Figure 6. Relationship between MgO and FeO+Fe2O3 in rocks from various regions: (1) - Iceland; (2) - Lesser Caucasus; (3) - Kurile Islands; (4) - Tien Shan; (5) - Cape Verde fault; (6) - Kamchatka; (7) - Trans-Baikal region; (8) - xenoliths from Yakutia kimberlite pipes; (9) - magnetic xenoliths of Yakutia (Js>1 A m2/kg); (10) - Aldan shield; (11) - Voronezh crystalline massif. The broken lines delineate tentative areas of the accumulative trend (vertical area) and differentiation trend (horizontal area).