地表剥蚀、下地壳流变与造山作用研究进展  

Research Advances in Erosion,Rheology of the Lower Crust and Orogeny

作　　者：张新钰[1] 季建清[1] 韩宝福[1] 陈建军[1] 余绍立[1] 

机构地区：[1]北京大学地球科学与空间学院造山带与地壳演化实验室,北京100871

出　　处：《地球科学进展》2006年第5期521-531,共11页Advances in Earth Science

基　　金：国家自然科学基金项目"喜马拉雅中段与南迦巴瓦构造结变质变形剖面的对比研究"(编号:40472100);国家自然科学基金重点项目"强烈汇聚区大陆岩石层结构重组及其圈层相互作用"(编号:40234049)资助

摘　　要：岩石圈的流变特性研究已经成为固体地球科学研究中的重要领域,是地球科学新理论、新观点的重要渊源。最近的研究表明,下地壳普遍存在的韧性流是造山作用的重要制约因素。在下地壳物质层流变作用机制的调节下,地表剥蚀作用并不仅仅是传统意义上地表夷平的因素,它还能打破地壳动力学和热力学平衡,引起地壳内物质和结构的重置,进而促成山脉的加剧隆升;地表剥蚀作用的强度既受控于造山带的抬升,也受制于地球外圈层(大气圈、水圈、生物圈)。以天山山脉和喜马拉雅山山脉的隆起、喜马拉雅山山脉的变质作用以及相关的构造活动为例,说明在造山过程中,尽管传统意义上的造山作用与地球内部动力过程,即构造作用有密切联系,但是与构造运动的时空尺度不同,地表剥蚀作用也能够在相对较小的时空尺度内,通过影响和控制造山带下地壳的韧性流动,成为地壳抬升和造山带构造演化的重要动力因素。对地壳的流变特性和变质变形研究是当前地球系统科学研究的一个重要切入点。As one of the up-to-date frontiers of earth science, The research on lithosphere rheology has become an essential field in solid-earth research. Recent progresses show that the widely distributed ductile flow in the lower crust is one of the most important constraints in orogeny. Being controlled by the rheology of the lower crust, erosion may level off the topography, and ean break the balance of kinetics and thermodynamics inside of the crust therefore rebuild the structure and component of the eurst, the uplift process of the mountains is then enhanced ; we believe that the rate of the exhumation is controlled by both the uplift of orogen and the outer spheres of the earth （atmosphere, hydrosphere）. In this paper, as typical examples, the rapid uplift of the Tien-Shan and the Himalayas, the metamorphism and tectonics of the Himalayas. was discussed, our conclusion is that although traditional orogeny has a close relationship with tectonics, erosion can effectively control the ductile flow in the lower crust during the development of a mountain in a small time and space scale, and the coupling mechanism between erosion and ductile flow in the lower crust is crucial for crust uplift and tectonic evolution of great mountain ranges. The research on lithosphere rheology and deformation and metamorphism is an important cut-in point of earth system science.

关 键 词：地表剥蚀作用 下地壳 韧性流 造山作用 喜马拉雅山脉 天山 

分 类 号：P54[天文地球—构造地质学]