CARACTERIZACIÓN DE BIOMARCADORES EN CRUDOS Y RESINAS TIPO I, OCLUIDAS EN LA FRACCIÓN DE ASFALTENOS

Some structural features of asphaltenes, such as its high porosity, enable them to adsorb and occlude other organic species1, 2. This phenomenon can preserve some of these compounds, which tend to be used as biomarkers, to secondary alteration processes of crude oil in the reservoir. In this study, biomarkers from six samples of Venezuelan crude oils, were analyzed by gas chromatography using a FID detector, in the fraction of maltenes and in resins type I, in order to compare the biomarkers obtained for each fraction. In crude oils with biodegradation, we obtained in the chromatograms of the resins type I, a normal distribution of n-alkanes in the range of n-C16 until n-C34, while in maltenes, was not observed the same distribution and was presented the unresolved mixture of compounds. For non-biodegraded crude oils, were observed similar distributions of nalkanes and values of the ratio pristane / phytane, with some specific differences.