Abstract: We have performed 2D processing, calculations and interpretation of the seismic sounding data of a wide-angle reflection and refraction profile from Xiji to Zhongwei. Our purpose is to study the velocity structure of the crust and upper mantle around the arc-shape tectonics near Zhongning, Zhongwei and Tongxin, Ningxia. The results show that the velocity structure of the crust and upper mantle of this region is remarkably not homogeneous. The crustal thickness has big variations. The Moho interface is relatively shallow at the middle of the arc-shape tectonic zone and becomes deeper at the other places.

Key words: Seismic sounding, Velocity structure, Structure of crust and mantle, Xiji—Zhongwei

摘要： 通过对南北向的西吉—中卫宽角反射/折射剖面测深资料的二维处理、计算和解释,研究了中宁、中卫和同心一带弧形构造及其两侧的壳幔速度结构和深部构造的基本特征。结果表明,3个区域的壳幔速度结构在纵向和横向上均具有明显的非均匀性,标志壳幔深部构造存在着差异,地壳厚度变化大,弧形构造带中部为一莫霍面隆起(深45.0km),弧形构造带南北两侧上地壳中存在不同的低速块体。

关键词: 地震测深, 速度结构, 壳幔构造, 西吉—中卫