辽宁地区波速比分布特征及构造意义

Distributions Characteristics of Wave Velocity Ratio and Associated Tectonic Significance in Liaoning Area

摘要:

利用辽宁数字台网2001年以来的观测报告，采用单台和达法计算辽宁测震台网34个台站的平均波速比，重点分析辽宁地区波速比的空间分布特征。结果显示，辽宁地区的波速比空间分布呈横向不均匀性，下辽河盆地的波速比平均值低于整个辽宁地区波速比的均值，而辽西隆起和辽东隆起区的波速比却明显高于下辽河盆地的波速比和辽宁地区的均值。研究也发现，辽宁地区5级以上地震多发生在波速比低值区或高低值过渡区。计算所得的各区平均波速比对以后辽宁地区波速比值的变化分析有一定的参考作用。

Abstract:

Based on the observation data from Liaoning Digital Seismic Network since 2001, we used the Wadati method of single station to calculate the average wave velocity ratio of 34 stations in Liaoning Seismic Network, and focused on the spatial distribution characteristics of wave velocity ratio in Liaoning area. The results showed that the spatial distribution of wave velocity ratio in Liaoning area has laterally heterogeneities. The average wave velocity ratio in Xialiaohe basin is lower than that in the whole Liaoning area, while the wave velocity ratio in western and eastern Liaoning is significantly higher than that in Xialiaohe basin and the average value of Liaoning area. It is also found that M≥5.0 earthquakes in Liaoning area mostly occurred in the low-value zone of wave velocity ratio or the transition area of high to low value. The calculated average wave velocity ratio of each region has a certain reference value for future analysis of wave velocity ratio changes in Liaoning area.