库车坳陷西秋里塔格构造带新生代沉降史分析

The Analysis of Cenozoic Subsidence History of the Western Qiulitage Tectonic Belt in Kuqa Depression

根据地震资料和钻井资料,应用PRA公司的BasinMod 1-D软件,利用回剥技术对西秋里塔格构造带的4个井点和邻区的两个井点进行沉降史模拟。模拟结果表明,新生代以来基底总沉降曲线与构造沉降曲线相似,沉降曲线呈上凸式。克拉苏构造带和拜城凹陷的沉降史特征与西秋里塔格构造带的沉降特征总体相似,只是各阶段的沉降速率、沉降量不同,反映了构造运动从北向南传递,沉降中心从北向南迁移的过程。西秋里塔格构造带的沉降特征主要分为5个阶段,这5个阶段的曲线形态由缓到陡,反映了新生代以来西秋里塔格构造带一直处于挤压的应力环境中,且挤压程度由弱到强,直到第四纪最终定型,为典型的前陆盆地沉降特征。亦反映了天山造山过程中,库车冲断褶皱带由北向南推进,并最终到达秋里塔格构造带的过程。

We model the subsidence history of four well points in the western Qiulitage tectonic belt and two well points in the neighbouring areas with the help of the BasinMod 1-D software of Platte River Associates,Inc.and the backstripping technology on the basis of seismic datum and well boring datum.The result suggests that the total subsidence curve of the basement resembles the tectonic subsidence curve since Cenozoic and the subsidence curve presents convex shape.The subsidence history of Kelasu tectonic belt...