We propose a geodynamic model for the Mediterranean area that requires mantle expansion growing eastward, above a relatively cold, chemical plume trapped in the Transition Zone (410-670 km) after that core/mantle perturbations released H, C, N, K, S long trapped within the D" layer. Lithosphere above the expanded asthenosphere underwent stretching and thinning and subordinate peripheral compression. Low-degree melting of the metasomatised asthenosphere produced ultra-alkaline magmas with a distinctive radiogenicity derived by the long term Rb/87Sr and U/Th decay leading to a unique isotopic end-member (ITEM, i.e. Italian Enriched Mantle).
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