Abstract Based on geological study and integrated analysis of the 1:1,000,000 gravity and magnetic anomaly map for the northern margin of the North China platform, we hold that the northern margin of the North China platform is composed of three Archeozoic landmasses, i. e. Dongsheng, Chifeng and Liao-dong. Along the border areas of the three landmasses and near the deep fault zones within these landmasses there occur Late Archeozoic greenstone belts, suggesting that these three landmasses might have been linked with each other in Late Archeozoic-Early Proterozoic period (some 2500 Ma). Amarginal uplifted zone exists in the northern part of each landmass, but the discontinuity of the gravity and magnetic anomalous fields suggests the difference in the basement evolutionary history of these landmasses. Acomparison of orientations of fault zones inferred on the basis of gravity and magnetic anomalous fields in these three landmasses indicates that the relative movement between these landmasses must have proceeded along these deep fault zones.
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