来自海洋沉积物的平面波和圆柱形波声反射,其分层代表新英格兰泥的代表性
1Marine Physical Laboratory, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0238, USA.
The Journal of the Acoustical Society of America
|September 17, 2024
概括
这项研究分析了海洋沉积物的声音反射,发现减弱产生了依赖源高度而不是频率的准临界角度. 这种行为与新英格兰泥的实验观测结果相符.
科学领域:
- 声学 声学 在声学方面
- 海洋地质物理学 海洋地质物理学
- 沉积物物理 沉积物物理
背景情况:
- 海洋沉积物层,如新英格兰泥 (NEMP) 的海洋沉积物层,通常具有复杂的声学特性.
- 了解这些层的声音反射对于地质调查和水下声学至关重要.
研究的目的:
- 分析来自特定海洋沉积物结构的声音反射:沙泥地下室上的泥层,带有声速梯度.
- 开发反射系数的理论模型,并与实验数据进行比较.
主要方法:
- 应用海和沉积层的海尔姆霍尔茨方程的积分变换.
- 导出了圆柱形波反射系数的波数积分.
- 使用静止相评估来获得平面波反射系数.
主要成果:
- 平面波溶液显示总反射到一个临界角度,没有衰减.
- 衰减引入了反射系数的峰值,而不是总反射.
- 圆柱形波溶液表现出一个近临界的角度,取决于源接收器高度和泥层深度,但不是频率.
结论:
- 理论模型准确地预测了海洋沉积物的声学反射行为.
- 这些发现解释了新英格兰泥地区关于准临界角度的实验观测.
- 沉积物衰减显著影响水下声学反射模式.
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