The geochemical study of the sequences of 3rd order of the East of the margin of Abidjan permitted to identify the source rocks of the albian deposits. The pyrolytic methods applied to 30 samples of cuttings, from the drillings Freedom 1 and 2, revealed three types of organic matter at the early of maturity, the types III, II/III and II in the sequences. The variation of the origin of the organic matter in the systems tracts of the sequences testifies a change in the environment of deposit in phase with the eustatic fluctuations. The passage from the type III or II/III to the type II, eventually coupled with a rise of the values of the TOC and/or S2, in this study, evokes a rise in the marine level which would support the good conditions of safeguarding of the organic matter. The albian source rocks in the drilling Freedom 1 are bad source rocks whereas those in the drilling Freedom 2 are good producing source rocks of oil and/or gas hydrocarbon.
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