中国大地构造简述

我国的地质工作,自解放以来,在毛主席的革命路线指引下,获得迅速的发展,积累了丰富的资料。特别是自无产阶级文化大革命以来,以及在批林批孔运动的推动下,取得了更加重大的成就,全国地质情况已普遍作过查勘。这使构造地质工作者有条件在前人大量劳动成果的基础上,对中国大地构造从事进一步的总结和综合研究。

A BRIEF REVIEW ON THE GEOTECTONICS OF CHINA

On the basis of new data a new research work on the geotectonics of China has been made from the viewpoint of Chen Guoda’s theory of "diwa"1) or geodepressionand its extension——the theory of progression (with transformation between mobile and"stable" regions). The analysis of geological history has been integrated with the consideration of structural stresses. Some of the geotectonic characteristics of the country may be summarized in the following.The theory of progression as well as the theory of diwa (geodepression) has been developed on the basis of the conventional theory of geosyncline-platform (Hall, J. 1859, Dana, J. D. 1873) by specifying a post-platform mobile stage of diwa in the evolution of the earth crust.2) The theory has been substantiated by the geological data of China, E. Asia, B. Africa, Europe and N. America. Its main points imply that the development of the crust tends to follow a spiral course upwards, mobility alternates with stability in the form of transformation, the simple structure develops to the complex as does the lower to the higher in successive stages3)In China, 20 geotectonic regions may be divided. There are 5 geosyncline regions, i.e. the Kunluen (Hercynian), the Bayanhar (Pacificean), the Gangdise (Pacifician), the Himalaya (Himalayan), and the Taiwan (Himalayan); 3 platform regions, i.e. the Ordos (post-Luliang or post-proterozoic), the Szechuan (post-Jinning or post-middle Sinian), the Sung-Liao (post-Hercynian) : and 11 diwa regions, of which the SE. China, the Yunnan-Guizhow, the Central China, the N. China, the NB. China, the NS and the W. Yunnan being of the Cathaysian stage (Mesozoic); the N. Sinjiang, the S. Sinjiang, the Qinghai-Gansu, and the N. Xizang being of the Central Asian stage (Cenozoic). The last region is that of the S. China sea, of which the geotectonic character needs further research.The crust of China is composed of 2 major blocks, or the W. and the E. halves, with the N-S diwa region in between. The 2 halves manifest a sharp contrast in geotectonic history and characteristics, structural trends and systems, landforms, geophysical properties, crust thickness, and in the depth of the Moho surface. They also differ greatly in the mode of tectonic movement, the direction of the horizontal and vertical movements, metallogenesis, and in seismicity. Between the 2, the N-S diwa region is a narrow belt of fracture zones 2000 km long, in which lies the abyssal fault of Yinchuan-Kunming. It characterizes the transition between the 2 halves in all geotectonic aspects.