Regional Geochemical Evaluation of Crude Oils and Source Rocks from The Central Basins Offshore Brazil
GEOCHEMICAL SOLUTIONS INTERNATIONAL INC. (GSI) has conducted a geochemical study of crude oils from the basins along the central margin of Brazil designed to identify and compare the petroleum systems that have contributed to accumulations in this important area. The studied basins include Sergipe-Alagoas, Reconcavo, Camamu-Almada, Jequitinhonha, Cumuruxatiba, Mucuri and Espirito Santo.
Approximately one hundred (100) crude oils from this area have been analyzed using state-of-the-art oil fingerprinting techniques to evaluate the major factors governing oil quality and quantity including: (1) source facies, (2) thermal maturity, (3) distance of migration from source to trap, (4) extent and timing of biodegradation, and (5) degree of oil mixing.
GSI has also conducted a geochemical characterization of potential source rock samples from this area in a study designed to evaluate the organic richness, hydrocarbon-generating potential, oil proneness, and thermal maturity level of all potential source rock intervals in the Camamu-Almada, Jequitinhonha, Cumuruxatiba and Mucuri basins in order to assist exploration efforts in the less developed regions.
Source potential of more than 4,500 samples representing more than 72,000 m of section from more than 35 wells was evaluated based on total organic carbon (%TOC) and Rock-Eval pyrolysis data. Selected well cuttings and/or core samples were further characterized by detailed kerogen and/or bitumen analyses.
Crude oil and source rock analyses were performed at BRI-DGSI laboratories in Houston.
Results of the study are presented in both analytical and interpretive formats to insure that all findings are accessible to explorationists and research personnel. All geochemical data is provided in hard copy and in digital format in a database contained on CD, which includes a proprietary data browser to facilitate access.
A synthesis and interpretation of all information is presented in a series of comprehensive final reports including oil-oil and oil-source rock correlations, oil quality, hydrocarbon source potential, oil proneness and thermal maturity.
For interested companies, basin-specific quantitative modeling studies can be performed as a supplementary product.
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