气候变化领域集成服务门户(CCPortal): 87 Sr/ 86 Sr applied to age discrimination of the Palaeozoic carbonates of the Ossa-Morena zone (SW Iberia Variscides)

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DOI	10.1007/s00531-019-01688-9
	87 Sr/ 86 Sr applied to age discrimination of the Palaeozoic carbonates of the Ossa-Morena zone (SW Iberia Variscides)
	Moreira N.; Pedro J.; Santos J.F.; Araújo A.; Dias R.; Ribeiro S.; Romão J.; Mirão J.
发表日期	2019
ISSN	14373254
英文摘要	Four distinct Palaeozoic episodes of marine carbonate sedimentation are reported in the Ossa-Morena Zone (SW Iberian Variscides). Among them, the Cambrian and the Devonian episodes are those that are well represented in the Portuguese domains of the Ossa-Morena zone. In this zone, the strong Variscan deformation and metamorphic recrystallization obliterate the biostratigraphic contents of some carbonate local successions and their ages have been based on lithostratigraphic correlations. The 87 Sr/ 86 Sr values for the Ossa-Morena zone carbonate rocks allow to make an isotopic–lithostratigraphic correlation, based on the comparison between strontium ratios of marine carbonate rocks without chronological data and carbonate rocks with a good age control. Moreover, the established 87 Sr/ 86 Sr fingerprints of the marine carbonate episodes from Ossa-Morena zone should be simultaneously correlated with the worldwide seawater 87 Sr/ 86 Sr curve. Despite the interaction of the marine carbonate sedimentation with late secondary dolomitization processes or with high-temperature metamorphic/metasomatic fluids, which increases the primary 87 Sr/ 86 Sr ratios, this methodology allows to define two main distinct clusters of 87 Sr/ 86 Sr for the Ossa-Morena zone marine carbonates: a Devonian cluster with strontium ratios lower than 0,708000; and a Cambrian cluster ranging from 0.708777 to 0.708299 (0.708575 ± 0,000161), that can reach 0.709227–0.708866 (0.709087 ± 0,000118) if incipient late secondary dolomitization or high-temperature metamorphism/metasomatism operated. The obtained 87 Sr/ 86 Sr isotopic ratios corroborate the lithostratigraphic correlations between the carbonate rocks of Abrantes, Assumar, Estremoz, Viana-Alvito, Ficalho and Escoural successions with the Ovetian–Marianian limestones of Alter-do-Chão–Elvas Succession. Moreover, this methodology allows to establish the isotopic discrimination between the Upper Silurian–Devonian limestones of Ferrarias, Barrancos and Bencatel successions and the marbles of Estremoz Succession. © 2019, Geologische Vereinigung e.V. (GV).
英文关键词	87 Sr/ 86 Sr ratio; Carbonate sedimentation; Iberian variscides; Ossa-Morena zone
语种	英语
来源期刊	International Journal of Earth Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/147900
作者单位	Earth Sciences Institute, Pole of the University of Évora, Rua Romão Ramalho, no. 59, Évora, 7000-671, Portugal; Departamento de Geociências da ECTUE, Colégio Luís António Verney, Rua Romão Ramalho, 59, Évora, 7000-671, Portugal; GeoBioTtec, Departamento de Geociências and Laboratório de Geologia Isotópica, Universidade de Aveiro, Aveiro, 3810-193, Portugal; Laboratório Nacional de Energia e Geologia, UGCG, Estrada da Portela, Apartado 7586, Zambujal, 2720, Alfragide, Portugal; Laboratório HERCULES, Instituto de Investigação e Formação Avançada, Largo Marquês de Marialva, 8, Palácio do Vimioso, Évora, 7000-089, Portugal
推荐引用方式 GB/T 7714	Moreira N.,Pedro J.,Santos J.F.,et al. 87 Sr/ 86 Sr applied to age discrimination of the Palaeozoic carbonates of the Ossa-Morena zone (SW Iberia Variscides)[J],2019.
APA	Moreira N..,Pedro J..,Santos J.F..,Araújo A..,Dias R..,...&Mirão J..(2019).87 Sr/ 86 Sr applied to age discrimination of the Palaeozoic carbonates of the Ossa-Morena zone (SW Iberia Variscides).International Journal of Earth Sciences.
MLA	Moreira N.,et al."87 Sr/ 86 Sr applied to age discrimination of the Palaeozoic carbonates of the Ossa-Morena zone (SW Iberia Variscides)".International Journal of Earth Sciences (2019).