平衡剖面在焉耆盆地构造演化分析中的应用

STUDYING STRUCTURAL EVOLUTION OF THE YANQI BASIN WITH BALANCED-SECTION TECHNIQUE

平衡剖面技术是一种按照几何守衡原则而建立的地质剖面正演方法,是一种构造变形恢复的重要手段。研究中采用了Geosec软件对焉耆盆地9条构造剖面进行了复原和地层伸缩量计算。结果表明,燕山早期焉耆盆地处于弱挤压状态,构造变形量相对较小,而主要的变形量集中于燕山晚期和喜山期,并且喜山期变形稍弱于燕山晚期。平面上盆地西部变形量较大,东部变形量较小。盆地中、新生代的演化划分为3个主要阶段:燕山早期弱挤压与同生变形阶段,燕山晚期强烈挤压阶段,喜山期对冲挤压阶段。

Balanced-section technique is a forward-inversion method of geologic section.which is based on geometric conservation principle.It is an important means for the recovery of structural deformation.During study,using Geosec technique to make balanced sections of the 9 seismic lines and calculate the amount of extension and contraction of the for layer.The results show that Yanqi basin is in weakly compressive status in early Yanshanian with smaller amount of structural deformation.While main deformation is concentrated in late Yanshanian and Xishanian,but the deformation is weaker in Xishanian than that in Yanshanian.on the plane,deformation is stronger in west than that in the east of the basin,mesozoic-cenozoic evolution of the basin is divided into 3 stage,such as weak compression and syn-deformation stage in early Yanshanian,strong compression stage in late Yanshanian and face compression stage in Xishanian.