RT Journal Article T1 Petrogenesis of Permian alkaline lamprophyres and diabasesfrom the Spanish Central System and their geodynamic contextwithin western Europe A1 Orejana García, David A1 Villaseca González, Carlos A1 Billstrom, Kjell A1 Paterson, Bruce A. AB Basic to ultrabasic alkaline lamprophyres anddiabases intruded within the Spanish Central System (SCS)during Upper Permian. Their high LREE, LILE and HFSEcontents, together with positive Nb–Ta anomalies, linktheir origin with the infiltration of sublithospheric K-richfluids. These alkaline dykes may be classified in two distinctgroups according to the Sr–Nd isotope ratios: (1) adepleted PREMA-like asthenospheric component, and (2) aBSE-like lithospheric component. A slight enrichment inradiogenic 207Pb and 208Pb allows the contribution of arecycled crustal or lithospheric component in the mantlesources. The intrusion of this alkaline magmatism is likelyto have occurred due to adiabatic decompression andmantle upwelling in the context of the widespread riftingdeveloped from Carboniferous to Permian in westernEurope. The clear differences in the geochemical affinity ofLower Permian basic magmas from north-western andsouth-western Europe might be interpreted in terms of amore extensive separation of both regions during thatperiod, until they were assembled during Upper Permian. PB Springer Science Business Media SN 0010-7999 YR 2008 FD 2008 LK https://hdl.handle.net/20.500.14352/49620 UL https://hdl.handle.net/20.500.14352/49620 LA eng NO The original publication is available at www.springerlink.com DS Docta Complutense RD 17 abr 2025