古吉黑造山带的演化与陆壳的增生  

The evolution of the paleo Jihei orogenic belt and accretion of the continental crust

作　　者：彭玉鲸[1] 赵成弼[1] 

机构地区：[1]吉林省区域地质矿产调查所,吉林长春130022

出　　处：《吉林地质》2001年第2期1-9,共9页Jilin Geology

摘　　要：当把全球性洋陆结构体制用于区域性地质构造、特别是大陆古造山带研究时 ,我们发现还存在着一种“块带结构体制”区。本文所讨论的东北亚古吉黑造山带即是其中一例。古吉黑造山带 ,在空间上指松辽平原及其以东的吉林和黑龙江二省的东部山区。在时间上是指新元古代—早、中三叠世的造山演化历史。该区从新元古代起 ,就存在着晚太古宙所形成的松嫩、佳木斯、兴凯和龙岗等地块 ,及挟持其间的陆缘活动带 ,它是由古、中元古宙变质岩花岗岩系为结晶基底所形成的过渡型陆壳 ,从而构成了一个典型的块带结构体制区。通过阿森特兴凯期的弱造山 ,加里东期的次弱造山 ,早华力西期的次强造山和晚华力西期—早印支的强造山 ,使过渡型陆壳在造山作用的岩石圈深部动力学过程中 ,实现了壳幔能量和物质的交换 ;通过地幔物质的添加、陆壳物质的再循环 ,以英云闪长质深成岩垂直增生的模式 ,得到增长的同时成熟度不断提高 ,最终实现了向成熟陆壳的转化 ,并和诸地块实现了一体化 ,成为东北亚复合大陆的重要组成部分。这一过程 ,在陆壳物质成分的演化上表现尤为明显。无论是沉积物还是火山和侵入体的物质组成 ,总体上都向着富硅、富碱、特别是富钾的方向发展。作为造山带演化结束、成熟陆壳形成、复合大陆诞生的物质成分标志—?After studying regional geological structure with a global ocean-continental structure system, especially paleo continental orogenic belt, it was found that there is 'a block-belt structure system', an orogenic belt of Northeast Asia is one of them.\;The paleo Jihei orogenic belt means the Songliao plain and its eastern part of Jilin province and the eastern mountain area of Heilongjiang province in space. It belongs to Neoproterozoic in age. From the Neoproterozoic, the Songnen, Jiamusi, Xingkai, Longgang blocks and epicontinental mobile belt were formed in late Archean. It is a transitional continental crust formed by the paleo, middle Proterozoic metamorphic rock granite series as crystalline basement thus forming a typical block-belt structure system area.\;Through Assyntian-Xingkai weak orogeny, Caledouian sub-weak, Orogeny, early Variscan sub-strong orogeny and late Varisan-early Indosinian strong orogeny, the transitional continental crust brought about an exchange of the crust-mantle energy and substance during the lithosphere deep dynamic metamorphism of the orogenesis. Through an increase of the mantle substance, recirculation of continental crust substance, as a vertical accretion model of tonalitic plutonite with continuous growth and maturation, a mature continental crust was finally formed, becoming a whole body with other blocks and a major part of the compound continent in Northeast Asia.\;The evolution process of the composition of continental crust is very obvious. All the substances, whether they are sedimentary, volcano or intrusive, in general, formed gradually towards rich silicon and rich alkaline, especially to rich potassium. As the results of development of orogenic belt, forming a mature continental crust, and indication of substance composition of compound continent forming-molasse and 'A' type structure granite belt, the average composition(Wt×10 -2 ) is respectively SiO 2 67 80,75 58;K 2O+Na 2O 6 59,8 41;and K 2O/Na 2O 1 96,1 16, showing some characteristics with rich

关 键 词：古吉黑造山带 块带结构体制区 陆壳增生 复合陆块 

分 类 号：P542.2[天文地球—构造地质学]