Syn - collisional plutonic rocks aie composed of granodiorite and adamellite , which exposed al 由于极度艰苦的工作条件限制，本区研究程度极低。
2.
In terms of their geological and geochemical characteristics as well as the ages of these plutons , these three sub - belts from south to north are interpreted as syn - subductional , syn - collisional and post - collisional plutons respectively . composed of quartz diorite and quartz monzonite , the syn - subduction plutonic rocks are confined only to the south kunlun massif 俯冲期侵入岩仅出露于蛇绿岩带之南的昆南地块上，岩性组合为石英闪长岩-石英二长岩，三个主要岩体获锆石u - pb年龄值为481ma 、 461ma 、 452ma ，均为奥陶纪。
3.
Eight aspects related to the study of early precambrian metamorphic stratigraphy are dealt with in this paper : general situation of the study ; complexity of the stratigraphy and difficulties of the study ; thoughts and methods of the study ; division of rock suite , rock group and complex rock ; researches on important regional discordances ; types and characteristics of protolith and recovery of palaeoenvironment ; correct differentiation of the metamorphic strata , ttg rock system and other metamorphic plutonic rocks ; determination of the ages of the metamorphic strata 摘要主要论述了与早前寒武纪变质地层（学）有关的8个方面的问题：早前寒武纪变质地层的研究概况；早前寒武纪变质地层的复杂性和研究难度；早前寒武纪变质地层研究的思路和工作方法；早前寒武纪变质岩石地层单位岩群、岩组和杂岩的划分问题；重要区域性不整合的研究；鉴定变质地层的原岩类型、岩石性质和恢复古环境；正确区分变质地层和ttg岩系以及其他变质深成岩；变质地层时代的确定。
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