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大别山东部双河附近面理化榴辉岩中， 所有榴辉岩相矿物包括石榴石、绿辉石乃至金红石都受到强烈拉伸。用透射电镜可以观察到石榴石晶体中塑性变形的显微构造， 包括自由位错、位错环、位错壁和位错网。拉伸石榴石的应变轴比表现为 Ｘ＞ Ｙ＞ Ｚ。运动学标志如石榴石的不对称碎斑和旋转的金红石颗粒， 表明有旋转应变的作用。石榴石和金红石的福林系数分别为１１８ 和０９８。所有这些都表明石榴石是在接近于平面应变的条件下形成。由于石榴石颗粒在应变前后体积未变，因此也是在简单剪切作用条件下形成的。根据石榴石韧性变形要求的温度条件， 此种变形应在榴辉岩相条件下发生， 代表一次向南的逆冲作用， 经过展开后， 逆冲的方向为南西。根据石榴石的流变律， 其韧性变形的最低温度估计约为 ８００℃。石榴石中普遍有一组透入性破劈理， 它产生于面理化榴辉石折返后的角闪岩相早期， 形成于石榴石韧性变形之后。破劈理及其中反Ｓ形破劈理的运动指向表明有向北的滑动， 发生在主簿源复背斜形成之前； 主簿源复背斜使面理化榴辉岩的产状由倾向北改变为倾向南。根据面理化榴辉岩及其围岩的同位素年龄， 估算出面理化榴辉岩在２００～１９０ Ｍａ 期间的平均垂直折返速率为９ｍ ｍ ／ａ。此外， 还
In the physicochemical eclogites near the Shuanghe River in the eastern part of the Dabie Mountains, all eclogitic facies minerals, including garnet, omphacite, and even rutile, are strongly stretched. The microstructures of plastic deformation in garnet crystals were observed by TEM, including free dislocations, dislocation loops, dislocation walls and dislocation networks. The strain axis ratio of stretched garnet is expressed as X> Y> Z. Kinematic signs such as garnet asymmetric crush and rotating rutile particles, indicating the role of rotational strain. The Forint coefficients for garnet and rutile are 118 and 098, respectively. All of this shows that garnets are formed near planar strain. Since garnet particles have not changed in volume before and after strain, they are also formed under simple shear conditions. According to the deformation temperature requirements of garnet toughness deformation, such deformation should occur under eclogite facies, representing a southward thrusting effect. After unfolding, the thrusting direction is southwest. According to the law of garnet flow, the minimum temperature of ductile deformation is estimated to be about 800 ° C. Garnet generally has a group of penetrating broken cleavage, which arises in the early period of amphibolite facies eclogite after the reunification, formed after the ductile deformation of garnet. Broken cleavage and the anti-S-shaped cleavage movement indicate that there is a northward slippage occurred before the formation of the main book source complex anticlines; the main book source complex anticlines make the occurrence of the physicochemical eclogites from north to south Change to the south. Based on the isotopic ages of the physicochemical eclogites and their surrounding rocks, it is estimated that the average vertical reentry rate of the geochemical eclogites during the period of 200-190 Ma is 9 m m / a. Also, yet