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造山带挤出构造阐述了被边界断裂所围限的造山带深变质块体,在造山带内部垂向和(或)侧向应力的作用下折返变形的过程。研究主要集中在挤出块体的几何形态及其内部变形样式、边界断裂特征、挤出路径以及挤出动力来源等4个方面,其研究目的主要是为了解决造山带深变质岩石折返剥露的机制问题。依据挤出块体的挤出方向与造山带主体走向之间的关系,在三维球形坐标系Lx-Ly-Lz中,将造山带挤出构造大致分为7个端员类型(Ⅰ型～Ⅶ型)。其中Lx为造山带或俯冲带的主体走向;Ly呈水平方向并与Lx相垂直;Lz垂直于Lx和Ly所构成的平面。这些基本端员类型的组合及其之间的过渡类型可以详尽地诠释大别山印支期高压-超高压岩石的挤出过程。其中榴辉岩相挤出阶段介于Ⅳ型与Ⅶ型挤出构造之间,角闪岩相挤出阶段介于Ⅱ型与Ⅵ型挤出构造之间并可能具有渠道流挤出模式,而绿片岩相挤出阶段类似于Ⅴ型挤出构造。
The orogenic belt extrusion structure expounds the process of reentry deformation of the deep metamorphic blocks in the orogenic belt surrounded by the boundary faults under the vertical and / or lateral stress inside the orogenic belt. The research focuses on four aspects of the geometry of the extruded block and its internal deformation patterns, the boundary fracture characteristics, the extrusion path and the source of extrusion power. The main purpose of the study is to solve the problem of the reentry of deep metamorphic rocks in the orogenic belt Mechanism issues. According to the relationship between the extruding direction of extrusion block and the orogenic body, the three-dimensional spherical coordinate system Lx-Ly-Lz can be roughly divided into seven end-member types (Ⅰ-VII type). Lx is the main body of orogenic belt or subduction zone; Ly is horizontal and perpendicular to Lx; Lz is perpendicular to the plane formed by Lx and Ly. The combination of these basic endmember types and the transitional types between them can explain in detail the extrusion process of the Indosinian epithermal-ultrahigh-pressure rock in the Dabie Mountains. The eclogite facies extrusion stage is between type IV and type Ⅶ extrusion structures. The amphibolite facies extrusion stage is between type ¢ ò and ¢ õ extrusion structures and may have a channel extrusion pattern The greenschist facies extrusion stage is similar to the Ⅴ-type extrusion structure.