Felsic continental crust is unique to the Earth in the solar system, but it still remains controversial regarding its formation, accretion and reworking. The plate tectonics theory has been significantly challenged in explaining the origin of continents as Archean continents rarely preserve hallmarks of plate tectonics. In contrast, growing evidence emerges to support mantle plume-derived oceanic plateau models as the models can reasonably explain the origin of bimodal volcanic assemblages and nearly coeval emplacement of tonalite-trondjhemite-granodiorite (TTG) rocks, presence of ~1600ºC komatiites and dominant dome structures, and lack of ultra-high-pressure rocks, paired metamorphic belts and ophiolites in Archean continents. Although plate tectonics seems to fail in explaining the origin of continents, it has been successfully applied to interpret the accretion or outgrowth of continents along subduction zones where new mafic crust is generated at the base of continental crust through partial melting of the mantle wedge with addition of H2O-dominant fluids from the subducted oceanic slabs, and partial melting of the juvenile mafic crust results in the formation of new felsic continental crust, leading to the outside accretion of continents. Subduction processes also cause the softening, thinning and recycling of continental lithosphere due to the vigorous infiltration of volatile-rich fluids and melts especially along weak layers or weak belts, leading to the widespread reworking and even destruction of continental lithosphere. Reworking of continents also occurs in continental interiors due to plume-lithosphere interactions, which, however, leads to much less degrees of lithospheric modification than subduction-induced craton destruction.

Oxygen fugacity controls the behavior of multivalent elements and compositions of C-O-H fluids in Earth’s mantle, which further affects the cycling of materials between the deep interior and surface of Earth. The redox state of mantle lithosphere of typical stable cratons has been well documented, but how oxygen fugacity had varied during craton destruction remains unclear. This study estimates the oxygen fugacity of peridotite xenoliths entrained in Mesozoic and Cenozoic basalts on North China Craton (NCC), a typical destroyed craton. The results reveal that the mantle lithosphere beneath the NCC experienced three stages of evolution in terms of oxygen fugacity. First, the refractory and oxidized peridotite xenoliths indicate the lithospheric mantle experienced a high degree of melt extraction and later long-term and complicated metasomatism before craton destruction. Then, the variations of olivine Mg-number in peridotites and oxygen fugacity reveal significant metasomatism by melts originated from the shallow asthenosphere during the destruction of the NCC since the Mesozoic. The third stage may have occurred when mantle peridotites interacted with silica-undersaturated melts stemmed from the mantle transition zone where the stagnant Pacific slab underlies. This study further verifies that the asthenospheric convection induced by the roll-back of the subducted paleo-Pacific slab played a crucial role in the destruction of the NCC and helps understand the oxygen fugacity variability during the later life of the craton.