RT Journal Article
T1 Intra- and inter-field compositional changes of oils from the Misoa B4 reservoir in the Ceuta Southeast Area (Lake Maracaibo, Venezuela)
A1 Márquez Martínez, Gonzalo
A1 Escobar, Marcos
A1 Lorenzo García, Erica
A1 Duno, L
A1 Esquinas, N
A1 Gallego, J. R.
AB Here we analyzed oil samples from 35 wells in the Ceuta Southeast Area (Lake Maracaibo Basin, northwestern Venezuela) in order to evaluate lateral intra-reservoir continuity in the Misoa B4 unit. Biomarkers, isotopic signature, and also V and Ni were examined using gas chromatography-mass spectrometry (GC-MS), isotope ratio mass spectrometry (IRMS), and inductively-coupled plasma atomic emission spectroscopy (ICP-AES). Multivariate statistical analysis was also applied to obtain useful information from geochemical data. On the basis of the characterization of these samples, we conclude that they all fall into various oil families derived from two pulses of hydrocarbon generation, migration and accumulation from the calcareous La Luna source rock, deposited in an anoxic marine environment under reducing conditions. Thus, these oils are a mixture of an earlier biodegraded, less mature oil charge and a later fresh non-biodegraded oil recharge. In addition, we applied asphaltene pyrolysis to one (LG-62) of the three “anomalous” oils. The LG-62 sample was confirmed as an almost “pure” paleobiodegraded end-member, whereas the VLF-3020 oil was tentatively classified as the unaltered end-member oil-type. Finally, the GC fingerprints and Fourier Transform Infra Red (FTIR) spectroscopic indices of the oils were used to detect minor variations in composition that are indicative of reservoir compartmentalization.
PB Elsevier
SN 0016-2361
SN 1873-7153 (electrónico)
YR 2016
FD 2016
LK https://hdl.handle.net/10272/24888
UL https://hdl.handle.net/10272/24888
LA eng
NO Márquez, G., Escobar, M., Lorenzo, E., Duno, L., Esquinas, N., & Gallego, J. R. (2016). Intra- and inter-field compositional changes of oils from the Misoa B4 reservoir in the Ceuta Southeast Area (Lake Maracaibo, Venezuela). In Fuel (Vol. 167, pp. 118–134). Elsevier BV. https://doi.org/10.1016/j.fuel.2015.11.046
NO This study was partially found by the Development Council of the University of Zulia (CONDES-LUZ), through the Research Project No. CC-0555-13. Authors thank J. Amaroy (PDVSA) and A. Lara-Gonzalo for access to the samples and for her assistance, respectively. We are also grateful to the anonymous reviewers for their comments which helped us to improve the original manuscript.
DS Repositorio Institucional de la Universidad de Huelva
RD 30 may 2026