Датумы


Датум - (топоцентрические системы координат) это привязка референц-эллипосида к  определеннной точке на земной поверхности.


Как известно, физическая поверхность Земли имеет сложную, с геометрической точки, зрения неправильную поверхность.

В геодезии она заменяется поверхностью геоида.

В картографии за математическу поверхность принимается близко соответствующий геоиду по форме и размерам эллипсоид вращения.

Топоцентрическая (региональная) система координат появляется следующим образом: некоторый эллипсоид располагается таким образом, чтобы для заданной территории среднеквадратичное отклонение поверхности эллипсоида от поверхности геоида было минимальным.

При этом отклонения на другой стороне Земли может быть на сколько угодно велико.


Следующая таблица описывает следующие параметры датума:


Номер - идентификатор датума в файле PROJECTIONS.PRJ

Датум - имя датума

Охватывает территории - территории, для которых датум используется

Эллипсиод - референц-эллипсоид для датума.


Номер

Датум

Охватывает территории

Эллипсоид

1

Adindan

Ethiopia, Mali, Senegal, Sudan

Clarke 1880

2

Afgooye

Somalia

Krassovsky

1007

AGD 66, 7 parameter

Australia, A.C.T.

Australian National

1008

AGD 66, 7 parameter

Australia, Tasmania

Australian National

1009

AGD 66, 7 parameter

Australia, Victoria/NSW

Australian National

1006

AGD 84, 7 parameter

Australia

Australian National

3

Ain el Abd 1970

Bahrain Island

International

118

American Samoa

American Samoa Islands

Clarke 1866

4

Anna 1 Astro 1965

Cocos Islands

Australian National

119

Antigua Island Astro 1943

Antigua, Leeward Islands

Clarke 1880

5

Arc 1950

Botswana, Lesotho, Malawi, Swaziland, Zaire, Zambia, Zimbabwe

Clarke 1880

6

Arc 1960

Kenya, Tanzania

Clarke 1880

7

Ascension Island 1958

Ascension Island

International

9

Astro B4 Sorol Atoll

Tern Island

International

8

Astro Beacon "E"

Iwo Jima Island

International

10

Astro DOS 71/4

St. Helena Island

International

11

Astronomic Station 1952

Marcus Island

International

12

Australian Geodetic 1966 (AGD 66)

Australia and Tasmania Island

Australian National

13

Australian Geodetic 1984 (AGD 84)

Australia and Tasmania Island

Australian National

120

Ayabelle Lighthouse

Djibouti

Clarke 1880

154

Beijing 1954

China

Krassovsky (#3)

1019

Belgian 1972 (7 parameters)

Belgium

International 1924

110

Belgium

Belgium

International

14

Bellevue (IGN)

Efate and Erromango Islands

International

15

Bermuda 1957

Bermuda Islands

Clarke 1866

16

Bogota Observatory

Colombia

International

121

Bukit Rimpah

Bangka and Belitung Islands (Indonesia)

Bessel 1841

17

Campo Inchauspe

Argentina

International

18

Canton Astro 1966

Phoenix Islands

International

19

Cape

South Africa

Clarke 1880

20

Cape Canaveral

Florida and Bahama Islands

Clarke 1866

1005

Cape, 7 parameter

South Africa

WGS 84

21

Carthage

Tunisia

Clarke 1880

158

CH1903+ datum for Switzerland

Switzerland

Bessel

22

Chatham 1971

Chatham Island (New Zealand)

International

23

Chua Astro

Paraguay

International

122

Coordinate System 1937 of Estonia

Estonia

Bessel 1841

24

Corrego Alegre

Brazil

International

123

Dabola

Guinea

Clarke 1880

156

Dealul Piscului 1970

Romania

Krassovsky

124

Deception Island

Deception Island, Antarctica

Clarke 1880

1000

Deutsches Hauptdreicksnetz (DHDN) Potsdam/Rauenberg

Germany

Bessel

25

Djakarta (Batavia)

Sumatra Island (Indonesia)

Bessel 1841

26

DOS 1968

Gizo Island (New Georgia Islands)

International

27

Easter Island 1967

Easter Island

International

115

EUREF 89

Europe

GRS 80

28

European 1950 (ED 50)

Austria, Belgium, Denmark, Finland, France, Germany, Gibraltar, Greece, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland

International

29

European 1979 (ED 79)

Austria, Finland, Netherlands, Norway, Spain, Sweden, Switzerland

International

108

European 1987 (ED 87)

Europe

International

125

Fort Thomas 1955

Nevis, St. Kitts, Leeward Islands

Clarke 1880

30

Gandajika Base

Republic of Maldives

International

116

GDA 94

Australia

GRS 80

32

Geodetic Reference System 1967 (GRS 67)

Worldwide

GRS 67

33

Geodetic Reference System 1980 (GRS 80)

Worldwide

GRS 80

126

Graciosa Base SW 1948

Faial, Graciosa, Pico, Sao Jorge, and Terceira Islands (Azores)

International 1924

34

Guam 1963

Guam Island

Clarke 1866

35

GUX 1 Astro

Guadalcanal Island

International

150

Hartbeesthoek 94

South Africa

WGS 84

127

Herat North

Afghanistan

International 1924

128

Hermannskogel

Yugoslavia (Prior to 1990), Slovenia, Croatia, Bosnia and Herzegovina, Serbia

Bessel 1841

153

HGRS87


GRS80 (#0)

36

Hito XVIII 1963

South Chile (near 53×S)

International

37

Hjorsey 1955

Iceland

International

38

Hong Kong 1963

Hong Kong

International

1004

Hungarian Datum of 1972 (HD 72)

Hungary

GRS 80

39

Hu-Tzu-Shan

Taiwan

International

40

Indian

Thailand and Vietnam

Everest (India 1830)

41

Indian

Bangladesh, India, Nepal

Everest (India 1830)

129

Indian

Pakistan

Everest (Pakistan)

130

Indian 1954

Thailand

Everest (India 1830)

131

Indian 1960

Vietnam

Everest (India 1830)

132

Indian 1975

Thailand

Everest (India 1830)

133

Indonesian 1974

Indonesia

Indonesian 1974

42

Ireland 1965

Ireland

Modified Airy

134

ISTS 061 Astro 1968

South Georgia Island

International 1924

43

ISTS 073 Astro 1969

Diego Garcia

International

152

JGD2000

Japan

Bessel 1841

44

Johnston Island 1961

Johnston Island

International

45

Kandawala

Sri Lanka

Everest (India 1830)

46

Kerguelen Island

Kerguelen Island

International

47

Kertau 1948

West Malaysia and Singapore

Everest (W. Malaysia and Singapore 1948)

1016

KKJ

Finland

International

135

Kusaie Astro 1951

Caroline Islands, Federated States of Micronesia

International 1924

48

L.C. 5 Astro

Cayman Brac Island

Clarke 1866

136

Leigon

Ghana

Clarke 1880

49

Liberia 1964

Liberia

Clarke 1880

155

Libya (LGD 2006)

Libya

International

113

Lisboa (DLx)

Portugal

International

1018

Lithuanian Pulkovo 1942

Latvia, Lithuania

Krassovsky (#3)

50

Luzon

Philippines (excluding Mindanao Island)

Clarke 1866

51

Luzon

Mindanao Island

Clarke 1866

138

M'Poraloko

Gabon

Clarke 1880

52

Mahe 1971

Mahe Island

Clarke 1880

53

Marco Astro

Salvage Islands

International

54

Massawa

Eritrea (Ethiopia)

Bessel 1841

114

Melrica 1973 (D73)

Portugal

International

55

Merchich

Morocco

Clarke 1880

56

Midway Astro 1961

Midway Island

International

57

Minna

Nigeria

Clarke 1880

137

Montserrat Island Astro 1958

Montserrat, Leeward Islands

Clarke 1880

58

Nahrwan

Masirah Island (Oman)

Clarke 1880

59

Nahrwan

United Arab Emirates

Clarke 1880

60

Nahrwan

Saudi Arabia

Clarke 1880

61

Naparima, BWI

Trinidad and Tobago

International

109

Netherlands

Netherlands

Bessel

1010

New Zealand Geodetic Datum 194, 7 parameter

New Zealand

International

31

New Zealand Geodetic Datum 1949 (NZGD 49)

New Zealand

International

62

North American 1927 (NAD 27)

Continental U.S.

Clarke 1866

63

North American 1927 (NAD 27)

Alaska

Clarke 1866

64

North American 1927 (NAD 27)

Bahamas (excluding San Salvador Island)

Clarke 1866

65

North American 1927 (NAD 27)

San Salvador Island

Clarke 1866

66

North American 1927 (NAD 27)

Canada (including Newfoundland Island)

Clarke 1866

67

North American 1927 (NAD 27)

Canal Zone

Clarke 1866

68

North American 1927 (NAD 27)

Caribbean (Turks and Caicos Islands)

Clarke 1866

69

North American 1927 (NAD 27)

Central America (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua)

Clarke 1866

70

North American 1927 (NAD 27)

Cuba

Clarke 1866

71

North American 1927 (NAD 27)

Greenland (Hayes Peninsula)

Clarke 1866

72

North American 1927 (NAD 27)

Mexico

Clarke 1866

73

North American 1927 (NAD 27)

Michigan (used only for State Plane Coordinate System 1927)

Modified Clarke 1866

74

North American 1983 (NAD 83)

Alaska, Canada, Central America, Continental U.S., Mexico

GRS 80

139

North Sahara 1959

Algeria

Clarke 1880

1022

North Sahara 7-parameter

Algeria

Clarke 1880

107

Nouvelle Triangulation Francaise (NTF) Greenwich Prime Meridian

France

Modified Clarke 1880

1002

Nouvelle Triangulation Francaise (NTF) Paris Prime Meridian

France

Modified Clarke 1880

111

NWGL 10

Worldwide

WGS 72

117

NZGD 2000

New Zealand

GRS 80

75

Observatorio 1966

Corvo and Flores Islands (Azores)

International

140

Observatorio Meteorologico 1939

Corvo and Flores Islands (Azores)

International 1924

76

Old Egyptian

Egypt

Helmert 1906

77

Old Hawaiian

Hawaii

Clarke 1866

78

Oman

Oman

Clarke 1880

79

Ordnance Survey of Great Britain 1936

England, Isle of Man, Scotland, Shetland Islands, Wales

Airy

80

Pico de las Nieves

Canary Islands

International

81

Pitcairn Astro 1967

Pitcairn Island

International

141

Point 58

Burkina Faso and Niger

Clarke 1880

142

Pointe Noire 1948

Congo

Clarke 1880

157

Popular Visualization CRS / Mercator

Worldwide

WGS 84 Sphere

143

Porto Santo 1936

Porto Santo and Madeiras Islands

International 1924

1000

Potsdam

Germany

Bessel

82

Provisional South American 1956

Bolivia, Chile, Colombia, Ecuador, Guyana, Peru, Venezuela

International

36

Provisional South Chilean 1963

South Chile (near 53×S)

International

83

Puerto Rico

Puerto Rico and Virgin Islands

Clarke 1866

1001

Pulkovo 1942

Germany

Krassovsky

84

Qatar National

Qatar

International

85

Qornoq

South Greenland

International

1000

Rauenberg

Germany

Bessel

86

Reunion

Mascarene Island

International

112

Rikets Triangulering 1990 (RT 90)

Sweden

Bessel

1011

Rikets Triangulering 1990 (RT 90), 7 parameter

Sweden

Bessel

87

Rome 1940

Sardinia Island

International

1012

Russia PZ90

Russia

PZ90

1012

Russia PZ90

Russia

PZ90

1013

Russia SK42

Russia

SK95

1014

Russia SK95

Russia

PZ90

88

Santo (DOS)

Espirito Santo Island

International

89

São Braz

São Miguel, Santa Maria Islands (Azores)

International

90

Sapper Hill 1943

East Falkland Island

International

91

Schwarzeck

Namibia

Modified Bessel 1841

159

Schwarzeck (updated ) datum for Namibia

Namibia

Modified Bessel

144

Selvagem Grande 1938

Salvage Islands

International 1924

1021

Serbia datum MGI 1901

Republic of Serbia

Bessel

145

Sierra Leone 1960

Sierra Leone

Clarke 1880

146

S-JTSK

Czech Republic

Bessel 1841

1020

S-JTSK (Ferro prime meridian)

Czech Republic

Bessel #11

92

South American 1969

Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Venezuela, Trinidad and Tobago

South American 1969

93

South Asia

Singapore

Modified Fischer 1960

94

Southeast Base

Porto Santo and Madeira Islands

International

95

Southwest Base

Faial, Graciosa, Pico, Sao Jorge, Terceira Islands (Azores)

International

1003

Switzerland (CH 1903)

Switzerland

Bessel

147

Tananarive Observatory 1925

Madagascar

International 1924

96

Timbalai 1948

Brunei and East Malaysia (Sarawak and Sabah)

Everest (India 1830)

97

Tokyo

Japan, Korea, Okinawa

Bessel 1841

1015

Tokyo97

Japan

Bessel 1841

98

Tristan Astro 1968

Tristan da Cunha

International

99

Viti Levu 1916

Viti Levu Island (Fiji Islands)

Clarke 1880

148

Voirol 1874

Tunisia/Algeria

Clarke 1880

149

Voirol 1960

Algeria

Clarke 1880

100

Wake-Eniwetok 1960

Marshall Islands

Hough

101

World Geodetic System 1960 (WGS 60)

Worldwide

WGS 60

102

World Geodetic System 1966 (WGS 66)

Worldwide

WGS 66

103

World Geodetic System 1972 (WGS 72)

Worldwide

WGS 72

104

World Geodetic System 1984 (WGS 84)

Worldwide

WGS 84

1017

Xian

China

1980

105

Yacare

Uruguay

International

106

Zanderij

Surinam

International

166

Aratu

Brazil

4

167

Barbados

Barbados

6

168

Beduaram

Niger

30

169

Conakry_1905

Guinea

30

170

Dealul Piscului 1930

Romania

4

171

Douala

Cameroon

4

172

Final_Datum_1958

Iran

6

173

Makassar

Indonesia

10

174

Manoca

Cameroon

30

1026

NGO_1948

Norway

1026

1927

Palestine_1923

Asia / Middle East

1027