摘要
板块学说发展史上存在着造山作用的仰冲和俯冲两种成因观点。俯冲说难以解释中脊俯冲、板缘构造、板内变形及海沟构造。仰冲说认为板块会聚边缘处在两个相向运动着的对流系交会带。根据板缘构造平、剖面特点,结合威尔逊旋回、板块运动史、地壳结构等分析,大陆仰冲板块是在克服属弱对流系一方的洋板块的抵抗,迫使贝尼奥夫带不断向洋退却过程中向前推进.而造成各种板缘和板内构造的变形机制的。据此,提出一个断续仰冲模式以代替传统的连续俯冲模式。用仰冲观点分析了形成板内变形的内、外条件和常见的变形型式。还试用板内仰冲作用来解释华南加里东期构造特点与钦州地槽之谜。
There are two original viewpoints, obduction and subduction, in the development history of plate tectonics theory. It is difficult to explain the subduction of mid-oceanic ridge, marginal plate structuras, inner-plate deformation and oceanic trench structures by the plate subduction theory. But the plate obduction theory considers that convergent boundary is located along intersecting zone of two convection systems moving to each other. Study on marginal strutural planes and sections in combination with Wilson cycles, plate movement history, crustal structure, etc. , shows that continental obduction plate advances towards ocean by overcoming oceanic plate of the weaker convection system and forcing Benioff zone to withdraw continuously, which results in the deformation of marginal and inner plate structures. Hence, the author proposes an intermittent obduction model instead of the traditional continual subduction model The author also analyzes the conditions of inner - plate deformation and common deformation types by using plate obduction viewpoint, and tries to use inner - plate obduction to explain the Caledonian structures in South China and discover the mystery of Qinzhou geosyncline.
