Las rocas volcánicas neógenas de Nuévalos (provincia de Zaragoza)

On the basis of petrological data, the ultra-alkaline character of the volcanics from Nuévalos is clearly pointed out. This character rejects any type of relationship with Permian and Mesozoic volcanic events. Furthermore, analogies with plio-quaternary volcanics from Cofrentes suggest a similar epi...

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Detalhes bibliográficos
Autores: Ancochea, Eumenio, Sagredo, J., Muñoz, Mercedes
Formato: artículo
Fecha de publicación:1987
País:España
Recursos:Universidad de Huelva (UHU)
Repositorio:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:español
OAI Identifier:oai:ariasmontano.uhu.es:10272/18425
Acesso em linha:http://hdl.handle.net/10272/18425
Access Level:acceso abierto
Palavra-chave:Vulcanism
Olivine nephelinites
Partial melting
Upper mande
Descrição
Resumo:On the basis of petrological data, the ultra-alkaline character of the volcanics from Nuévalos is clearly pointed out. This character rejects any type of relationship with Permian and Mesozoic volcanic events. Furthermore, analogies with plio-quaternary volcanics from Cofrentes suggest a similar episode related to a tensional regime that can be linked to the openning of the Valencia gulf. The volcanics are massive and look a porphyritic crystalline texture. Mineralogical composition define them as olivine-nephelinite rocks. They have a large amount of xenocrysts from mantle spinel-peridotite. The high xenocryst accumulation percentage has modified the original character of the primary melt The whole geochemical data suggest a parental magma derived by a very Iow degree of melting (4,3%) from a peridotitic mande source, strongly enriched in incompatible elements, and from a depth near to 700 km.