Complex growth and reworking processes in the Yangtze cratonic nucleus

摘要: Abstract The Kongling Complex (KC), including the northern (NKC) and southern parts (SKC), represents a rare relic of Archean crust in Yangtze Craton, an ideal target to investigate Precambrian evolution continental crust. In SKC, history Archean-Paleoproterozoic growth reworking has not yet been clearly understood. New geochemical geochronological data on basement rocks (i.e., gneiss, migmatite, amphibolites) their overlying metasediments combined with published results from NKC, allow further subdivision into western, middle eastern zones, which proven useful understanding cratonic nucleus. U-Pb dating Lu-Hf isotopes zircons biotite gneisses (with or without amplibole) amphibolites suggest that SKC experienced crustal re-melting (reworking) event at ∼2.9 Ga, accretion/reworking at ∼2.7 Ga, later at ∼1.73 Ga and ∼0.8 Ga. These records are partly consistent what is known about NKC. main differences between them ages > 3.0 Ga 2.1–2.0 Ga only found NKC but SKC. Hence, copy According rock assemblages ages, may have affinity western zone That also supported by geophysical presence fossil Huangling magma chamber beneath at 10–20 km depth ( Mei et al., 2013 ). Therefore, our provide new Complex: stayed together part Mesoarchean Neoproterozoic (2.9–0.8 Ga) time, they were separated intrusion magmas at ∼0.8 Ga.