UNITED NATIONS
ECONOMIC AND
SOCIAL COUNCIL
Distr.
LIMITED
E/CH.H/CART/172 26 August 1966
Original: ENGLISHECONOMIC COMMISSION FOR AFRICA Second United Nations Regional Cartographic,Conference for Africa
Tunis (Tunisia) 12-24 September 1966
Provisional agenda item 7
1:50,000 TOPOGRAPHIC MAPPING OF NIGERIA
PROGRESS REPORT 3l/l2/62 - 31/12/65
Submitted by the Government of Nigeria
M6 6-1200
E/CN.14/CART/172
t
1*50,000 TOPOGRAPHIC MAPPING OF NIGERIA
PROGRESS REPORT 3l/l2/62 - 3l/l2/65
Two maps (Map I and Map II) showing the progress in the 1:50,000 Topographic Mapping (contoured) from 31st December 1962 to 31st December
I965 are attached. This period has shown considerable progress, aris ing not only from a greater emphasis on topo—mapping on the partof the Kigerian Survey Departments but also from the technical assis/fc- anoe received from the governments of Canada and the United Kingdom.
In the case of Canada, the mapping has been done by a private firm under contract to the Canadian Government while for the United Kingdom
the mapping has been carried out by a government department. Other limited assistance has been received from the Netherlands, which country through its International Training Centre for Aerial Surveys
at Delft, is now providing minor control points (using aero—triangula- tion) for nine sheets.
In more detail, Map I shows that at the end of 19^2, 10 sheets
had been compiled or published. Since the end of 1962, a total of87 sheets has now been compiled while a further 45 a^© in different
stages of compilation. Map II shows the position at the end of
In all cases, planimetric control has been based on the national primary triangulation framework. This has been supplemented locally by secondary and tertiary triangulation, limited trilateration, oom- monly Tellurometer distance with azimuth or angle from a primary side and, in the instance of Canadian Technical Assistance, by a limited use of aerodist. It should be mentioned that the primary triangulation though acourate enough for the 1:50,000 series is
presently being checked by the use of latitude, longitude and azimuth observations, at a number of chain figure Junctions, prior to final
adjustment of the triangulation. The progress of these checks (at 31st December 1965) is indicated on the triangulation Map III.
Vertical control is similarly based on the national geodetic level network, the progress of which is shown on Map IV. Mapping
E/CN.14/CART/l72
Page 2
control has "been provided "by a "breakdown of the geodetic framework into secondary and tertiary lines. A wide use has also been made of altimetry for this particular mapping scale. More recently, the Canadians have used APR and horizon data in order to cut down the amount of field work required.
Finally^ it should "be added that good photographic coverage
at 1:40,000 scale is now available for about 80 per cent of the
country as shown on Map V and its absence is only very locally hold
ing up the progress of the topographical mapping programme.NIGERIA 1:5,000,000
1 :50,000 TOPOGRAPHIC MAPPING (CONTOURED) 31. 12. 62 MAP I
---H-- X-f- h + --
■:*-■-•*— —tfc™t
REFERENCE Compilation in progress Compiled or published
12*
Published by National Surveys. Nigeria, 1966.
COPYRIGHT RESERVED.
MILES 100
SCALE 1:5.0^1,000 OR 78.90 MILES TO AN INCH
100 200 300 400
Drawn & printed by National Surveys. Nigeria. 1966.
900/6? 1/6-66.
S00 MILES
NIGERIA 1:5,000,000
1:50,000 TOPOGRAPHIC MAPPING (CONTOURED) 31. 12. 65. MAP II
10'
G U L F 0 F GUINEA
REFERENCE Compilation in progress Compiled or published
12- 1*'
Published by National Surveys. Nigeria, 1966.
COPYRIGHT RESERVED.
MILES 100 0
SCALE 1 :5,000.000 OR 78.90 MILES TO AN INCH
100 200 300 400
Drawn & pnnttd by National Survayi, Nigaria, 1966.
900/670/7-66.
500 MILES I
NIGERIA 1:5,000,000
PRIMARY TRIANGULATION AND TRAVERSES as at 31.12.65. MAP III
REFERENCE Triariguiatron
Traverse
Scale checks measurement completed Astro observation completed
Astro station beaconed but not observed / \ Proposed figure for Scale checks measurements and
Astro observations *
GULF of GUINEA
12°
Published by National Surveys. Nigeria. 1966.
COPYRIGHT RESERVED.
MILES 100 0
I—LJ—i l 1 i—i—i i_L
5CALE 1:5,000.000 OR 78.90 MILES TO AN INCH
100 200 300 400
Drawn and printed by National Surveys. Nigeria, 1966.
900, 7S2/S-64.
500 MILES
NIGERIA 1:5,000,000
LEVELLING as at 31. 12.65. MAP IV
14° C H A D
BIGHT 0
GULF OF GUINEA
REFERENCE
Second order levelling 1928-45
First order levelling complex Miv l95S-M»rch 1961
Geodetic levelling bench marked but not yet levelled
Geodetic levelling completed April 1961-Dec
Connections to International d»tum-completed
Connections to International
datum-propoied ,
Connections to Tideguages..
Geodetic levelling propoied
—o
10"
F.N, MISC. 1 Fifth Edition
Published by National Surveys. Nigeria. 1966.
COPYRIGHT RESERVED.
MILES 100 0
1—I—I—I—I—I—I—1—i—L-J_
SCALE 1:5,000.000 OR 78.90 MILES TO AN INCH
100 200 300 400
Drawn & printed by National Survayi. Nigeria. 1966.
900 17931 Z-bt
500 MILES
NIGERIA 1:5,000,000
COVERAGE OF AERIAL PHOTOGRAPHS 1:40,000 MAP V
CHAD
BIGHT o
GULF OF GUINEA
REFERENCE
Coverage Prior to 1965 Conference.
New 1965 Canadian Tech. A.d (CAS.
Coverage.
No recent Coverage.
New 1965 Huntings Coverage.
1:25.000 Scale Coverage (1964) for Oil Companies.
■
BIGHT of
12" 14'
Published by National Surveys. Nigeria. 1966.
COPYRIGHT RESERVED. Drawn & printed by National Survayi, Nigeria. 1966.
900/ 791/8-66
MILES tOO 0
t—L ]—I—I I I I i i I
SCALE 1:5,000.000 OR 78.90 MILES TO AN INCH
100 200 300 400 500 MILES
