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应用区域地震台网1981-2011年的地震到时资料,对新乡及邻区地壳三维速度结构和震源参数进行了联合反演,获得了该区地壳的三维速度结构图像.结果显示:0~4 km深度层位的速度分布基本反映出了研究区浅部地形的分布特征,凹陷盆地速度低,山脉位于速度的过渡区,隆起区多位于高速区,横向速度分布差异较大;其余各深度层速度横向分布存在非均匀性,与地形分布特征也存在着一定的联系;速度剖面整体显示区域地壳可以分为上、中、下三个分层,上地壳速度横向变化较小;中、下地壳的界面速度横向起伏变化较大,局部地区呈现上隆或凹陷状;根据速度的分布差异,以及所勾画的深部断裂的轮廓展布,对该区的深部构造有了较深认识:汤西断裂、汤东断裂显示错断较深,倾角较陡,有延伸到中地壳底部的趋势;郑州-开封断裂带、新乡-商丘断裂,与人工地震剖面相同位置处及地质剖面有着较好的对应.
The 3D velocity structure and source parameters of the crust in Xinxiang and its adjacent areas were jointly retrieved using the time-of-arrival data of the regional seismological network from 1981 to 2011. Three-dimensional velocity structure images of the crust in the area were obtained. The results show that 0-4 The velocity distribution of the deep horizon basically reflects the distribution characteristics of the shallow terrain in the study area. The velocity of the depression basin is low and the mountains are located in the transition zone of velocity. Most of the uplift areas are located in the high-velocity zone with large differences in lateral velocity distribution. The horizontal distribution of velocity is inhomogeneous, which is also related to the topographic distribution. The whole crust of the velocity profile can be divided into upper, middle and lower strata, and the velocity of the upper crust varies little laterally. The middle and lower crust The velocity of the interface changes greatly in lateral fluctuation, and some areas show uplift or depression. According to the distribution of velocity and the contour distribution of deep faults, the deep structure of the area is well known: the Tangxi fault , The fault of Tangtang fault shows a deeper fault with a steeper dip and tends to extend to the bottom of the middle crust; the Zhengzhou-Kaifeng fault zone, Xinxiang-Shangqiu fault has the same location as the artificial seismic profile Geological section has a good correspondence.