Kaersutite megacrysts in the alkaline mafic dikes of the Panticosa pluton (Pyrenean Axial Zone, Spain): deep-origin xenocrysts

Megacrysts of kaersutite have been identified in several alkaline mafic dikes from the Panticosa pluton. They show strongly anhedral habits and resorption features, including Krs overgrowths and/or Cpx-Opq coronae. Chemically, the liquid in equilibrium with the megacryst cores is clearly different f...

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Detalles Bibliográficos
Autores: Tierz, Pablo, Lago San José, Marceliano, Galé, Carlos, Arranz, Enrique, Ubide, Teresa, Larrea, Patricia, Sanz, Tomás
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Universidad de Huelva (UHU)
Repositorio:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:inglés
OAI Identifier:oai:ariasmontano.uhu.es:10272/7251
Acceso en línea:http://hdl.handle.net/10272/7251
Access Level:acceso abierto
Palabra clave:Kaersutite
Dike
Alkaline
Permian
Pyrenees
Kaersutita
Dique
Alcalino
Pérmico
Pirineos
Descripción
Sumario:Megacrysts of kaersutite have been identified in several alkaline mafic dikes from the Panticosa pluton. They show strongly anhedral habits and resorption features, including Krs overgrowths and/or Cpx-Opq coronae. Chemically, the liquid in equilibrium with the megacryst cores is clearly different from the host alkaline dikes. In contrast, the liquid in equilibrium with Krs overgrowths and Cpx from the coronae agrees with the composition of some of the host alkaline dikes. According to the obtained results, Krs megacrysts must be considered xenocrysts. Therefore, their Middle Permian age (268 Ma) predates the emplacement of the alkaline dikes. The xenocrysts crystallised at about 30 km depth and were afterwards reequilibrated at lower depths