A well-placed source said the Chinese-based outfit BGP is fighting it out with the Geophysical Institute of Israel (GII) over the Cabinda South survey.
BGP (the Bureau of Geophysical Prospecting) is understood to have the edge over Lod-based GII because it is currently working for French independent Maurel & Prom just across the border in neighbouring Congo-Brazzaville.
Roc, headed by chief executive John Doran, is expected to make a decision soon and recommend its favoured contractor to the Angolan authorities in time for operations to begin either this month or next.
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