东秦岭松树沟蛇绿橄榄岩结构构造及其组构特征

Structure-texture and Fabric Features of Peridotites in Songshugou Ophiolite, Eastern Qinling

东秦岭松树沟蛇绿岩的橄榄岩结构构造及组构研究表明，该蛇绿橄榄岩主要经历了３期塑性变形的叠加改造，分别为洋盆扩张阶段以动态重结晶作用为主要特征的塑性变形、蛇绿橄榄岩块底辟侵位于上覆玄武岩过程中的高温塑性变形和蛇绿岩构造侵位过程中的低温塑性变形，反映了其特征的构造演化过程。

Based on the structural analysis of deformed peridotites in Songshugou ophiolite, the mantle ductile shear zone was discovered, which was superimposed by ductile-brittle and brittle deformations. The structure-texture and fabric features suggest that the ophiolitic peridotites evolved through three phases of plastic deformations. First, the olivines were deformed during the ocean extended, and the dynamic recrystallization is the main mechanism of the plastic deformation. Second, high temperature fabric was formed during the peridotites diapiric emplaced into the overlying basalts. Third, low temperature fabric was formed during the tectonic emplacment of Songshugou ophiolite.