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The character and interpretation model of deep structures in the Kelasu belt are discussed from growth strata, thrusting sequence, salt accumulation, and imbricate patterns between the shallow and deep structures. Seismic data shows that the fold hinges of growth strata in the south limb migrate toward north from deep to shallow, the growth axial surface connected along these fold hinges dips southward, and strata thickness in its south are thicker than that in the north. These characteristics of growth strata are completely different from that of basement-involved structures and salt structures. By the kinematic analysis of faults on the southern and northern sides of the Kela-2 structure, the northern fault is considered to thrust northward and form Kela-2 structure firstly, and then be cut through by the southern fault. Strong thrusting of the southern fault caused the Kela-2 structure to uplift several kilometers, and made the peripheral plastic rocks passively flow and accumulate in the footwall, this course is very similar to the pump suction. Based on this model, the sub-salt and sub-coal thrusting systems are interpreted in the deep Kelasu belt. In the sub-salt structural layer, the remaining lower part of Kela-2 structure in the footwall of its southern fault is the northern Keshen anticlinal belt. The discovery of the northern Keshen anticlinal belt and the Jurassic sub-coal thrusting structures greatly widens the exploration scope of the Kelasu belt, showing an enormous exploration potential. 摘要: ： 从构造生长方式、冲断序列、盐聚集以及深浅层构造的叠置关系探讨克拉苏深部构造的性质与解释模型。地震反射资料表明，克拉苏深部构造南翼生长地层的褶皱枢纽由深至浅向北偏移，这些枢纽连线构成的生长轴面南倾，其北侧地层的厚度明显要比南侧薄，此种生长地层结构与基底卷入式构造和盐构造作用下的生长地层结构完全不同。通过对克拉2构造南北两侧断层的运动学分析，认为北侧断层首先向北逆冲形成了克拉2构造，然后被后期更强烈的南侧断层切割，造成克拉2构造逾千米的垂向抬升，由此产生“泵吸”效应使周围塑性岩层向断裂下盘流入和聚集。据此模式建立的克拉苏深部构造解释方案由古近系盐下和侏罗系煤下两套冲断系统组成，其中在盐下构造内部，被切割的克拉2构造的下半部分即是克深北背斜。克深北背斜带和侏罗系煤下冲断构造的发现，不仅拓宽了克拉苏构造带的勘探范围，也显示其尚有巨大的勘探潜力。图8参25 Key words: growth strata, pump suction, salt accumulation, sub-salt thrust system, sub-coal thrust system, Kelasu structural belt

The Tarim Craton, China, records several significant events in the history of the Rodinia supercontinent, including Neoproterozoic glaciations and rift evolution. In this study, we use geochronological, geochemical, and geophysical data from the Aksu region, northwest Tarim Craton, to investigate the rifting history and three discrete Cryogenian glaciations in the Tarim Craton. A total of 268 concordant zircon U–Pb ages were obtained from three samples in the lowermost unit of the Cryogenian Xifangshan Formation. These ages define four Neoproterozoic populations of ca. 975–900, 885–810, 795–755, and 740–720 Ma, which reflect magmatic events in the Rodinia supercontinent. The age of the Xifangshan Formation is constrained by two maximum depositional ages of 739 ± 9 Ma and 719 ± 7 Ma, suggesting a stratigraphic correlation with the Cryogenian Baiyisi Formation in the Kuruktag region, northeast Tarim Craton. Field and geochemical evidence identify three discrete Cryogenian glaciations in the Aksu region, which are the Xifangshan, Qiaoenbrak, and Youermeinark glaciations that can be chronologically correlated with the Baiyisi, Altungal, and Tereeken glaciations in the Kuruktag region, respectively. The northern rift basin in the Aksu region formed at ca. 740 Ma and is filled by a thick Cryogenian volcanic–sedimentary succession. This rift basin gradually expanded to entire northern Tarim Craton, with sediments being unconformably deposited on underlying formations. Although large-scale deformation occurred in the late Ediacaran, corresponding to the Pan-African orogeny, the Aksu rift depocentre was covered with a series of deep-water rocks in the Early Cambrian and Ordovician. [ABSTRACT FROM AUTHOR]