Discovery of a Hadean xenocrystic zircon in the Cathaysia Block

The early history of Earth is poorly understood,due to the lack of ancient rocks formed after the formation of the newborn Earth,especially for the first 500 million years(Hadean Eon).To our knowledge,this period is the most geodynamically vigorous in the crustal evolution history of Earth[1],and is characterized by intense collision with meteorites and the formation of a global magma ocean(～4.41 Ga;cf.review article by Ref.[2]).Therefore,ancient rocks formed in this period should provide essential evi-dence for the Hadean crustal evolution;however,most of the Hadean rocks were poorly preserved,caused by deuteric geological events[1].