摘要:编制构造演化剖面可以对构造变形进行定量、半定量分析，对构造活动和演化研究具有重要意义。受伸展叠加走滑多期变形影响，复杂伸展盆地区断层、褶皱发育，为平衡剖面的恢复过程带来了一些困难和问题，影响了盆地演化分析的准确性。本文根据存在的问题，提出了一种利用Cdr（CorelDRAW）软件对复杂伸展盆地区变形进行恢复的新方法。该方法充分考虑变形、剥蚀和压实作用对恢复产生的影响，主要包括以下两个方面：1）地层恢复。如果浅部构造变形对深部影响不大，在恢复时采用层厚不变原则逐层进行回剥；若后期存在区域挤压作用，盆地整体发生构造反转形成褶皱，浅部每剥去一层，深部地层即相应消除该时期产生的应力叠加效应，此时需要对弯曲地层进行拉平处理。2）断层恢复。对生长断层而言，断层恢复就是消除上覆岩层产生的重力效应。对于深部早期生长断层而言，浅部地层对其只有压实作用而不影响其产状，此时应遵循深、浅部断层分开、独立恢复的原则。这种平衡剖面恢复的方法是基于地层及断层发育的构造部位、活动期次及其成因关系提出的，更加符合地质逻辑，能够更好地反演复杂伸展盆地区构造变形过程。运用该方法对渤海湾盆地济阳坳陷青西地区进行了平衡剖面反演，得出该区构造演化受控于伸展、构造反转和走滑影响。
关键词: 平衡剖面/
构造演化/
地层恢复/
断层恢复/
复杂伸展盆地区
Abstract:Restore tectonic evolution section can quantitatively and semi-quantitatively analyzes the tectonic deformation, which is of great significance for structural activities and evolution researches. Controlled by multi-period deformation of the superimposed extension and strike-slipping, the fault and fold developed in complex extensional basin brought some difficulties and problems to the restoration of the balanced section, which affected the accuracy of the basin evolution analysis. Based on the existing problems, a new method is proposed to restore structural deformation in complex extensional basins using Cdr（CorelDRAW）software. This method fully considers the effects of deformation, erosion and compaction on restoration, mainly including the following two aspects： 1）Stratum restoration. If the shallow structural deformation has little effect on the deep part, follow the principle that keep the layer thickness unchanged and restore the strata layer by layer. If there is regional tectonic compression in the later stage, the basin will occur overall structural inversion and form folds. When each shallow stratum is stripped off, the superimposed effect on deep strata generated during this period will be eliminated accordingly. In this case, the principle that level the curved strata should be followed. 2）Fault restoration. For growth faults, fault restoration is to eliminate the gravity effect of the overloading. And for deep early growth faults, shallow strata only have compaction on them without changing their attitude. So it is necessary to follow the rule that the “deep and shallow part should be restored separately and independently”. This method of restoring the balanced profile is based on the structural positions, active stages and genetic relationship between the strata and faults, which coincides with geological logic and can better inverse the structural deformation process in complicated extensinal basin. Using this method, two balanced profiles of the Qingxi area in Jiyang depression of the Bohai Bay Basin are restored. They indicated that the tectonic evolution of this area is controlled by extension, tectonic inversion and strike-slipping.
Key words:Balanced profile/
Tectonic evolution/
Stratum restoration/
Fault restoration/
Complex extensional basin
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