摘要
专家们对华北陆台早前寒武纪基底构造格局形成与演化的认识既有共同点又有分歧。共同点是太古宙为形成刚性小陆块的时期 ,其成因可能与地幔柱的垂直增生有关 ,如TTG质岩类的大量增生与侵位。小陆块的构造拼合形成华北克拉通的主体。分歧焦点是陆块拼合的时代 :第一种认为小陆块的拼合发生在新太古代 ,即华北陆台在新太古代就已克拉通化 ,到古元古代时在伸展构造体制作用下 ,形成了一系列的裂谷或拗拉谷。第二种认为拼合发生在古元古代 ,即华北陆台是吕梁运动才克拉通化的。
There are two different ideas about the tectonic division of North China Block (NCB) basement and its evolution in early Precambrian. (1) Many microblocks formed through the vertical accretion of plume during Archean period especially during New Archean period. Then they got larger and larger through the subduction accrection, and finished its cratonization at about the end of Archean (～2.5 Ga). By the end of Poleoproterozoic (～1.8 Ga) NCB craton was in an extensional tectonic regime, associated with the development of an aulacogen system. (2) NCBs crotonization took place not in Archean but in Paleoproterozoic. Many microblocks collided and formed larger blocks. In the late period of Paleoproterozoic, there were two large blocks lying in the eastern and western parts respectively, their collision results in the crationzation of NCB, and aulacogen system formed later on.
出处
《前寒武纪研究进展》
2000年第1期54-63,共10页
Progress in Precambrian Research
关键词
华北陆台
基底构造格局
形成
演化
陆台
North China Block
tectonic division
formation and evolution
