The main old lands in China and assembly of Chinese unified continent  

作　　者：ZHAI MingGuo 

机构地区：[1]Key Laboratory of Mineral Resources,Chinese Academy of Sciences [2]State Key Laboratory of Lithosphere Evolution, Institute of Geology and Geophysics, CAS

出　　处：《Science China Earth Sciences》2013年第11期1829-1852,共24页中国科学（地球科学英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.2012CB4166006);the National Natural Science Foundation of China(Grant Nos.41030316 and 41210003)

摘　　要：The main old lands in China include the North China Block(NCB),South China Block(SCB)and Tarim Block(TRB),all of which have individual tectonic evolving histories.The NCB experienced complex geological evolution since the early Precambrian onwards,and carries important records from the old continental nuclei,giant crustal growth episode and cratonization(stabilitization),then to the Paleoproterozoic rifting-subduction-accretion-collision with imprints of the Great Oxygen Event(GOE),and to the Late Paleoproterozoic-Neoproterozoic multi-stage rifting representing North China platform tectonic features.The TRB has two-layer basement of the Early Precambrian metamorphic complexes and Neoproterozoic sedimentary sequences.Three till sheets have been reported.The SCB consists of the Yangtze Block(YZB)and Cathaysia Block(CTB)that were cohered in the Neoproterozoic.The YZB recorded tectonic processes of the Early Precambrian crustal growth,1.0–0.9 Ga and 0.8–0.6 Ga metamorphic-magmatic events,and two Neoproterozoic glaciations.The CTB consists of ca.1.8Ga,1.0 to 0.9 Ga and ca.0.8 Ga granitic gneisses and metamorphic rocks,indicating there was a vast Precambrian basement.The Neoproterozoic sedimentary rocks overlie partly on the basement.That the YZB and CTB have a Neoproterozoic uniform cover layer illustrates the SCB should form,at least,during 1.0–0.9 Ga,corresponding to the Rodinia Supercontinent.The Central Chinese Orogenic System with high-ultra-high-pressure metamorphic rocks supports a suggestion that the abovementioned three old lands were collided to assemble a unified Chinese Continent during the Pangea orogenic period.The main old lands in China include the North China Block （NCB）, South China Block （SCB） and Tarim Block （TRB）, all of which have individual tectonic evolving histories. The NCB experienced complex geological evolution since the early Pre- cambrian onwards, and carries important records from the old continental nuclei, giant crustal growth episode and cratoniza- tion （stabilitization）, then to the Paleoproterozoic rifting-subduction-accretion-collision with imprints of the Great Oxygen Event （GOE）, and to the Late Paleoproterozoic-Neoproterozoic multi-stage rifting representing North China platform tectonic features. The TRB has two-layer basement of the Early Precambrian metamorphic complexes and Neoproterozoic sedimentary sequences. Three till sheets have been reported. The SCB consists of the Yangtze Block （YZB） and Cathaysia Block （CTB） that were cohered in the Neoproterozoic. The YZB recorded tectonic processes of the Early Precambrian crustal growth, 1.0~0.9 Ga and 0.8-0.6 Ga metamorphic-magmatic events, and two Neoproterozoic glaciations. The CTB consists of ca. 1.8 Ga, 1.0 to 0.9 Ga and ca. 0.8 Ga granitic gneisses and metamorphic rocks, indicating there was a vast Precambrian basement. The Neoproterozoic sedimentary rocks overlie partly on the basement. That the YZB and CTB have a Neoproterozoic uniform cover layer illustrates the SCB should form, at least, during 1.0-0.9 Ga, corresponding to the Rodinia Supercontinent. The Central Chinese Orogenic System with high-ultra-high-pressure metamorphic rocks supports a suggestion that the above- mentioned three old lands were collided to assemble a unified Chinese Continent during the Pangea orogenic period.

关 键 词：main old lands geological characteristics unified continent China 

分 类 号：P531[天文地球—古生物学与地层学]