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7464801 
Journal Article 
THE JUMILLA LAMPROITE REVISITED - A PETROLOGICAL ODDITY 
Venturelli, G; Capedri, S; Barbieri, M; Toscani, L; Salviolimariani, E; Zerbi, M 
1991 
Yes 
European Journal of Mineralogy
ISSN: 0935-1221 
E SCHWEIZERBARTSCHE VERLAGSBUCHHANDLUNG 
STUTTGART 
3 
1 
123-145 
WOS:A1991EV42900010 
Among the Mediterranean lamproites, the Jumilla occurrence deserves particular interest since it contains significant amounts of carbonates and an apatite deposit. Jumillites (olivine-richterite madupitic lamproites) contain olivine (Mg# 89-93), phlogopite (Mg# 72-93), Fe-rich sanidine, spinels, K-rich richterite, clinopyroxene, fluorapatite and analcite (probably derived from leucite). Analcite can be locally very abundant (up to 40 % vol). The magmas were mostly peralkaline with high MgO (13-17 %), Cr (740-930 ppm), Ni (560-670 ppm), P2O5 (1.15-2.26 %), Ba, REE (Ce/Yb up to 160), Th (93-161) contents and high Sr-87/Sr-86 ratios (0.71378-0.71680). The rocks exhibit wide chemical variations which cannot be explained by fractional crystallization or by prograde partial melting of the same source. Carbonate-bearing assemblages are also present in the form of late crystallized aggregates in the groundmass (CARB-i) and as thin veins and infiltrates (CARB-ii) in the jumillite rocks. The carbonate assemblages and the jumillite magma are in some degree genetically related as suggested, for instance, by the Sr isotope data of the apatite. 
PETROLOGY; GEOCHEMISTRY; LAMPROITES; CARBONATES; SPAIN