RT Journal Article
T1 Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain
A1 Marín Barba, P.
A1 Márquez Martínez, Gonzalo
A1 Gallego, J. R.
A1 Permanyer, Albert
A1 Márquez Martínez, Gonzalo
AB A geochemical investigation has been undertaken on biodegraded hydrocarbons in outcropping reservoirsof the south-eastern margin of the Basque-Cantabrian Basin (Álava sector). The aims of the study were thecharacterization of the geochemical features and biodegradation level of these hydrocarbons, and the evaluationof their resemblance to oils from the Ayoluengo onshore oil field by means of isotopic analyses and gaschromatography-mass spectrometry techniques. Most of the samples lack n-alkanes, isoprenoids, low molecularweight aromatic compounds, steranes, homohopanes, diasteranes and triaromatic steroids, whereas hexacyclicand heptacyclic alkanes appear as key compounds although some structures were not totally elucidated. Thermalmaturity has been assessed with several parameters and a calculated-equivalent vitrinite reflectance value ofaround 0.8% was estimated. In addition, gammacerane content, diasterane-to-sterane ratio and C35 to C34 hopanesratio suggest that the Álava oil shows were derived from a carbonate rock deposited in a reducing, water-stratifiedand possibly hypersaline environment. Isotopic signatures and other data confirmed that these hydrocarbons arenot genetically related to the oils from Ayoluengo and, consequently, their origin is associated with a yet unknownsource rock in the basin.
PB Universitat de Barcelona
SN 1695-6133
SN 1696-5728 (electrónico)
YR 2014
FD 2014
LK http://hdl.handle.net/10272/13677
UL http://hdl.handle.net/10272/13677
LA eng
NO Marín Barba, P., Márquez Martínez, G., Gallego, J.R., Permanyer, A.: "Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain". Geologica Acta. Vol. 12, n. 4, págs. 327-342, (2015). DOI: 10.1344/GeologicaActa2014.12.4.4
NO This article is part of the "Alago Special Publication: selected contributions from the XIII Congress". This study was funded by the Ministerio de Ciencia e Innovacion (Research Project CGL2010-15887). We also thank the two reviewers (J.A. Curiale and D. Garcia-Bautista) for their comments which helped to improve the original version of this research work.
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026