THIS MAIL IS UNCLASSIFIED RE: ICJ Ruling on Land and Maritime Boundary between Cameroon and Nigeria
Dear List Members
A copy
of Admiralty chart 3433 (Approaches to Calabar - Sheet 1, scale 1:50 000) was
annexed to the Yaounde II and Maroua Declarations signed by the Heads of
State of Cameroon and Nigeria on 4 April 1971 and 1 June 1975
respectively.
It is surprising that chart 3433, a large-scale
chart, contains no reference to the datum to which coordinates
scaled from this chart are to be referred. Undoubtedly this is the reason
why the texts of the Yaounde II and Maroua Declarations also contain no
reference to the datum to which the geographical coordinates included
therein are to be referred. What this really means is that it may be
virtually impossible to accurately define the subject boundary turning points,
as defined by the agreed geographical coordinates, "on the ground". Mr
Carleton's brief comments confirm that chart 3433 is not referred to any datum
(i.e. it is "datum nullius") and that there are no block shift
parameters published on the face of the chart enabling scaled coordinates
to be converted to coordinates in terms of a modern geocentric reference system,
such as WGS 84. It is surmised that the datum used for this chart is
either a local astronomically determined datum or a local geodetic datum, such
as the Adindan or Minna datums etc., but who really knows?
However, given the likely age of the chart, the former
is the more likely. If this is the case, then the absolute
positioning of features and points of detail (e.g. soundings) depicted on
the face of the chart could be many hundreds of metres, possibly up to 1
nautical mile, different to positions of the same features as determined by
means of the Global Positioning System (GPS) in terms of the WGS 84 reference
system.
With the utmost respect, the ICJ decision has
effectively perpetuated the problems associated with the omission of a reference
datum from Admiralty chart 3433 upon which the coordinates included in the
Yaounde II and Maroua Declarations totally depend. The ICJ decision
to uphold the validity of these two declarations, while making no reference to
the datum to which coordinates defined in that decision are to be referred, only
serves to further exacerbate the problem.
Regards
Brian Murphy
GeoFix Pty Ltd
ABN 98 084 393 353
4/115 Crisp
Circuit
Bruce A.C.T.
2617
Australia
Phone: +61 2 6251
5312
+61 2 6253 3500
Facsimile: +61 2 6253 5800
----- Original Message -----
Sent: Saturday, October 12, 2002 12:25
AM
Subject: Re: ICJ Ruling on Land and
Maritime Bou ndary between Cameroon and Nigeria
Ladies and Gentlemen,
As a matter
of interest there is no known datum on Admiralty chart 3433 as it quite
clearly states in the title block. This makes the co-ordinates listed in the
judgement somewhat problematical.
Kindest Regards
Chris Carleton
CHRIS CARLETON, MBE, MILA, MRICS
Head,
Law of the Sea Division
UK Hydrographic Office
[log in to unmask]
-----Original Message-----
From: Bob
Ballard [mailto:[log in to unmask]]
Sent: 11 October 2002 15:12
To: [log in to unmask]
Subject: Re:
ICJ Ruling on Land and Maritime Boundary between Cameroon and Nigeria
Mr. Gurdon,
Thank you for the detail on the referenced ICJ ruling.
One question,
there is no formal indication of datum
for all the coordinates presented
in the document,
unless I missed it. In various locations, mention of
charts are made as in:
"...drawn jointly at Yaoundé on 4 April 1971 by the Heads of
State of
Cameroon and Nigeria on British Admiralty
Chart 3433..." and
"The Court, having carefully studied a variety of charts,
observes..."
and
"...the boundary follows the "compromise line" drawn jointly
at Yaoundé
on 4 April 1971 by the Heads of State of
Cameroon and Nigeria on British
Admiralty Chart
3433..."
Are indeed these 'modern' offshore boundary coordinate sets to
be
referred to the same datum as the 1971 version of
Admiralty Chart #3433?
Regards
Bob Ballard
Plano, TX
