The Discovery and Geochemical Characteristics of an Eocene Peridotite Xenolith-Bearing Mafic Volcanic Neck in Coastal Southeast China

The mantle beneath coastal SE China evolved from enriched to depleted between the Cretaceous and Neogene, although precise timing of this change remains unclear. Here, we focus on a newly discovered Eocene mafic volcanic neck that contains peridotite xenoliths in Fuding area Fujian Province, present new whole-rock Ar–Ar data which indicate flood basalts formed during (ages 38.5 ± 1.2 42.3 2 Ma). basalt, gabbro, diabase are geochemically similar ocean island basalt (OIB) have Sr I values range 0.703794 0.703911 (average 0.703865) εNd(t) 3.05 4.56 3.90). These samples yield two-stage Nd model (T DM2 ) ages 0.61–0.73 Ga 0.67 Ga). all these units magmas derived an OIB-type source, with both gabbro recording minor amounts crustal contamination. Its OIB type geochemical characteristics may be inherited materials characteristics. Peridotite within provide evidence nature area, especially post late-Mesozoic evolution China. occurring Eocene.