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关于沉积差异负载对褶皱-冲断带中塑性盐岩变形的影响仍然不清楚,库车褶皱-冲断带拜城凹陷受到的构造挤压变形微弱,凹陷中沉积了巨厚的盐上覆层,是研究沉积差异负载如何影响塑性盐岩变形的天然实验室.根据野外地表调查结果、钻井资料和二维地震剖面,约束库车褶皱-冲断带拜城凹陷盐构造特征,并探讨盐构造成因机制.盐顶构造图揭示拜城凹陷盐上覆层发育东、西2个沉积中心,东沉积中心位于拜城县附近,西沉积中心位于BZ1井南侧,二者之间(大宛齐乡附近)形成大宛齐盐枕和拜城凹陷鞍部.钻井资料和地震剖面显示:(1)东、西沉积中心下伏盐岩流动减薄,二者之间盐岩聚集加厚;(2)大宛齐盐枕核部盐岩聚集发生于上新世晚期-现今;(3)上新世末期-现今,拜城凹陷鞍部下伏盐岩聚集加厚,盐岩厚度往东、西沉积中心逐渐减薄,形成东西向背形构造.基于盐构造特征和前人研究成果,提出库车褶皱-冲断带拜城凹陷盐构造相关的盐岩流动变形模型,认为沉积差异负载在库车褶皱-冲断带盐岩变形中发挥着重要作用:(1)在挤压应力和沉积差异负载作用下,以东、西沉积中心为圆心,盐岩向四周放射状流动;(2)盐岩变形以沿挤压方向(N-S)流动为主,但剖面间(E-W)流动也很明显.
The effect of differential load on the deformation of plastic salt rock in the fold-thrust belt is still unclear. The Kuqa fold-thrust belt has a weak compressional deformation of the structural depression in the Baicheng sag, with thick salt overburden , Is a natural laboratory to study how the differential loading of sediment affects the deformation of plastic salt rock.According to the field surface survey results, drilling data and 2D seismic profile, the salt structural features of the Baicheng depression of the Kuqa fold-thrust belt are constrained and the salt structure The mechanism of the salt top tectonic map reveals that there are two sedimentary centers in the east and west of the salt overburden in the Baicheng depression, the east sedimentary center is near Baicheng County, and the west sedimentary center is located south of the BZ1 well. Dawushu salt pillows and the saddle of the Baicheng sag.Drilling data and seismic sections show that: (1) the salt rock flows are thinner beneath the sedimentary centers in the east and west, and the salt rock thickens between them; (2) (3) Late Pliocene - Nowadays, the underlying salt rock in the saddle of the Baicheng sag thickens, the thickness of the salt rock goes east and west, The center is gradually thinned to form an east-west dorsal structure based on the structural features of the salt According to the previous research results, the paper presents the salt deformation model of salt rock associated with the salt formation in the Baicheng sag of the Kuqa fold-thrust belt and argues that the sedimentary differential load plays an important role in the deformation of salt rock in the Kuqa fold-thrust belt: (1) Under the load of compressive stress and sedimentation, the salt rock flows radially around with the center of the east and west sedimentary centers. (2) The deformation of rock salt is mainly along the NS direction. However, between the cross sections (EW Flow is also obvious.