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在对东秦岭松树沟蛇绿岩的变质橄榄岩进行详细构造解析和显微构造研究的基础上，本文运用透射电子显微镜法着重对橄榄石位错构造进行了研究。结果表明，橄榄石主要位错类型为自由位错、位错壁和亚颗粒、位错弓弯和位错环等，它们是橄榄石在上地幔高温低应变速率条件下发生复杂蠕变的结果。统计自由位错平均密度约为２．５１×１０８ｃｍ－２，相应的流变差异应力为１５１．３ＭＰａ，流变速率为１．１７×１０－１５／ｓ，粘滞度为４．３１×１０２３Ｐａｓ；亚晶粒度平均约为１．６３６μｍ，相应的流变差异应力为１１３．０ＭＰａ，流变速率为１．３０７×１０－９／ｓ，粘滞度为２．８８×１０１７Ｐａｓ；动态重结晶平均粒度约为０．８９μｍ，相应的流变差异应力为１５．８ＭＰａ，流变速率为９．８９×１０－８／ｓ，粘滞度为５．３×１０１４Ｐａｓ．反映了松树沟蛇绿岩形成与演化过程中不同阶段的变形及其流变状态。
Based on the detailed structural analysis and microstructure study on the metamorphic peridotites of the Songshugou ophiolite in East Qinling, the dislocation structure of olivine has been studied by transmission electron microscopy. The results show that the main dislocation types of olivine are free dislocations, dislocation walls and subparticles, dislocation bow and dislocation loops, etc., which are the result of complex creep of olivine under high temperature and low strain rate in the upper mantle . The statistical average free dislocation density is about 2.51 × 108cm-2, the corresponding rheological differential stress is 151.3MPa, the rheological rate is 1.17 × 10-15 / s, the viscosity is 4.31 × 1023Pas ; The average grain size of subgrain is about 1.636μm, the corresponding rheological stress is 113.0MPa, the rheological rate is 1.307 × 10-9 / s, the viscosity is 2.88 × 1017Pas; dynamic recrystallization The average particle size was about 0.89μm, the corresponding rheological differential stress was 15.8MPa, the rheological rate was 9.89 × 10-8 / s and the viscosity was 5.3 × 1014Pas. It reflects the deformation and the rheological state in different stages of the formation and evolution of the Songshugou ophiolite.