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阿恰构造带位于塔里木盆地西部,主要由阿恰断裂和乔来买提断裂组成,构成了塔里木盆地次级构造单元阿瓦提凹陷和巴楚断隆分界线的西北段。通过地震资料解释,将阿恰断裂带分为西段、中段和东段3部分。西段为基底卷入型单断逆冲构造样式,断层倾向巴楚断隆;中段为“Y”字形基底卷入型逆冲构造样式,除倾向巴楚断隆的主冲断层外,还发育倾向相反的反冲断层,开始显现出楔状冲断构造的轮廓;东段为典型的楔状冲断构造,倾向巴楚断隆的主冲断层向上断至中寒武统,其冲断位移量完全被倾向阿瓦提凹陷的反冲断层吸收。同时,在阿恰断裂的西段和中段,断层上盘还发育第四纪正断层,而断裂东段不发育。研究认为阿恰断裂带主要存在两期断裂构造:深部基底卷入型逆冲断裂带和其上叠加的浅部正断层。前者形成于新近纪库车组沉积前,在库车组沉积期间持续活动,并在新近纪晚期定型;后者是本次研究首次发现的,形成于第四纪早中期,且只发育在阿恰断裂带的西段和中段。
The Aqa structural belt is located in the western part of the Tarim Basin and consists mainly of the Aqa fault and the Qiaolamatu fault, forming the northwestern segment of the Awati Depression and the Bachu fault boundary in the Tarim Basin. According to the seismic data interpretation, the Aqa fault zone is divided into three sections: the western section, the middle section and the eastern section. The western segment is basal-inrush thrust fault type, and the fault has a tendency of Bachu faulting. The middle segment is a “Y” -shaped basal-infill thrusting tectonic style. In addition to the main thrust fault that favors the Bachu fault, But also the reverse tectonic fault with opposite tectonic setting, and began to show the outline of the wedge-shaped thrust structure. The eastern segment is a typical wedge thrust structure, and the main thrust fault that broke the Bachu uplift is upwards to the middle Cambrian. Its thrust displacement The amount is completely absorbed by the thrust fault that tends to the Awati Depression. At the same time, in the western and middle parts of the Aqa fault, the Quaternary normal faulting also developed in the fault upper plate, while the eastern segment of the fault did not develop. The study shows that there are mainly two phases of faulting in the Aqa fault zone: deep basement thrust belt and superficial normal fault superimposed on it. The former formed before the deposition of the Neogene Kuqa Formation and continued its activity during the deposition of the Kuqa Formation and was finalized in the late Neogene. The latter was first discovered in this study and formed in the early and middle Quaternary, Just the western and middle fault zone.