Precambrian geodynamics(VI):Formation of North China Craton

The research on the North China Craton has made a series of great progress in recent 20 years,but it still has many un-resolved problems.Firstly,this paper discusses the existing problems in the Precambrian tectonic unit division of the North China Craton,and then proposes some principles of dynamic tectonic unit division,and preliminarily makes dynamic tectonic division of Paleoarchean-Mesoarchean, Neoarchean,Paleoproterozoic and Meso-Neoproterozoic tectonic units,respectively.Based on these tectonic divisions,this paper determines the different periods of unique deformation styles and tectonic evolution.According to the new tectonic divisions and a series of major Precambrian geological events recorded in the North China Craton,different stages of evolution of the unique structural styles and tectonic regimes and their transition are also discussed.This paper proposes the rigid cratonization of some Archean continental nuclei in the North China Craton occurred at about 2.5Ga,however,the obvious and earliest linear tectonic belts or rifts occurred at about 2.2 Ga.Therefore,this paper concludes the judgment of the Neoarchean initiation of plate tectonic regime in the North China Craton and provides the related structural evidences.Finally,based on our longterm structural analysis,this paper discusses the final assembly processes of the North China Craton in 1.85 Ga.