塔里木盆地北缘沙雅隆起两阶段走滑变形的证据

沙雅隆起（塔北隆起）是塔里木盆地北缘极为重要的近东西向构造带。前人研究认为，沙雅隆起以逆冲变形为主，但是，这一认识既与地震剖面上的花状构造样式相矛盾，又与平面图上断层呈扫帚状和拖尾状分布的特征相矛盾。该文基于高分辨率的三维地震剖面，提出塔里木盆地北缘沙雅隆起经历了2个阶段的走滑构造变形：第一阶段为加里东晚期—印支期的压扭构造变形，形成了深部构造层中的大型正花状构造，同时地层被大幅抬升并遭受剥蚀；第二阶段为喜马拉雅期的负反转—张扭构造变形，形成了浅部构造层中的负花状构造。这一认识表明，塔里木盆地北缘可能并非统一的构造—沉积环境，沙雅走滑构造带为一重要的构造—沉积分隔带，而加里东晚期与喜马拉雅早期是塔里木盆地北缘非常重要的2个构造变革期。

Evidence of two-stage strike-slip structural deformation of Shaya Uplift,northern Tarim Basin

The Shaya Uplift, an important structural belt in the northern Tarim Basin, northwestern China, has been regarded as a thrust belt. However, this recognition is not only incompatible with the flower structures on the seismic profiles, but also contradictory with the fault distribution in a broom or trailer mode in plan view. High-resolution 3D seismic profiles indicate that a two-stage strike-slip structural deformation happened in the Shaya Uplift. The first is from the Late Caledonian to the Indosinian, in which transpressional deformation occurred and a huge positive flower structure was thus formed in the deeper part, and strata were eroded because of the structural uplifting. The second is during the Himalayan, in which a negative inverted/transtensional deformation occurred and a negative flower structure was formed in the shallower part. These results indicate that it is not a uniform tectonic-sedimentary environment in the northern Tarim because of the Shaya Uplift barrier and that the Late Caledonian and the Early Himalayan may be two important structural transformation periods.