Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina
Isotopic analysis can be used to interpret the origin of evaporitic sediments. A preliminary isotopic study of strontium, oxygen and sulphur has been carried out in Ca-sulphate facies of Jurassic marine evaporites (Tábanos Formation and Auquilco Formation) outcropping in southern Mendoza, Aconcagua-...
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2005
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_16956133_v3_n2_p155_LoForte http://hdl.handle.net/20.500.12110/paper_16956133_v3_n2_p155_LoForte |
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paper:paper_16956133_v3_n2_p155_LoForte2023-06-08T16:26:46Z Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina Aconcagua-Neuquén Basin Argentina Isotopic composition Jurassic Marine evaporites evaporite Jurassic Argentina Neuquen Basin South America Western Hemisphere World Isotopic analysis can be used to interpret the origin of evaporitic sediments. A preliminary isotopic study of strontium, oxygen and sulphur has been carried out in Ca-sulphate facies of Jurassic marine evaporites (Tábanos Formation and Auquilco Formation) outcropping in southern Mendoza, Aconcagua-Neuquén Basin (Argentina), as a part of a comprehensive sedimentologic study. The analysed sections are located at arroyo Las Leñitas, Cañada Ancha and arroyo Blanco. Sampled units include laminated, banded, and nodular lithofacies, made up of anhydrite, secondary gypsum and calcite. The mineralogy was studied by conventional petrographic analysis and X-ray diffraction. The 87Sr/86Sr ratio was obtained in six samples, with values ranging from 0.706793 to 0.706839, which match marine calcium-sulphate data of the same age. A similar conclusion may be derived from ten samples analysed for oxygen (δ18O) and sulphur (δ34S) isotopic composition: the obtained values are between + 11.55‰ and + 14.42‰, and between + 17.25‰ and + 18.48‰ respectively. The sedimentologic-stratigraphic evidence and the isotopic data both suggest a marine origin for the Tábanos and Auquilco evaporites, without an analytically detectable contribution of continental waters or hydrothermal solutions. The results also suggest that no isotope fractionation occurred during the primary gypsum-to-anhydrite-to-secondary gypsum transformations. © UB-ICTJA. 2005 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_16956133_v3_n2_p155_LoForte http://hdl.handle.net/20.500.12110/paper_16956133_v3_n2_p155_LoForte |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Aconcagua-Neuquén Basin Argentina Isotopic composition Jurassic Marine evaporites evaporite Jurassic Argentina Neuquen Basin South America Western Hemisphere World |
| spellingShingle |
Aconcagua-Neuquén Basin Argentina Isotopic composition Jurassic Marine evaporites evaporite Jurassic Argentina Neuquen Basin South America Western Hemisphere World Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| topic_facet |
Aconcagua-Neuquén Basin Argentina Isotopic composition Jurassic Marine evaporites evaporite Jurassic Argentina Neuquen Basin South America Western Hemisphere World |
| description |
Isotopic analysis can be used to interpret the origin of evaporitic sediments. A preliminary isotopic study of strontium, oxygen and sulphur has been carried out in Ca-sulphate facies of Jurassic marine evaporites (Tábanos Formation and Auquilco Formation) outcropping in southern Mendoza, Aconcagua-Neuquén Basin (Argentina), as a part of a comprehensive sedimentologic study. The analysed sections are located at arroyo Las Leñitas, Cañada Ancha and arroyo Blanco. Sampled units include laminated, banded, and nodular lithofacies, made up of anhydrite, secondary gypsum and calcite. The mineralogy was studied by conventional petrographic analysis and X-ray diffraction. The 87Sr/86Sr ratio was obtained in six samples, with values ranging from 0.706793 to 0.706839, which match marine calcium-sulphate data of the same age. A similar conclusion may be derived from ten samples analysed for oxygen (δ18O) and sulphur (δ34S) isotopic composition: the obtained values are between + 11.55‰ and + 14.42‰, and between + 17.25‰ and + 18.48‰ respectively. The sedimentologic-stratigraphic evidence and the isotopic data both suggest a marine origin for the Tábanos and Auquilco evaporites, without an analytically detectable contribution of continental waters or hydrothermal solutions. The results also suggest that no isotope fractionation occurred during the primary gypsum-to-anhydrite-to-secondary gypsum transformations. © UB-ICTJA. |
| title |
Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| title_short |
Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| title_full |
Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| title_fullStr |
Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| title_full_unstemmed |
Isotopic characterization of Jurassic evaporites. Aconcagua-Neuquén Basin, Argentina |
| title_sort |
isotopic characterization of jurassic evaporites. aconcagua-neuquén basin, argentina |
| publishDate |
2005 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_16956133_v3_n2_p155_LoForte http://hdl.handle.net/20.500.12110/paper_16956133_v3_n2_p155_LoForte |
| _version_ |
1768543202248228864 |