含滑脱层剖面的分层平衡恢复技术在川东北构造演化研究中的运用

在利用平衡剖面技术对古构造演化的研究中,常常遇到塑性层的不规则变形而使得剖面难以达到平衡的问题,利用分层组合法可以消除塑性层所造成的影响。将盐上岩层和盐下岩层分开平衡恢复,然后利用二者控制盐层并组合到一起,以此控制塑性层的变形幅度,使剖面达到平衡状态。分层组合法运用到针对川东北地区晚古生代—中生代地层的构造演化研究的平衡剖面技术中,较好地消除了塑性层所带来的影响。研究结果表明,川东北地区古构造的形成经历了早期拉张、中期过渡、后期挤压的受力变形过程,由此而形成了早期发育正断层、中期构造发生反转、后期大量逆冲推覆构造发育的构造特征,嘉陵江—雷口坡组厚达500 m的膏盐岩层在变形过程中起到了重要的滑脱、调节作用。

Applying Balanced-restoring Technique with Detachment Horizon Profile to Study the Tectonic Evolution of Northeastern Sichuan

In the research of tectonic evolution with the balanced section technique,there is some difficulty in achieving the balance of the section because of the irregularly plastic deformation of the layer.To solve this problem,the layered technique is proposed to eliminate the influence of plastic layer,that is to recovery the formations which are on and under salt rocks respectively,then the salt is controlled by both of them to dominate the deformation amplitude,and finally the balanced state is achieved.The pr...