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在伊尔岗地块东部,在已褶皱的以静力再结晶为主的区域里,整个绿岩带岩石的变质程度,是从葡萄石—绿纤石相至中等闪岩相,而在伴生花岗岩侵入体的强烈形变的动力变质区为中等闪岩相至闪岩麻粒岩的过渡相。与区域重力异常相符合的不同变质程度区的分布及分异的岩墙状超镁铁岩侵入体的出露层位证明,同时生成的绿岩带的变质程度明显地受所处构造体系的控制。在不同变质程度的变火山岩里残余岩相的性质表明较迅速地施加在前未变质岩序上的变质作用是非渐进型的。构造关系和有限的地质年令资料说明在26—27亿年间曾发生过一次范围很广的与老花岗岩基底再活动有关的变质幕,在此期间,太古代地壳中热力体系发生了明显变化。在伊尔岗地块东部与超镁铁岩石密切相关的硫化镍矿床有选择性地分布在深变质岩区。
In the eastern part of the Ergyang block, in the area where folds are mainly recrystallized, the metamorphic degree of the rocks in the whole greenstone zone ranges from gravel to greenstone to medium amphibolite facies. However, The strongly degenerated dynamic metamorphic zone of granite intrusions is the transitional phase between mid-amphibolite facies and amphibolite granulite. The distribution of different degrees of metamorphism consistent with regional gravity anomalies and the outcrops of differentiated diagenetic mafic intrusions show that the degree of metamorphism of the greenstone belts formed at the same time is obviously affected by the control. The properties of remnant facies in volcanic rocks of different metamorphism indicate that the metamorphism applied more rapidly to the former unmodified rocks is non-progressive. Tectonic relationships and limited geochronology indicate that a large range of metamorphic rocks associated with the reworking of the old granite had occurred during 26-27 billion years, during which time the thermodynamic system in the Archean crust had changed significantly. Nickel sulfide deposits, which are closely related to ultramafic rocks in the eastern part of Ilgyang block, are selectively distributed in the deep metamorphic rock area.