São Tomé Exclusive Economic Zone
ERHC has a 100 percent working interest in Blocks 4 and 11 of the São Tomé and Príncipe Exclusive Economic Zone (EEZ) free of signature bonuses.
The close proximity of São Tomé and Príncipe’s offshore waters to the proven hydrocarbon systems in the adjacent territorial waters of Gabon, Cameroon, Equatorial Guinea and Nigeria suggests the potential for hydrocarbons, which is further supported by seismic data and petroleum seeps seen on the island of São Tomé. Seismic data for EEZ Blocks 4 and 11 contain highly prospective structures.
ERHC believes the EEZ has all the necessary components of a successful petroleum system. The region is at present unlicensed and undrilled, providing an excellent frontier exploration opportunity. See our EEZ photo album.
Background
ERHC’s involvement in the São Tomé and Príncipe oil and gas industry stretches back to 1997 when the Company was initially granted an oil and gas exploration concession. In 2001, São Tomé and Príncipe awarded ERHC preferential rights in the EEZ. Prior to the opening of the EEZ’s 1st Licensing Round in early 2010, ERHC exercised its rights and the National Petroleum Agency of São Tomé & Príncipe (ANP-STP) on behalf of the Government of São Tomé and Principe confirmed the Block awards.
The islands of São Tomé and Príncipe are located in the eastern Gulf of Guinea approximately 200 km south of Nigeria and directly west of the territorial waters of Equatorial Guinea and Gabon. They compose part of a north-east south-west trending chain of islands in the Eastern Gulf of Guinea
extending offshore from Cameroon. The extensive adjacent deepwater areas of the EEZ are prospective and are undrilled.
The map at right is EEZ Block 4, which totals 5,808 square km, situated directly east of the island of Príncipe. The northeastern area near EEZ Block 4 contains a large graben structure, which is bound by the Kribi Fracture Zone. Click on the map to zoom in.
The lower map is EEZ Block 11. It totals 8,941 square km, situated directly east of the island of São Tomé and abuts the territorial waters of Gabon. The Southern area, where EEZ Block 11 is situated, contains parts of the Ascension and Fang Fracture Zones.Click on the map to zoom in.
The maritime boundaries of São Tomé and Príncipe encompass an area of approximately 160,000 square km. The São Tomé and Príncipe EEZ is a frontier region that sits south of the Niger Delta, and west of the Gabon Salt Basin, retaining similarities with each.
Interpretation of 2D seismic data from the deepwater EEZ area of Sâo Tomé and Príncipe has led to a regional understanding of the subsurface geology, trapping styles and prospectivity within the region of investigation. Additionally, oil sampling of seeps observed on the island of São Tomé has suggested the occurrence of a Late Cretaceous petroleum system.
The ANP-STP has indicated that it expects to invite ERHC to negotiate Production Sharing Contracts (PSCs) on the two Blocks in due course.
ERHC will be responsible for its proportionate share of exploration and exploitation costs in the EEZ blocks.



