华北地区地壳上地幔P波速度结构

本文利用近震体波资料,研究了华北地区地壳和上地幔P波速度结构。根据华北地区的大地构造特征,分四个区域研究。结果表明,各区之间P波速度结构存在明显差异,在较活动地区壳内和地幔顶部均有低速层存在,而稳定地区则没有,作者认为,这种横向不均匀性和低速层的存在可能是构造活动区的最主要的特征。

CRUST-UPPER MANTLE P WAVE VELOCITY STRUCTURE BENEATH NORTHERN CHINA

In this paper,the crust and the upper mantle velocity structure beneath northern China has been studied by the use of near-by earthquake P wave information.Based on the regional tectonic feature,the region is divided into four parts.The result show: there are obviously difference among P wave velocity structures beneath every regions,the crust and upper mantle low velocity layer exist in seismically active area and not in steady area.Authors consider that the existence of the lateral hetergoentity of P-wave structure and low velocity layer may be mainest feature of tectonic active area.