“造山带研究”笔谈会

CONVERSATION BY WRITING ON “OROGENIC BELTS”

《地学前缘》编辑部遵循"百花齐放，百家争鸣"的方针，以笔谈会形式邀请10多位地质学家从不同角度阐述造山带研究的意义、理论和方法等。文中主要论述了下列内容：（1）关于造山带的涵义。对造山带的涵义有两种不同的认识：一种意见把造山带与板块间的相互作用密切联系，强调只有会聚板块边缘构造作用形成的地质体，才能称为造山带；另一种意见认为板内造山带是客观存在的，对大陆造山带的研究是大陆动力学的关键。（2）关于中国造山带的特点。中国地处3大体系──印度板块、太平洋板块和西伯利亚板块的交汇处，是古亚洲、特提斯和太平洋3大洋盆体系和其间诸多地块开裂、演化、增生、碰撞和消亡的结果。它们通常经历了长期的地质演化，形成了许多多期复合型造山带，而不完全与地球上一些典型的造山带相同。另一个特点是老造山带和已稳定地块在后期可再次卷入构造运动而活化。因此，中国是研究大陆开裂、增生、碰撞和拼贴作用的理想场所。（3）我们应当在总结中国各类造山带的地质。地球物理和地球化学等特征的基础上，结合东亚以至全球构造研究，创建大陆造山带的新理论。

Follow the policying of 'let a hundred flowers blosson and a hundred schools of thought contend', more than ten geologists are invited by the editorial department of 'Earth Science Frontiers' to take part in a writing conversation about the study of orogenic belts.They express opinions about the characteristics of orogenic belts in China, and discuss how to do the research works in order to establish new theory about orogenic belts. There are contra-dictory opinions about the meaning of orogenic belt. One considers the close relationship be-tween orogenic belts and plate tectonics, and emphasizes that the orogenic belts are the tectonic belts formed in the convergent margins of plates. The other considers that there are strong de-formed tectonic belts within the plate, which may be called intraplate orogenic belts, and the study of them is the key to know the continental dynamics. Being located in the junction part of the three systems, i. e. the Indian plate, the Pacific plate and the Siberian plate, the tectonics of China is the results of rifting, evolution, accretion, subduction and collision among the three giant basin systems,i. e. the Paleo-Asia, the Tethys and the Pacific Ocean, and those blocks scattered within them. Therefore, the orogenic belts in China usually experience a long geologic evolution history and form the multiphase composite belts which are more complex than some typical orogenic belts in the world. Another distinguishing feature of the tectonics of China is that the older orogenic belts and cratons could be involved in the late tectonic-thermal events,and formed intraplate or intracontinental orognic belts. Owing to these characteristics, so Chi-na is an ideal area for the study of continental rifting, accretion and collision. It is our duty to establish a new theory about the continental orogenic belts by means of summarising the charac-teristics of geology, geophysics and geochemistry of China to connect with the East Asia and global tectonics.