A new style of Ni-Cu mineralization related to magmatic breccia pipes in a transpressional magmatic arc, Aguablanca, Spain

The Aguablanca deposit represents a new style of magmatic Ni Cu mineralization in discordant sulfide rich pyro xenitic breccia pipes. The orebody is hosted by Variscan calc alkaline diorites and gabbros which intruded during an oblique subduction/collision event. Transpressional transtensional left...

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Detalles Bibliográficos
Autores: Tornos Arroyo, Fernando, Casquet Martín, César, Galindo Francisco, María Del Carmen, Velasco Roldán, Francisco, Canales Gallarosa, Ángel
Tipo de recurso: artículo
Fecha de publicación:2001
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/56972
Acceso en línea:https://hdl.handle.net/20.500.14352/56972
Access Level:acceso abierto
Palabra clave:549.3(460.253)
Ni-Cu mineralitation
Aquablanca
Spain
Geoquímica
2503 Geoquímica
Descripción
Sumario:The Aguablanca deposit represents a new style of magmatic Ni Cu mineralization in discordant sulfide rich pyro xenitic breccia pipes. The orebody is hosted by Variscan calc alkaline diorites and gabbros which intruded during an oblique subduction/collision event. Transpressional transtensional left lateral structures facilitated the intrusion of primitive magmas to shallow depths in the crust. A two stage genetic model is proposed. In the first stage, a transitional deep magma chamber formed. The primitive magma interacted at depth with wall rocks, resulting in extensive crustal contamination, concomitant sulfide magma immiscibility and settling of orthopyroxene , clinopyrox ene and sulfide rich cumulates to form a layered magmatic complex. Geochemical and mineralogical evidence, including the virtual disappearance of olivine, heavy 34S values (7.4‰), distinctive Nd, Sr and Pb signatures, high Au contents, and the presence of spinel and graphite indicate a major interaction with the upper crust, probably with pyrite rich carbonaceous slates of Late Proterozoic age. The second stage was related with the emplacement of residual calc alkaline gabbroic to noritic melts and the development of an intrusive breccia containing fragments of the consolidated layered complex rocks and associated disseminated to massive sulfides