Frequency dependence of sound speed and attenuation in fine-grained sediments from 25 to 250 kHz based on a probe method
Frequency dependence of sound speed and attenuation in fine-grained sediments from 25 to 250 kHz based on a probe method
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基于探针法的 25 至 250kHz 细粒沉积物中声速和衰减的频率依赖性
DOI：
10.1016/j.oceaneng.2018.04.078
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发表时间：
2018
影响因子：
5
通讯作者：
Xiangmei Meng
中科院分区：
文献类型：
--
作者：
Jingqiang Wang;Baohua Liu;Guangming Kan;Guanbao Li;Jiewen Zheng;Xiangmei Meng
在实验室中，使用探头法在25-250 kHz的频率范围内测量了海底沉积物中声速和衰减的频率依赖性。在淡水中重复测量声速的标准偏差约为2.82m/s。衰减的重复测量显示在25 kHz时的最小标准偏差为0.58 dB，在250 kHz时的最大标准偏差为3.06 dB/m。测量结果表明，在桑迪粉砂沉积物中声速变化范围为1638 ~ 1658 m/s，在粘土质粉砂沉积物中声速变化范围为1548 ~ 1571 m/s。在桑迪粉砂沉积物中，衰减从14.2增加到51.9 dB/m，在粘土质粉砂沉积物中，衰减从7.8增加到31.7 dB/m。在桑迪粉质沉积物中测量的声速频散与Biot-Stoll模型、颗粒剪切模型和有效密度流体模型（EDFM）的预测结果基本一致。与Biot-Stoll模型和EDFM模型相比，GS模型的预测结果与实测值吻合较好。测量的衰减与f1/2相关性比f1相关性更一致，与Biot-Stoll模型和EDFM的预测结果相似。
The frequency dependence of the sound speed and attenuation in seafloor sediments was measured in a laboratory by using a probe method at the frequency range of 25–250 kHz. The standard deviation of repeated sound speed measurement in fresh water is about 2.82 m/s. Repeated measurement of attenuation shows a minimum standard deviation of 0.58 dB at 25 kHz and a maximum standard deviation of 3.06 dB/m at 250 kHz. The measurement results indicate that the sound speeds vary from 1638 to 1658 m/s in sandy silt sediments and from 1548 to 1571 m/s in clayey silt sediments. The attenuation increases from 14.2 to 51.9 dB/m in sandy silt sediments and from 7.8 to 31.7 dB/m in clayey silt sediments. The measured sound speed dispersion in sandy silt sediment agrees reasonably with the predictions of the Biot-Stoll model, the Grain-Shearing model, and the Effective Density Fluid model (EDFM). The measured sound speed in clayey silt sediment agrees better with the predictions of the GS model than that of the Biot-Stoll model and the EDFM. The measured attenuation is more consistent with f1/2dependence than the f1dependence, and is similar to the predictions of Biot-Stoll model and the EDFM.