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通过越南西北部Song Da带地层、构造、变质岩和岩浆岩的野外考察及补充填图,依据岩石组合特征和区域不整合,将Song Da带前新生代地层划分为前震旦纪结晶基底、寒武系-上三叠统下部及上三叠统上部-白垩系3个构造层。在对各构造层构造属性分析的基础上,与扬子-华南板块前新生代地层进行区域对比,结果显示,Song Da带前新生代各构造层与扬子-华南板块具有相似性,表明Song Da带属于扬子-华南板块。此外,对研究区各构造层形成的构造背景进行分析,认为它们分别是在Columbia超大陆的形成和Rodinia超大陆的裂解、稳定地台盖层的沉积、古特提斯洋关闭以及古太平洋板块向欧亚大陆边缘俯冲的背景下形成的。同时认为,Song Da带向海域的延伸部分——莺歌海盆地基底与Song Da带具有相同的前新生代基底构造层、构造属性和构造背景。
Based on the field investigation and supplementary mapping of stratigraphy, tectonism, metamorphic rocks and magmatic rocks in the Song Da belt in the northwestern Vietnam, the Song Da belt was divided into pre-Sinian crystalline basement and cold basement by the combination of rock features and regional unconformity Wu system - Lower Triassic and Upper Triassic - Cretaceous three structural layers. Based on the analysis of the tectonic structural attributes and regional comparison with the Pre-Cenozoic stratigraphy of the Yangtze-South China Plate, the results show that the structural zones of the Song Da belt are similar to the Yangtze-South China plate, indicating that the Song Da belt Belong to Yangtze - South China plate. In addition, the tectonic setting of the tectonic strata in the study area is analyzed. They are respectively the formation of the supercontinent in the Columbia and the cracking of the Rodinia supercontinent, the stable deposition of the platform cover, the closure of the ancient Tethys Ocean and the paleo-Pacific plate Formed against the backdrop of subduction of Eurasian margins. At the same time, it is considered that the extension of Song Da to the sea area - the Yinggehai Basin basement has the same pre-Cenozoic basement structural layer, structural property and tectonic setting as the Song Da belt.