中国大地构造几个重大问题的探讨

DISCUSSION ON SOME KEY PROBLEMS ABOUT THE GEOTECTONICS OF CHINA

中国大地构造需要研究的重大问题甚多 ,文中选择了其中的 4个加以讨论。首先是大地构造发展演化的动力学理论。现在流行的按密度差、温度差建立的地幔对流、拆沉作用、地幔柱理论 ,阐明不了中国大陆岩石圈、大陆造山带的组成、结构与演化。我们的研究成果表明 ,任何一个自然形成的系统 ,其运动与演化的能源 (或力源 )都来源于它的自身 ;它内部的变形和结构几何学特征 ,也是它自身运动的结果。为此特提出在地球自转速度变化制约下的多层扭动涡旋甩出说———核幔壳“风暴”所引发的热核反应是地球发展与演化惟一的、统一的动力来源。第二 ,地槽、板块是涡旋甩出构造体系中的一种运动方式、一种造山模式。此外 ,我们根据秦岭和其它造山带所总结出来的抽拉逆冲岩片构造 (或抽拉构造 )也是大陆岩石圈板块或壳块内部的一种新的运动方式 ,它是继地槽学说、板块构造理论以后一种新的造山模式。文中较详细地介绍了抽拉构造理论的基本特征。第三 ,中国大陆岩石圈在中—新生代时期、在陆相沉积盆地形成以后、在抽拉构造体制作用下所形成的 (陆内 )造山带以及它们之间的残留陆相 (或海相 )沉积盆地 ,是中国大地构造的基本特征。陆内造山作用是中国大陆划时代的造山作用 ,所形成的造山带是中国大陆最重要的造山带。?

This paper intends to study four geotectonic problems of China. The first one is the dynamics of the development and evolution of geotectonics. Current theory of mantle convection and delamination and mantle plume proposed on the basis of the difference in density and temperature is poorly accepted and is unable to explain the composition, structure and evolution of continental lithosphere and continental orogen of China. The research results show that the energy (or driving force) for movement and evolution of any natural system comes from the system itself. The system’s internal deformation, structural and geometric feature are also the result of self\|development. As a result, the authors put forward the theory of multiple\|layer twisting vortex and throw\|out, or “typhoon”(or storm) of crust and mantle (or core) controlled by variations in the spin velocity of the earth. The thermal nuclear reaction resulted from this mechanism is the only universal energy source for the dynamics of the evolution and development of the earth. Secondly, geosyncline or geological plate is a way of moving and a kind of orogenic model in the thrown\|out vortex system. Furthermore, the drawing\|out thrust sheet tectonics generalized from researches in Qinling and other orogens is also a new way of moving within continental plate or crustal plate. It is also a new orogenic model developed after the geosyncline and plate tectonic theory. In this paper, the basic features of drawing\|out tectonics are introduced in detail. Thirdly, in Mesozoic, intracontinental orogenic belts formed by drawing\|out tectonism after the formation of continental sedimentary basins and the residual continental (or oceanic) sedimentary basins are the fundamental features of continental tectonics of China. Intracontinental orogenesis is the determinative orogen in continental China and orogens formed by it are the most important ones in China. According to the reality of China, intracontinental orogen may be classified into two types, that is, the one formed after intraplate oceanic basin and the one formed after continental basin. Fourthly, the close combination of metallogenesis with ore\|forming background should be an important task of geotectonic research work. The theory of twisting vortex and throw\|out, the ore\|controlling mechanism of multiple sheets and the controlling of drawing\|out tectonics on metallogenesis can be used to explain the source of minerals and the enriched location of mineral resources. They are also helpful in mineral predicting and prospecting. Correctly understanding the geological rules and properties of nature is essential to the study of environment protection, of geological hazard prediction, of global changes and of sustainable development.