Geologic and structural records in Early Precambrian and features of long wave(>120 km) aeromagnetic anomaly indicated that southern Tarim, Central North China and northern Korean(Rangrim terrain) had similar Archean crystalline basements, and probably had been parts of a united Archean craton in NW-SE stretching. Medium wave(20～120 km) aeromagnetic anomaly demonstrated a series of NEE-NNE striking linear aeromagnetic anomalies, which reconstructed the Archean high-graded crystalline basement. Results of geologic and structural investigations showed that they were responding to crust-scale long live faults individually. Along them, large-scale left-lateral transtensional ductile shearing had occurred during Paleoproterozoic period. Series insialic mobile belts formed when the southern Tarim, and the northern Korean continental blocks were detached to SW and NE separately from Central North China block. According to the roles of the ductile transtensional shear zones in the reconstruction process of the Archean craton, we divided them into three independent shear systems as western system between southern Tarim and Central Northern China blocks, eastern system between Central Northern China and Rangrim blocks, and Qinglong-Taihangshan-Zhongtiaoshan system in the inner part of the Central Northern China block. The western system was composed by Altyn, Datong-Huanxian shear belts and secondary Langshan-Jilantai and Yabulaishan shear belts between them, controlling the sedimentary and structural evolution of the Paleoproterozoic Alaxa group and the upper Jining Group characterized as khondalite suites. The eastern system included the Yishui, Xinbing-Huadian and the other ductile shear belts, and the related mobile belts presented as Fenzishan Group and Jinshan Group in Jiaodong region, and the Liaohe Group in Liaoning-Jilin region. The Qinglong-Taihangshan-Zhongtiaoshan system appeared as amphibolite-phased mylonitic gneiss and augen mylonites as a result of reworked Fuping and Zanhuang Archaen gneisses in Taihangshan area. Typical b-type lineations, developed in the mylonites, indicated sub-horizontal or low angle left-lateral ductile shearing. The related Paleoproterozoic mobile belts were represented by Shuangshanzi-Qinglonghe, Wutai-Futuo, Gantaohe-Dongjiao, Lüliang and Jining belts composed mainly of sedimentary and volcanics in different scales, and did not join each other in space. Magnetic susceptibility of these formations was obviously lower than the Archean high-graded metamorphic crystalline basements, while the responding ductile shear zones created enhanced anisotropy magnetic susceptibility attributed to their penetrative mineral lineations, both of them contributed to the crustal scale NEE-NNE striking linear aeromagnetic anomalies. The insialic mobile belts mentioned above were folded and inverted during the Zhongtiao movement at the end of the Paleoproterozoic, meanwhile southern Tarim, Central North China and northern Korean Archean blocks joined again to form a latitudinal stretching central continent which were gradually stabilized. The crust-scale transtensional ductile shear belts were mostly traced by later brittle faults in different natures during the geological history after Mesoproterozoic.
Zhang Jiasheng,Li Yan,Huang Xiongnan. PALEOPROTEROZOIC CRUST-SCALE TRANSTENSIONAL SHEAR,DETACHMENT AND INSIALIC MOBILE BELTS IN NORTH CHINA:GEOLOGIC AND TECTONIC IMPLICATIONS FOR THE NE-STRIKING LINEAR AEROMAGNETIC ANOMALY[J]. Chinese Journal of Geology, 2007, (2): 267-302.