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阿迪龙达克(Adirondacks)南部的多期变形变质岩呈明显的线状组构,它由平行于早期褶皱轴而且位于叶理面内的扁平条带构成。这些条带常常是单矿物,由石英、长石和镁铁质矿物组成。显然,从最弱到最强变形的岩石转变中,这些条带可能是随着区域旋转应变作用而使晶粒或集合体拉长的结果,同时,旋转应变也使早期的褶皱轴发生旋转,以至平行于线理。长石尾状物对于叶理的一致不对称性表明,简单剪切是应变的主要方式。所以认为,条带的长度标明有限应变椭球体的最大延伸方向(X)。
The multistage metamorphic rocks in the southern Adirondacks show a conspicuous linear structure consisting of flat bands parallel to the early fold axis and located within the leaf surface. These bands are often single minerals, consisting of quartz, feldspar and mafic minerals. Obviously, from the weakest to the most strongly deformed rocks, these bands may be the result of lengthening the grains or aggregates as the region rotates and the rotation strain also causes the early fold axis to rotate, Even parallel to the line. The consistent asymmetry of the feldspars for the foliage suggests that simple shearing is the primary mode of strain. Therefore, it is considered that the length of the band indicates the maximum extension direction (X) of the finite strain ellipsoid.