宁镇山脉汤—仑推覆体前锋带构造型式及形成机制初探

推覆体前锋带是推覆体的重要组成，其变形特点既反映了推覆体发展过程中的推覆动力的作用和应力消失，又反映了受外缘抗阻的相互作用，这方面的研究受到国内外构造学家的关注。推覆体前锋带的变形构造在组成上既有推覆系的组成，又有逆推覆方向上前锋－外缘带的被动变形构造组成，形成了推覆体受阻状态下的复合变形构造。发育在宁镇山脉的汤—仑推覆体前锋带上的变形构造存在五种型式：岩层的大幅度旋转与密集的叠瓦系；反冲构造；具捩断层性质的横向及斜向断层；平卧褶曲的翘起和具优选剪切方位的膝折构造。

STRUCTURAL TYPES AND FORMATION MECHANISM FOR THE FRONT ZONE OF THE TANG-LUN NAPPE,NINGZHEN MOUNTAIN

The front zone of a nappe is an important component part of a nappe. Its deformation expressesboth the push action and stress release during the nappe development and the interaction with theouter margin. Tectonists pay attention to this problem. Deformational structures at the front of anappe have both the component of the push system and the component of the passive deformationalstructure at the front - outer margin zone in the reverse direction to push, forming compound defor-mational structures in the state that the nappe suffers from resistance. There are five types of de-formational structure in the front zone of the Tang-Lun nappe, Ningzhen Mountain: great rotating ofbeds and imbricated system; reversed structure; transverse and oblique faults with the character oftear faults; warping of recumbent folds and kink band with advantageous shearing direction.