Gelingyao high-Cr granite (Closepet-like) in Shangyi: New evidence of Late-Archean suture zone
尚义葛令夭高铬花岗岩(Closepet-like)——新太古代古缝合带的新证据

At northern of North China Craton, between Archean granulite nucleus and extra-continental sedimentary basin (hongqiyingzi Group), a Neoachaean ancient oceanic crust relict has been recognized (Wang et al., 2009). The low Al2O3 TTG rocks (2512±19Ma), the anatectic granites (Closepet-like) with rich K and high Cr (97×10-6~308×10-6), and quartz monzonites (Sanukitoid-like) with a large number of lamprophyre dykes have been discovered on both sides of the relict, they are closely related to subduction. The low Al2O3 TTG rocks were generated by partial melting of subducting slab under an amphibole-granulite subfacies condition. Anatectic granites were products of remelting of the TTG rocks and their basic development with increase in Cr were the results of complex mixed and metasomatism between mantle-derived magma and K-enriched anatectic granites.