RT Journal Article T1 Preliminary apatite-fission track geochronology of the Montaña Blanca-Milocho, alkaline pluton, (NW Fuerteventura, Canary Islands, Spain) A1 Ignacio San José, Cristina de A1 Muñoz García, Mercedes A1 Sagredo Ruiz, Juana A1 Barbero González, Luis C. AB The mafic-ultramafic, alkaline Montana Blanca-Milocho pluton, which is part o f the northernmost outcrop of the Basal Complex of the island of Fuerteventura, Canary Islands, is spatially associated to the Jablitos alkaline-carbonatitic complex. Alkaline clinopyroxenites occurring in the periphery o f both intrusive bodies bear strong petrographic, mineralogical and geochemical similarities. However, the study o f a possible genetic relationship between them was so far hindered by the complete absence of geoclironological data. High apatite abundances in these rocks has allowed the application o f the fission track techniques as a geoclironological tool. Nevertheless, in samples were perovskite occurs the lack o f U in apatite, the K-Ar method had to be used. The 25 and 29 Ma fission tracks central ages obtained are well in agreement with theexpected emplacement age o f these shallow intrusive rocks, and also with published and new K-Ar ages. Thus, a genetic relationship between these ultramafic alkaline clinopyroxenites is here proposed. PB Sociedad Geológica de España. SN 1576-5172 YR 2002 FD 2002 LK https://hdl.handle.net/20.500.14352/57936 UL https://hdl.handle.net/20.500.14352/57936 LA spa NO Dirección General de Investigación Científica y Técnica DS Docta Complutense RD 12 may 2025