Slab-melting during Alpine orogeny: evidence from mafic cumulates of the Adamello batholith (central Alps, Italy).

The Adamello batholith is the major Tertiary calc-alkaline intrusion of the Italian Alps. It consists primarily of tonalites to granodiorites and locally contains bodies of amphibole-rich mafic to ultramafic cumulates (hornblendites to amphibole gabbros). In these cumulates, two different parageneses of igneous origin can be distinguished. The first consists of euhedral brown amphibole with olivine, spinel and clinopyroxene inclusions. The second paragenesis consists of poikilitic plagioclase containing fine-grained euhedral clinopyroxene, minor green amphibole and accessory titanite, calcite, quartz, zircon, apatite and Fe–Ti-oxide phases.