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1994年完成的大别造山带深地震测深剖面(全长420km)穿越了华北地块,大别造山带和扬子地块三个构造单元.获得了垂向成层、横向分块的地壳纵、横波速度结构.结合地质、地球化学研究成果,大别山地壳可分为三层:上地壳是多重叠覆的构造岩石层,中地壳为韧性变形层,下地壳整体成分偏酸性.大别山地表及浅部的超高压变质岩石具有典型的薄皮构造特征.本文提出大别山不同期双向俯冲造山模式和超高压变质岩石的反向加楔退拔折返机制;大别山腹地至今仍保留6-8km厚的山根.
The deep seismic sounding profile of the Dabie orogenic belt completed in 1994 (420km in total length) traverses the three tectonic units of the North China block, the Dabie orogenic belt and the Yangtze block. Vertical and transverse crustal crustal and shear-wave velocity structures are obtained. According to the geological and geochemical research results, the Dabie Mountain crust can be divided into three layers: the upper crust is a multi-superimposed tectonic rock layer, the middle crust is a ductile deformation layer, and the overall composition of the lower crust is acidic. The ultrahigh-pressure metamorphic rocks on the surface and in the shallow part of the Dabie Mountain have typical thin-skin structure features. In this paper, the reversal wedgeback mechanism of the UHP metamorphic rocks in different stages of the Dabieshan syncline and the retrograde wedgeback mechanism are proposed. In the hinterland of the Dabie Mountains, there are still 6-8 km thick roots.