APAALSE - Paper - Caris

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Figure 1: Proprietary data available in GNPC showing seismic coverage of the entire coast. The yellow ovals are areas where the FOS could be located as mapped by GEUS & NCSAC, March 2007. Figure 2: This figure shows the potential extension area of 1,440 km² for Ghana (red) as depicted in Report No. 2003-0233 The GNCSDP considers the preliminary assessment contained in Report No. 2003-0233 as the qualifying criteria for the Test of Appurtenance (TOA) under the requirements of Article 76. Based on this, Robert van de Poll, Fugro Pelagos, was contracted to carry out the desktop study, in consultation with the GNCSDP, under the following scope of work: • Define the Territorial Sea Baseline (Normal Baseline) by generating base points from UK Hydrographic Nautical Charts, Russian Nautical Charts, recently acquired 0.5 m resolution Orthophotos of the entire coastline of Ghana and direct Field Observations. • Delineate adjacent boundaries between Ghana and Cote d’Ivoire, Togo, Benin and Nigeria. • Measure the 200 nautical mile limit and the 350 M constraint line from the baseline • Locate the FOS at the maximum change in gradient at the base of the slope. • Choose the points where the sediment thickness is 1% of the distance to the FOS • Determine the approximate extension area • Recommend any extra data needs for the preparation of the submission to the CLCS Legal Limits The 1986 Maritime Zones (Delimitation) Law, PNDC Law 159, which incorporated the UNCLOS provisions into Ghana’s domestic legislation, declared the following Maritime Zones measured from the Territorial Sea Baseline (TSB): • A Territorial Sea of 12 M, • A Contiguous Zone of 24 M, • An Exclusive Economic Zone (EEZ) not exceeding 200 M, and 4
• A Continental Shelf of up to 200 M. By the same legislation, the Normal Baseline was declared as the official Territorial Sea Baseline as published in the United Nations ‘Table of Claims to Maritime Jurisdiction’, May 2008. Territorial Sea Baseline To proceed with the desktop study, a base map of the area (Figure 3) had to be generated. The 2006 National Geospatial Agency (NGA) WVS2 dataset was used to mimic the coastline at an approximate scale of 1:75000 and an accuracy of ±100 m. This new NGA WVS2 dataset was collected from present-day LANDSAT TM7 Satellite Imagery (14.25 m resolution, accuracy ±50 m, September 2003). It must be pointed out that published base points of coastal States in the study area were not available. However, Cote d’Ivoire and Nigeria have legal legislations for the use of both straight and normal baselines while Togo and Benin have legislations for the use of normal baselines as the TSB. For this reason, ‘hypothetical’ base points and baselines were produced for respective adjacent coasts by digitizing the straight and normal baselines in <strong>Caris</strong> Lots with the help of nautical charts, satellite imagery and orthophotos. Strenuous efforts were made to generate base points for the Ghana TSB. Initially, two United Kingdom Hydrographic Office Nautical Charts Nos.1383 and 1384, published on July 11, 2004 and May 12, 2005 respectively, were used. They are both regional Nautical Charts of 1:350,000 scale, showing generalized coastline with some isolated low water line information (Figure 4). No datum was supplied for these charts and a note on the charts themselves cautions their accuracy. Therefore, a resort was made to three larger scale Russian Nautical Charts (Chart 3500 in 1:150000, Chart 35001 in 1:150,000 and Chart 35005 in 1:50000). Recently acquired 111 0.5 m resolution orthophotos were also supplied by the Survey Department of Ghana to improve the quality of the base points. In the final analysis, 335 base points were computed as geographic coordinates in WGS84 Datum and are now being edited to be submitted to the United Nations for publication and also to be used in adjacent maritime boundary delineation neighbouring coastal States (Cote d’Ivoire to the west, and Togo, Benin and Nigeria to the east). Out of the 335 base points, 28 were collected from the Russian Nautical Charts (see Figure 5 for examples). The remaining 307 were collected from the Orthophotos, examples of which are shown in figures 6 & 7. 5
Page 1 and 2: LawrenceApaalse ProjectCoordinator,
Page 3: work. The preliminary stage which n
Page 7 and 8: Figure 5: Russian Nautical Charts (
Page 9 and 10: Figure 8: Diagram detailing the bas
Page 11 and 12: A review of the over 700 2D SEGY li
Page 13 and 14: Figure 12: Results of the Fine Sedi
Page 15 and 16: However, the GNCSDP, desirous to ma
Page 17 and 18: Conclusions and Recommendations The

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