限制型S状构造及其模拟——以铜陵地区为例

亚洲东部多数北东向构造带大都呈S状弯曲,研究其特征和力学成因,对于探讨大陆边缘的构造演化及运动方式具有重要意义。 下扬子褶皱带整体呈S状弯曲,它被一系列近东西向半隐伏断裂截接。构成许多东西向长条状地块,块内的次级褶皱也都呈S状弯曲。 本文选取铜陵地区为例,按照一定边界条件进行了递进变形模拟实验和有限单元分析。获得了预期结果,并根据递进变形的应变场测定λ1和λ3的轴长比所做回归分析曲线与实验曲线也是一致的。

S-SHAPED STRUCTURES OF RESTRICTIVE TYPE & ITS SIMULATING EXPERIMENT-TAKING THE TONGLING AREA AS AN EXAMPLE

Most NE trending tectonic zones in the eastern Asia area are curved in S-shape. So it is very significant to study the character and mechanism of the S-shaped structures for the consideration of the tectonic evolution and the pattern of tectonic movement in the continental margin of the eastern Asia. On the whole the lower Yangtzi fold belts like a capital letter S in shape. It has been cut by a series of faults with E-W trend. So a lot of rectangular massifs with E-W direction have been formed and the folds of secondary order are also curved in S-shape within the massifs. In this paper the Tongling area is taken as an example. According to certain boundary condition, the model experiments of progressive deformation and finite element analysis are made and some expected results are got by us. From the Strain field of progressive deformation, the ratio of axial length between axial length of ?1 and ?2 has been determined and the results of regression analysis in concordance with the experimental curves.