As a result , the low - frequency contents increase as the centroid of signal spectrum experiences a downshift , in case that frequency is independent on quality factor , the offset of the centroid frequency is proportional to the integral of attenuation factor along wavepath , thus can he used to reconstruct the attenuation distribution 假設(shè)介質(zhì)的品質(zhì)因子與頻率無關(guān),地震波主頻的偏移量與吸收系數(shù)對(duì)傳播路徑的積分成比例,則通過它們之間的關(guān)系可以估測介質(zhì)的吸收系數(shù)。