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在山东半岛东南端的乳山海阳所,角闪岩和长英质片麻岩呈互层产出。在某些角闪岩层的中心残留有弱变形的麻粒岩和强变形的过渡榴辉岩(斜长石榴辉岩)团块。在弱变形的麻粒岩团块中发育有窄的(<1cm)剪切条带。沿着这些剪切条带和在强变形过渡榴辉岩团块中,原麻粒岩被转化为含斜长石的过渡榴辉岩。变形和流体在这一转化过程中加速了元素扩散和迁移的速度,在变形强和有流体加入的部位麻粒岩向榴辉岩转化的程度明显增强。麻粒岩相矿物组合(Cpx-Ⅰ+Opx+Pl-Ⅰ+Hbl-Ⅰ+Grt-Ⅰ+Ilm)及其花岗变晶结构被完好地保存于弱变形的麻粒岩中,其矿物成分显示出0.8~0.9GPa和780℃~830℃的麻粒岩相变质条件。榴辉岩相叠加在麻粒岩中形成了一系列的环边状矿物和结构:环边状石榴石(Grt-Ⅱ)形成于麻粒岩相斜长石(Pl-Ⅰ)和暗色矿物(如Cpx-Ⅰ、Opx和Hbl-Ⅰ)的交界处,细粒石榴石(Grt-Ⅱ)、富钠单斜辉石(Cpx-Ⅱ)和石英形成于麻粒岩相角闪石(Hbl-Ⅰ)的外缘。同时榴辉岩相叠加造成麻粒岩相单斜辉石边缘钙契尔马克组份的降低和硬玉组份的升高。但在弱变形的麻粒岩中,麻粒岩相单斜辉石(Cpx-Ⅰ)的外缘并无榴辉岩相单斜辉石?
At the Rushan Haiyang Institute at the southeastern tip of Shandong Peninsula, amphibolite and feldspathic gneiss are interbedded with each other. In some amphibolite strata, weakly deformed granulites and strongly deformed transitional eclogites (plagioclase eclogites) remain in the center. Narrow (<1 cm) shear bands develop in the weakly deformed granulite clumps. Along these shear strata and in the strongly deformed eclogite mass, the primary granulites are converted to plagioclase-bearing transitional eclogites. Deformation and fluid accelerated the rate of element diffusion and migration during this transformation. The degree of conversion of granulite to eclogite was significantly enhanced in the areas where deformation and fluid addition occurred. The granulite facies assemblage (Cpx-Ⅰ + Opx + Pl-Ⅰ + Hbl-Ⅰ + Grt-Ⅰ + Ilm) and its granitic crystal structure are well preserved in weakly deformed granulites with mineral compositions of 0.8-0.9 GPa and Granulite facies metamorphism from 780 ℃ to 830 ℃. The eclogite superimposed on granulite formed a series of ring-shaped minerals and structures: the ring-shaped garnet (Grt-Ⅱ) formed on granulite facies plagioclase (Pl-Ⅰ) and dark mineral Such as Cpx-Ⅰ, Opx and Hbl-Ⅰ, Grec-Ⅱ, Cpx-Ⅱ and quartz were formed on the boundary of Hbl- I) of the outer edge. At the same time, the superimposition of eclogite facies resulted in the decrease of the Caqehlicer component and the increase of jadeite components in the granulite facies clinopyroxene. However, in weakly deformed granulites, there is no eclogite-clinopyroxene on the outer edge of the granulite-clinopyroxene (Cpx-Ⅰ).