Genesis of arc magmas: how many primary magmas exist in an arc volcano?

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We recovered and studied primitive basalt lavas from Pagan Volcano, Mariana Oceanic arc, and our findings have been attributed to each of the three parts of the subduction factory, which we describe as Mission Immiscible, Mission Invisible and Mission Inevitable, respectively. Mission Immiscible involves the subduction components, derived from the subducting slab below the volcanic front at the depth of 100 km, which consist of hydrous carbonate melt (carbonatite) and silicate melt (sediment melt). Mission Invisible involves the highly depleted residual mantle wedge of the subduction zone, composed of phlogopite-bearing dunite and harzburgite, which depletes Nb, Ta, Zr and Hf, and fractionates Nb from Ta, and Zr from Hf in arc magmas. Mission Inevitable describes the assimilation of arc magmas when they evolve; inevitable even in an oceanic arc.