Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain
A geochemical investigation has been undertaken on biodegraded hydrocarbons in outcropping reservoirs of the south-eastern margin of the Basque-Cantabrian Basin (Álava sector). The aims of the study were the characterization of the geochemical features and biodegradation level of these hydrocarbons...
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| Format: | Article |
| Language: | English |
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Universitat de Barcelona (UB), Geociències Barcelona (Geo3BCN), Institut de Diagnosi Ambiental i Estudis de l'Aigua (IDAEA), Universitat Autònoma de Barcelona (UAB)
2014-10-01
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| Series: | Geologica Acta |
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| Online Access: | https://revistes.ub.edu/index.php/GEOACTA/article/view/10101 |
| _version_ | 1797654620489646080 |
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| author | P. MARÍN G. MÁRQUEZ J.R. GALLEGO A. PERMANYER |
| author_facet | P. MARÍN G. MÁRQUEZ J.R. GALLEGO A. PERMANYER |
| author_sort | P. MARÍN |
| collection | DOAJ |
| description |
A geochemical investigation has been undertaken on biodegraded hydrocarbons in outcropping reservoirs of the south-eastern margin of the Basque-Cantabrian Basin (Álava sector). The aims of the study were the characterization of the geochemical features and biodegradation level of these hydrocarbons, and the evaluation of their resemblance to oils from the Ayoluengo onshore oil field by means of isotopic analyses and gas chromatography-mass spectrometry techniques. Most of the samples lack of n-alkanes, isoprenoids, low molecular weight aromatic compounds, steranes, homohopanes, diasteranes and triaromatic steroids whereas hexacyclic and heptacyclic alkanes appear as key compounds although some structures were not totally elucidated. Thermal maturity has been assessed with several parameters and thus a calculated-equivalent vitrinite reflectance value of around 0.8% was estimated. In addition, gammacerane content, diasterane-to-sterane ratio and C35 to C34 hopanes ratio suggested that the Álava oil shows were derived from a carbonate rock deposited in a reducing, water-stratified and possibly hypersaline environment. Isotopic signature and other data confirmed that these hydrocarbons are not genetically related to the oils from Ayoluengo and, consequently, their origin has to be associated with a yet unknown source rock in the basin.
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| first_indexed | 2024-03-11T17:02:09Z |
| format | Article |
| id | doaj.art-513971bfee714c5e97219f9cf3d44fa5 |
| institution | Directory Open Access Journal |
| issn | 1696-5728 |
| language | English |
| last_indexed | 2024-03-11T17:02:09Z |
| publishDate | 2014-10-01 |
| publisher | Universitat de Barcelona (UB), Geociències Barcelona (Geo3BCN), Institut de Diagnosi Ambiental i Estudis de l'Aigua (IDAEA), Universitat Autònoma de Barcelona (UAB) |
| record_format | Article |
| series | Geologica Acta |
| spelling | doaj.art-513971bfee714c5e97219f9cf3d44fa52023-10-20T07:20:41ZengUniversitat de Barcelona (UB), Geociències Barcelona (Geo3BCN), Institut de Diagnosi Ambiental i Estudis de l'Aigua (IDAEA), Universitat Autònoma de Barcelona (UAB)Geologica Acta1696-57282014-10-01124Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, SpainP. MARÍN0G. MÁRQUEZ1J.R. GALLEGO2A. PERMANYER3Department of Geochemistry, Petrology and Geological Prospecting, University of Barcelona. C/ Martí i Franquès s/n, 08028-Barcelona, Spain.Departmento de Ingeniería Minera, Mecánica y Energética, Universidad de Huelva. C/ La Rábida s/n, 21819-Huelva, Spain.Departmento de Explotación y Prospección de Minas, Universidad de Oviedo. C/ Gonzalo Gutiérrez Quirós, 33600-Mieres, Spain.Department de Geologia, Petrologia i Prosprecció Geològica, Universitat de Barcelona. C/ Martí i Franquès s/n, 08028-Barcelona, Spain. A geochemical investigation has been undertaken on biodegraded hydrocarbons in outcropping reservoirs of the south-eastern margin of the Basque-Cantabrian Basin (Álava sector). The aims of the study were the characterization of the geochemical features and biodegradation level of these hydrocarbons, and the evaluation of their resemblance to oils from the Ayoluengo onshore oil field by means of isotopic analyses and gas chromatography-mass spectrometry techniques. Most of the samples lack of n-alkanes, isoprenoids, low molecular weight aromatic compounds, steranes, homohopanes, diasteranes and triaromatic steroids whereas hexacyclic and heptacyclic alkanes appear as key compounds although some structures were not totally elucidated. Thermal maturity has been assessed with several parameters and thus a calculated-equivalent vitrinite reflectance value of around 0.8% was estimated. In addition, gammacerane content, diasterane-to-sterane ratio and C35 to C34 hopanes ratio suggested that the Álava oil shows were derived from a carbonate rock deposited in a reducing, water-stratified and possibly hypersaline environment. Isotopic signature and other data confirmed that these hydrocarbons are not genetically related to the oils from Ayoluengo and, consequently, their origin has to be associated with a yet unknown source rock in the basin. https://revistes.ub.edu/index.php/GEOACTA/article/view/10101Asphaltic oil occurrencesBasque-Cantabrian BasinÁlava sectorAyoluengo oil fieldBiodegradation |
| spellingShingle | P. MARÍN G. MÁRQUEZ J.R. GALLEGO A. PERMANYER Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain Geologica Acta Asphaltic oil occurrences Basque-Cantabrian Basin Álava sector Ayoluengo oil field Biodegradation |
| title | Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain |
| title_full | Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain |
| title_fullStr | Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain |
| title_full_unstemmed | Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain |
| title_short | Characterization of asphaltic oil occurrences from the southeastern margin of the Basque-Cantabrian Basin, Spain |
| title_sort | characterization of asphaltic oil occurrences from the southeastern margin of the basque cantabrian basin spain |
| topic | Asphaltic oil occurrences Basque-Cantabrian Basin Álava sector Ayoluengo oil field Biodegradation |
| url | https://revistes.ub.edu/index.php/GEOACTA/article/view/10101 |
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