中国(东亚)大陆受特提斯、古亚洲和太平洋构造体系的制约,具有复杂的地体构架和特殊的岩石圈结构。本文从地学前沿——大陆动力学的视野出发,围绕中国大陆构造及动力学四个方面的研究,总结已有的进展并提出新的思考:①中国大陆板块下的构造和整个地幔运动的构架:地震层析资料揭示西太平洋板片向西俯冲到东亚大陆之下,其倾角逐渐减小,最后近水平地插进400~600km深度的地幔过渡带中,成为箕状几何形态的超深俯冲板片。印度岩石圈板片超深俯冲至青藏高原之下~800km的深度,在喜马拉雅西构造结部位发生双向不对称深俯冲,印度岩石圈板片向东俯冲至东构造结东侧之下300~500km的深度。②中国大陆变质基底的再活化:中国大陆的大部分陆块未受显生宙以来构造、变质和岩浆事件的改造与激活,在冈瓦纳大陆北缘的印度陆块和阿拉伯陆块北缘还发育有形成于泛非期(530~470Ma)的造山带,其影响范围至高喜马拉雅、拉萨地体和三江地区。新生代的变质活化普遍出现在喜马拉雅、南迦巴瓦、拉萨地体和三江-缅甸地区,最新的变质年龄仅2~1Ma(南迦巴瓦)。③中国主要高压-超高压变质带的大地构造背景及深俯冲-折返机制:中国及邻区含榴辉岩的高压-超高压(HP/UHP)变质带有洋壳(深)俯冲和陆壳(深)俯冲之分。青藏高原中,大部分洋壳俯冲形成的高压/超高压变质带与原-古特提斯洋盆中诸多微陆块之间的小洋盆的汇聚碰撞有关,陆壳深俯冲作用有两种机制,它们分别是大陆块之间剪式碰撞和撕裂式岩石圈舌形板片的深俯冲。④中国大陆造山带的深部物质可经3类机制挤出,即深部地壳物质"牙膏式"挤出、侧向挤出和"挤压转换式"挤出。
The Chinese continent,which is strongly constrained by the Tethyan,Paleo-Asian and Pacific tectonic systems,is characterized by a complex tectonic framework and a particular lithospheric structure.Based on the theory of continental tectonics and dynamics,here we provide a comprehensive overview of recent research results with a particular attention to four important scientific problems on the Chinese (East Asian) continent.①Tectonics of the mantle beneath the Chinese continental lithospheric plate.Seismic tomographic profiling reveals that the western Pacific slab is subducted westward to depths of 400~600km beneath the East Asian continent,and the subducted slab becomes subhorizontal and listric-shaped in the mantle transitional zone.The Indian slab is subducted northward to a depth of ~800km far north under the Banggonghu-Nujiang sutute zong between the the Lhasa and Qiangtang terrains.Double subductions are asymmetrical beneath the western syntaxis of the Himalayan belt.In the eastern syntaxis,however,the Indian slab is subducted eastward to depths of 300~500km beneath the Burma-Sanjiang terrain.②Reactivation of the Chinese continent's metamorphic basements.Most blocks of the Chinese continent have not been reactived by significant tectonic,metamorphic or igneous events since the Phanerozoic.The north Indian and Arabian blocks (northern edge of Gondwana) were shaped by pan-African orogenic belts at 530-470 Ma.This tectonic field occurred mainly in the higher Himalaya,Lhasa terrain and Sanjiang terrain.The Cenozoic metamorphic reactivation appeared ubiquitously and uniquely in the Himalaya,Namche Barwa,Lhasa terrain and Burma-Sanjiang terrain with the youngest metamorphic ages of 2~1 Ma.③The tectonic backgrounds and processes for the formation and exhumation of HP-UHP metamorphic belts in China.The eclogite-bearing HP-UHP metamorphic belts in China formed in either oceanic or continental deep subduction zones.Most of the oceanic HP-UHP belts in the Tibetan plateau are related to the coll