气候变化领域集成服务门户(CCPortal): Unusual marbles in a non-metamorphic succession of the SW Alps (Valdieri; Italy) due to early Oligocene hydrothermal flow

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DOI	10.1007/s00531-019-01676-z
	Unusual marbles in a non-metamorphic succession of the SW Alps (Valdieri; Italy) due to early Oligocene hydrothermal flow
	Bertok C.; Barale L.; d’Atri A.; Martire L.; Piana F.; Rossetti P.; Gerdes A.
发表日期	2019
ISSN	14373254
起始页码	693
结束页码	712
卷号	108 期号:2
英文摘要	In the SW Alps, at the NE margin of the Argentera Massif, the occurrence of isolated bodies of silicate-bearing marbles (Valdieri Marble), laterally passing to non-metamorphic Mesozoic limestones of the Dauphinois succession, appears enigmatic, since their origin cannot be related to the regional metamorphism. The stratigraphic, geometric, petrographic, and geochemical features of the Valdieri Marble indicate that it originated from the upflow of hydrothermal fluids which deeply recrystallised the limestone and provoked the abundant neoblastesis of silicate minerals, at an estimated crystallisation temperature of ca. 350 °C. This paper provides for the first time an absolute U/Pb age, comprised between 30 and 31.6 Ma (early Oligocene), for the Valdieri Marble, which is affected by a syn-genetic shear foliation in turn crosscut by the main Alpine tectonic foliations. The hydrothermal fluids that formed the Valdieri Marble migrated along low-angle shear zones, mostly parallel to the sedimentary primary bedding, which were downward connected with high-angle master faults of the “Alpine SW transfer”, a main Oligocene–early Miocene transcurrent shear zone at the southern termination of the Western Alps. The localized heat flow sustaining the hydrothermal system could be related to the early Oligocene thermal event, well documented by magmatic activity in the Western and Central Alps. © 2019, Geologische Vereinigung e.V. (GV).
英文关键词	Alpine SW transfer; Dauphinois Domain; Hydrothermal flows; Maritime Alps; U/Pb geochronology; Valdieri Marble
语种	英语
scopus关键词	geochronology; hydrothermal fluid; limestone; marble; Oligocene; shear zone; silicate mineral; uranium-lead dating; Alps; Italy; Calluna vulgaris
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/147865
作者单位	Dipartimento di Scienze della Terra, Università di Torino, via Valperga Caluso 35, Turin, 10125, Italy; CNR IGG-Torino, via Valperga Caluso 35, Turin, 10125, Italy; Department of Geosciences, Goethe University Frankfurt, Frankfurt am Main, 60438, Germany
推荐引用方式 GB/T 7714	Bertok C.,Barale L.,d’Atri A.,et al. Unusual marbles in a non-metamorphic succession of the SW Alps (Valdieri; Italy) due to early Oligocene hydrothermal flow[J],2019,108(2).
APA	Bertok C..,Barale L..,d’Atri A..,Martire L..,Piana F..,...&Gerdes A..(2019).Unusual marbles in a non-metamorphic succession of the SW Alps (Valdieri; Italy) due to early Oligocene hydrothermal flow.International Journal of Earth Sciences,108(2).
MLA	Bertok C.,et al."Unusual marbles in a non-metamorphic succession of the SW Alps (Valdieri; Italy) due to early Oligocene hydrothermal flow".International Journal of Earth Sciences 108.2(2019).