PETROGENESIS AND CONDITIONS OF CRYSTALLIZATION OF SPANISH LAMPROITIC ROCKS.

Abstract

The lamproitic rocks of southeast Spain (8. 6-6 Ma) occur mainly as dykes and plugs in the provinces of Murcia, Almeria and Albacete. Phlogopite, olivine, apatite, spinel, sanidine and glass are ubiquitous. Clinopyroxene, orthopyproxene, K-rich amphibole, biotite, ilmenite, pseudobrookite, leucite, analcime and carbonates may be additional phases. The magmas crystallized at temperatures below ca. 1200 degree C. The distribution of the high-valency ( greater than 3) elements was largely influenced by the heterogeneous distribution of accessory phases in the source and by the melt structure. The magmas were generated from an enriched mantle source containing phlogopite, orthopyroxene, olivine and accessory plates (e. g. , apatite). Show more