Mafic and ultramafic enclaves in Ustica Island lavas: Inferences on composition of lower crust and deep magmatic processes

Density measurements pointed out higher values for clinopyroxenites (3160 to 3300 kg/m3) than for gabbros (ca. 2900 kg/m3). Given the density contrast between enclaves and host lavas (2790 kg/m3) and assuming appropriate rheological models, we calculated a minimum ascent rate of 0.01 m/s, corresponding to an ascent time in the range of 5-29 days for a depth of entrapment of 25 km.