RT info:eu-repo/semantics/article
T1 The Esquinzo Ultra-Alkaline Rock Suite of Fuerteventura Basal Complex (Canary Islands): Evidence for Origin of Carbonatites by Fractional Crystallization
A1 Casillas, Ramón
A1 Ahijado, Agustina
A1 Nagy, Géza
A1 Demény, Attila
A1 Fernández, Carlos
K1 Fuerteventura
K1 carbonatite
K1 fractional crystallization
K1 oceanic island
K1 melanephelinite
AB The origin of the carbonatites that appear on Earth is one of the most controversial currenttopics in the petrogenesis of igneous rocks. Situated in the northern sector of the Basal Complexof Fuerteventura (Canary Islands), the Miocene Esquinzo ultra-alkaline plutonic rock complex iscomposed of pyroxenites, melteigites-ijolites-urtites, malignites-nepheline syenites, carbonatites,silicocarbonatites, nephelinites and nepheline phonolites. This work tries to establish the genesis ofthis massif of ultra-alkaline rocks with associated carbonatites from Fuerteventura (which are veryrare in the oceans). The geochemical characteristics of these rocks and the minerals that are includedin them have allowed us to establish their origin. This complex was generated by three successivemagmatic events associated with differentiation of melanephelinite magmas emplaced in the oceaniccrust. Silicocarbonatite and calciocarbonatite (sövites) dykes are related to the first magmatic eventand were formed by fractional crystallization of H2O- and CO2-rich ijolite magmas. The melanephelinitemagmas that formed these plutonic ultra-alkaline rocks were apparently generated as partialmelts of asthenospheric mantle, which assimilated enriched lithospheric mantle material as theyascended. The upwelling of this large body of anomalous asthenospheric Miocene material exceededthe deformation associated with plate motions and led to an oceanic rifting event in Fuerteventura.
YR 2024
FD 2024
LK http://riull.ull.es/xmlui/handle/915/38017
UL http://riull.ull.es/xmlui/handle/915/38017
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 23-nov-2024