point: station M12.1945Ordnance Survey of Great Britain.
Grenada 1953geodeticFundamental point: station GS8.1953Ordnance Survey of Great Britain.
Montserrat 1958geodeticFundamental point: station M36.1958Ordnance Survey of Great Britain.
St. Kitts 1955geodeticFundamental point: station K12.1955Ordnance Survey of Great Britain.
St. Lucia 1955geodeticFundamental point: station DCS3.1955Ordnance Survey of Great Britain.
St. Vincent 1945geodeticFundamental point: station V1.1945Ordnance Survey of Great Britain.

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