Generally speaking, the characteristics of ground motion can be described by its three elements, namely, the amplitude of ground motion, spectrum and duration.

一般認為，對工程抗震而言，地震動的特性可以通過其三要素來描述，即地震動的振幅，頻譜和持時。

The soil in a sediment basin near ground surface is soft. It has a remarkable amplification and filtering effects on earthquake wave and can change the characters of the amplitude and spectrum of ground motion wave significantly.

大型沉積盆地中，近地表土層比較松軟，對地震波有明顯的放大和濾波的作用，可以顯著改變地震動的幅值和頻譜特征。

Study on random fluctuation characteristics of amplitude spectra of strong ground motion

強地震動幅值譜隨機漲落特征的研究