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长乐 -南澳断裂带是东南沿海地区陆内强烈变质 -变形带。带内沉积岩、火山岩和早白垩世的钙碱性角闪石黑云花岗岩和花岗闪长岩都已发生可达角闪岩相的变质和石英 -长石相韧性剪切变形。鉴于高温矿物和强烈韧性变形多出现在深成岩附近 ;远离深成岩 ,变质和变形就逐渐减弱 ,故本文认为 ,至少有一部分变质变形的热源是由岩浆提供的。韧剪组构和糜棱质花岗岩是在岩浆侵位的晚期或长乐 -南澳断裂带左旋走滑时 ,在中地壳部位同时形成的 ,长乐断裂带中花岗岩的组构记录了一期同走滑变形的岩浆作用 ,“软变形”作用。据此 ,长乐 -南澳带内花岗岩的形成是受走滑剪切应力和岩浆热双重制约的 ,是在走滑过程中实现的。其动力来源可能与晚中生代的太平洋板块沿日本中央构造线—台湾纵谷带朝东亚陆缘的斜向俯冲有关。
The Changle-Nan’ao fault zone is a strongly metamorphic-deformation zone in the southeastern coastal area. Both metamorphic and quartz-feldspars ductile shear deformation of up to amphibolite facies have occurred in the calc-alkaline hornblende biotite and granodiorite in the sedimentary, volcanic and Early Cretaceous. In view of the fact that high-temperature minerals and strong ductile deformation occur near deep plutons, the metamorphism and deformation will gradually weaken away from the deep plutons, so this paper argues that at least part of the heat source for the metamorphism is provided by magma. The ductile-shear structure and mylonitic granites were formed in the middle crust at the same time as the late magmatic emplacement or the left-lateral strike-slip of the Changle-Nan’ao fault zone. The structure of the granites in the Changle fault zone recorded a period of syn- Deformation magma, “soft deformation” effect. Therefore, the formation of Changle-Nan’ao intragranular granite is controlled by both the strike-slip shear stress and magmatic heat and is achieved during the strike-slip process. The power source may be related to the oblique subduction of the Late Mesozoic Pacific plate along the central tectonic line of Japan - the longitudinal direction of the Taiwan Rift to the East Asian continental margin.