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THERMOCALC (tcds62cid; Holland and Powell 2011). Significant results were obtained only with the 5.5 data- base applied to sample 117,350. 5 . Resu l ts 5.1. Whole-rock geochemistry 5.1.1. Major and trace element composition The composition of the mafic rocks is characterized by SiO 2 contents in the range 45.32–50.13% (average 47.85), moderate Na 2 O content (average 2.00) and low K 2 O content (average 0.46), variable TiO 2 content (0.27– 1.53; average 0.69), high contents in MgO (7.65–12.09; average 9.72), moderate MgO/MgO+FeO ratios in the range 0.40–0.66 and variable FeO(t)/MgO ratios in the range 0.51–1.51. The LOI content is moderate (1.38– 2.98). These mafic rocks show variable contents in some HFSE: Nb (<0.2–5.1 ppm), Zr (9–88 ppm), Th (<0.05–2.58), Hf (0.3–2.2), and Ta (0.01–0.29). Some sam- ples show a high depletion in these elements, while another group of samples shows moderate content Figure 4. X-Ray maps obtained from sample 117,350. a) Phase map showing the textural distribution of the mineral phases. b), c), d) Compositional zoning in garnet for Ca, Fe and Mn, respectively. Images have been treated with Imager software (Torres-Roldán and García-Casco 2003) and consist of the XR signals of the elements (colour-coded, expressed in counts) in the mineral(s) of interest (with polished defects, voids and all other minerals masked out), set on top of a grey-scale base layer that contains the basic textural information of the scanned areas (see additional explanations in the text). 10 R. ARENAS ET AL. &KDSWHU