准噶尔盆地古隆起的分布与基本特征

DISTRIBUTION AND TECTONIC FEATURES OF PALEO-UPLIFTS IN THE JUNGGAR BASIN

准噶尔盆地外侧三大边界动力体系的作用及基底结构的差异性导致准噶尔盆地在不同地质时期发育不同性质的隆起构造。石炭纪晚期东北侧的造山作用形成了盆地北部隆起,晚二叠世北部隆起分异为陆梁隆起与乌伦古坳陷;早二叠世西北侧的造山作用形成了车排子隆起,随后的冲断作用形成了克拉玛依—夏子街断裂带。燕山期的压扭作用形成了沉积盖层中的车排子—莫索湾隆起。新生代北天山向北的冲断作用导致准噶尔盆地南部地区急剧挠曲沉降,盆地向南掀斜,隆起向北迁移。据基底的性质、形成时间、活动方式、地质结构与保存状态等特点将准噶尔盆地的隆起划分为继承型、间断型、掀斜型与冲断带型等4种基本类型。

The processes of tectonic dynamic systems along the three peripheries of the Junggar Basin and the diversity of the basement framework resulted in that the uplift structures with different behaviours developed in the Junggar Basin during varied geohistorical periods. The orogeny outside the northeastern boundary during Late Carboniferous produced the Northern Rise of the basin, which differentiated further to be the Luliang Uplift and the Wulungu Depression in Late Permian. While the orogeny outside the northwestern boundary during Early Permian brought about the creation of the Chepaizi Uplift, and the followed thrusting gave rise to the Kelamay? iazijie thrust belts. The transpression during the Yanshanian orogeny resulted in the Chepaizi-Mosuowan Uplift in the sedimentary cover with a SW-NE strike. The northward expansion of thrusting in the areas of Northern Tianshan Mountains during Cenozoic caused a rapidly flexural subsidence in southern part of the Junggar Basin, accompanied with the southward tilting of the basin interior, and the northward migration of the fore-bulges. Based on the characteristics of the basement, the formational ages, the kinematic styles, the geologic structures and the preservation of uplifts, the paleo-uplifts in the Junggar Basin could be classified into four basic types, namely, the successive type, the discontinuous one, the tilted one and the thrust belt uplift. The main tectonic features of each type of them were summed up, which showed that the uplifts played a great and characteristic role in the accumulation and distribution of oil and gas in the Junggar Basin.