Geological and isotopic geochemical constraints on the evolution of the Fuping Complex, North China Craton

The Neoarchean to Paleoproterozoic Fuping Complex together with the adjacent Hengshan and Wutaishan complexes form the middle part of the Central Zone that separates the North China Craton into the Eastern and Western Archean continental blocks. The Fuping Complex comprises three major lithological assemblages: the similar to 2.50 Ga Fuping trondhjemite-tonalite-granodiorite (TTG) gneisses, the Wanzi paragneisses, and the 2.08 and 2.02 Ga Nanying granitic gneisses. The TTG gneisses contain abundant enclaves of highly-metamorphosed supracrustal rocks, including similar to 2.70 Ga mafic granulites and amphibolites with e(Nd)' of + 3.29 to + 3.96 and T-DM of 2.72-2.82 Ga, and are characterized by T-DM of 2.76-3.04 Ga and a linear correlation between 6(Nd)' (- 1.64 to + 0.96) and 1/Nd, indicative of mixing of melts derived from the similar to 2.70 Ga metabasic rocks and similar to 3.0 Ga crustal materials. Mafic dikes along the Chengnanzhuang shear zone were most likely emplaced at similar to 2.31 Ga and have e(Nd)(t) of + 2.24 to + 4.78 and T-DM of 2.34-2.59 Ga. The Nanying granitic gneisses with E-Nd(t) of - 4.04 to - 5.24 were most likely related to partial melting of the similar to 2.70 Ga supracrustal rocks and/or the - 2.50 Ga TTG gneisses. These geological relationships and isotopic data suggest that the Fuping Complex probably formed from the following live major tectonomagmatic events: (1) mafic, magmatism and early crustal growth at similar to 2.7 Ga, with the possible existence of older ( - 3.0 Ga) crust(s); (2) collision-related crustal thickening, underplating of basaltic magma, high-grade metamorphism, crustal anatexis and TTG magmatism at similar to 2.5 Ga; (3) extensional deformation and emplacement of the mafic dikes and the Nanying granitic plutons along the Chengnanzhuang shear zone ( similar to 2.5 to similar to 2.0 Ga); (4) S-type granitic magmatism and associated amphibolite-facies metamorphism ( similar to 2.0 to similar to 1.80 Ga); and (5) emplacement of granitic pegmatite dikes at similar to 1.80 Ga. (C) 2002 Elsevier Science B.V. All rights reserved.