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国内外学者对大别—苏鲁区的超高压和高压变质带己进行了较深入的岩石学、同位素年代学及地球化学等领域的研究工作。相对而言,构造学研究比较薄弱。因而,所提出的超高压和高压变质岩石的形成及折返运动学模式,一般还缺乏坚实的构造学证据的支撑。我们通过关键地段详细构造分析及大比例尺(1∶10000)制图,结合区域上构造观察和可利用的已有岩石学、变质作用及同位素年代学资料,在判别早期碰撞或挤压组构与碰撞期后角闪岩相条件下伸展组构基础上,重点分析了超高压、高压变质岩石折返到中下地壳后形成的区域伸展构造框架。其构造样式类似于北美的科迪那拉型变质核杂岩,几何形态为穹窿型式,内部发育4个缓倾斜伸展拆离带,由下向上为下拆离带、中拆离带、上拆离带和顶拆离带,共同构成一个近平行的
Domestic and foreign scholars have carried out in-depth research in the fields of petrology, isotopic geochronology and geochemistry to the UHP and high-pressure metamorphic belt in Dabie-Sulu area. In contrast, the study of tectonics is relatively weak. Therefore, the proposed formation and re-kinetic models of ultrahigh-pressure and high-pressure metamorphic rocks generally lack solid tectonic evidence support. Based on detailed tectonic analysis and large-scale (1: 10000) mapping in key areas, combined with structural observations on the area and available petrology, metamorphism and isotopic chronological data, Based on the extensional structure of the amphibolite facies in the post-stage, the extensional tectonic framework formed after the UHP and high-pressure metamorphic rocks are folded back into the middle and lower crust is emphatically analyzed. Its structural style is similar to that of the Cordina type metamorphic core complex in North America. The geometric shape is a dome type. There are four gently inclined extension detachment belts in the interior, and the lower detachment belts are formed from bottom to top, The belt and roof detachment belt, together constitute a near parallel