摘要
在过去的二十年里 ,华北克拉通早期陆块形成和演化的研究进展是中国固体地球科学研究领域最为显著的成果之一。第一个十年代表性的工作包括深变质变形的层状岩系与块状岩系的识别与成因研究、高级区与绿岩带的划分、构造样式与变形序列研究、变质历史与变质动力学、年代学与地质事件的研究等。第二个十年的研究重点是如何认识和理解早期大陆地壳的性质和它们的形成与演化过程。代表性的进展包括均匀域与地质体的划分、古老微陆块的识别、残留洋壳与早期陆壳的形成、下地壳组成和性质、大陆拼贴机制、古地幔柱构造与前Rodinia超大陆旋回等。其中高压麻粒岩地体和退变质榴辉岩的发现 ,是华北早前寒武纪研究中最重要的进展 ,它为早期大陆的拼合机制、地壳的深部结构和古老下地壳与现代的对比等多个领域打开了新的研究思路。对新太古 -早元古代的重大地质事件的厘定已表明 ,华北主要的地壳生长期是在 2 9～ 2 7亿年 ,但 2 5和 18亿两期事件是重大的事件 ,虽然对其性质尚存争议 ,但越来越多的证据把它们与超大陆和地幔柱构造相联系。
The one of most important advances of earth sciences in China is early formation and evolution of North China continental block in last two decades.The representative advances in the first decade in clude understanding of layered rock sequences and massive rock sequences,division of greenstone belts and high grade metamorphic regions,tectonic styles and structural analyses,metamorphic history and dynamics,geochronology and significant geological events.The representative advances in the second decade include distinguishing old continental micro blocks and terrenes,remnant ancient ocean crust and junior continent crust,composition and texture of Precambrian lower crust,amalgmation and break up of supercontinent,early Precambrian plate tectonics and plume tectonics.The most important contribution should be the discovery of high pressure granulites and eclogites,which greatly improves study on some geological prospects,especially in tectonic mechanism of old continent formation and evolution. A lot of study indicate that the main growth period of the North China craton is during 2.9～2.7 Ga, however the most intensive and significant tectonic events took place during 2.6～2.45 Ga and 1.9～1.75 Ga, for which more geological evidence seem support a supercontinental tectonic model to understand.
出处
《前寒武纪研究进展》
2001年第1期17-27,共11页
Progress in Precambrian Research
基金
国家基金!委项目 ( 4 9832 0 0 3
4 9872 0 64
4 0 0 72 0 61)
中科院重大创新项目! (KZCX1- 0 7)
