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对扬子板块中部湖北三峡早三叠世大冶组灰岩做了古地磁研究。特征剩磁数据通过了一致性检验、倒转检验。主成分分析（PCA）分离出二组剩磁组分,一组为特征剩磁,另一组系印支期重磁化。岩石磁学研究表明携磁矿物为碎屑磁铁矿,数据表明,结合扬子板块三叠纪古地磁研究的新成果,得到扬子板块三叠世的古地磁平均极为:30.3°N,198.4°E,α_(95)= 9.2°。从已有的三叠纪古地磁数据表明,扬子板块中部具有明显的局部区域性旋转,导致磁偏角与褶皱轴向趋于一致,与华南三叠纪古地磁数据比较及地质证据2个方面,认为印支期华南地块与扬子板块拼合可能西部早于东部。
Paleomagnetism was studied on the limestone of the Daye Formation of the Early Triassic in the Three Gorges, Hubei Province, central China. Characteristics of residual magnetic data through the consistency test, inverted test. The principal component analysis (PCA) separates two groups of remanence components, one of which is characterized by residual magnetism and the other of which is Indosinian re-magnetization. The rock magnetism study shows that the magnetotelluric minerals are clastic magnetites. The data show that with the new results of Triassic paleomagnetism research in the Yangtze Plate, the Paleogene paleo-geomagnetic anomalies in the Yangtze Plate are extremely high: 30.3 ° N and 198.4 ° E , α_ (95) = 9.2 °. From the existing Triassic paleomagnetic data, it is shown that there are obvious local regional rotation in the middle part of the Yangtze plate, which leads to the tendency that the declination angle and the fold axis converge. Compared with the Triassic paleomagnetic data in South China and two geological evidences , That Indo-Chinese South China block and the Yangtze plate mosaic may be earlier than the east west.