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 |