不同台阵形式对微动探测结果的影响

在江汉盆地的同一场地分别采用三重圆形、T形及L形3种不同台阵形式进行微动探测观测对比实验,结果表明,3种台阵形式提取到的频散曲线基本一致,但频散图谱能量集中度具有明显的差异。三重圆形台阵频散图谱能量集中度最高,L形、T形台阵在2.0~4.6 Hz频段范围内集中度较高,而在1.2~2.0 Hz频段范围内较分散;相比T形和L形台阵,三重圆形台阵更易于探测到地层分界面附近的波速突变特征,即三重圆形台阵比其他两种台阵形式准确性及可靠性更高。

Influence of Different Array Type on the Results of Microtremor Survey

In the same site of Jianghan basin, three different array forms: triple circular, T-shaped and L-shaped, are used for observation and comparison experiments. The results show that the dispersion curves of the three arrays are basically the same; the energy concentration degree of the three arrays is obviously different. The energy concentration degree of the triple circular arrays is the highest, and the concentration degree of the L-shaped and T-shaped arrays is also higher in the range of 2.0-4.6 Hz. Compared with the T-shaped and L-shaped arrays, the wave velocity contrast of the triple circular arrays near the stratigraphic interface is more obvious; that is, the triple circular arrays is more reliable and accurate than the other two array forms.