摘要
利用穿过张渤地震构造带中西段及邻区的多条地震测深资料,详细研究了张渤地震构造带中西段及邻区的地壳深部速度结构与构造。结果表明,该区地壳深部速度结构与构造在纵向和横向上具有明显的不均一性。在三河-平谷8级震区、延庆-怀来盆地及张家口附近地区莫霍面埋深分别为35、39和42 km,其地壳厚度由东至西逐渐增加。该区基底断裂发育。在其深部,根据地震波动力学及运动学特征和二维速度结构中的地震界面与速度等值线起伏变化推测,在大兴、延庆、涿鹿等地均存在深部断裂带,在深部断裂带一侧或两侧的上地壳存在6.0 km/s左右的低速层(体)。
Deep crust velocity structure and tectonics are studied in detail in the midwest segment and its adjacent region of Zhangjiakou-Bohai seismic zone by use of the data of multiple seismic sounding profiles. The results show strong vertical and lateral inhomogeneity in deep crust velocity structure and tectonics. The depth of Moho discontinuity is 35 km,39 km and 42 km in Sanhe-Pinggu macroquake（Ms=8.0） region,Yanqing-Huailai Basin and Zhangjiakou respectively. The thickness of the crust of this segment increases gradually from east to west. The shallow basement fault has developed. Regarding the character of seismic wave dynamics and activity in depth and the undulation of earthquake interface and velocity isoline in 2-D velocity structure,it is concluded that not only deep crustal fault zone exists in Daxing, Yanqing and Zhuolu but also low-velocity layer（body）（6.0 km/s） exists in the upper crust of one side or both side of deep crustal fault zone.
出处
《大地测量与地球动力学》
CSCD
北大核心
2005年第3期110-115,共6页
Journal of Geodesy and Geodynamics
基金
国家重点自然科学基金(40334040)
中国地震局地球物理勘探中心科技论著Recod200502
关键词
地震测深
地壳
地震界面
速度结构
低速层(体)
seismic sounding, crust, seismic interface, velocity structure, low-velocity layer（body）
