The extremely enriched mantle beneath the Yangtze Craton in the Neoproterozoic: Constraints from the Qichun pyroxenite

•The emplacement age of the Qichun pyroxenites is 808±4Ma.•Their extremely negative zircon ɛHf(t) values indicate an enriched SCLM source.•This mantle source was formed by reaction between the mantle and ancient sediment.•The Neoproterozoic SCLM beneath northern Yangtze Craton varied from depleted to enriched.