在薄弱剪切刚度的多层海底上,水下声音的传播)
1Department of Physics, Naval Postgraduate School, 833 Dyer Road, Monterey, California 93943-5216, USA.
The Journal of the Acoustical Society of America
|January 17, 2025
概括
海底沉积物中的薄弱剪切刚性显著影响声学正常模式,导致快速的声音衰减和速度变化. 这些效应对于了解水下声音传播至关重要,并且可以与其他衰减源区分开来.
科学领域:
- 地质物理学 地质物理学
- 声学 声学 在声学方面
- 地震学 地震学
背景情况:
- 声学正常模式透到海底的上层,那里的剪波速度很低.
- 沉积物具有弱但有限的剪切刚性,导致界面上的压缩到剪切波转换.
研究的目的:
- 调查弱剪硬度对海底沉积物中的声学正常模式的影响.
- 分析剪切波生成,干扰及其对声音传播的影响.
主要方法:
- 在海洋沉积物中的声波传播的理论分析.
- 正常模式阶段和组速度的建模.
- 检查声衰减和旅行时间扰动.
主要成果:
- 薄弱的剪切刚性会在正常模式阶段和组速度中造成显著的干扰,即使在非常低的剪切速度下也是如此.
- 沉积层内的剪切波干扰导致频率依赖的声音衰减.
- 在不均的海洋中,通过弱切削而放大了形正常模式的水平折射.
结论:
- 薄弱的剪切刚性极大地影响水下声学,影响声速和减弱.
- 同时测量正常和侧面波衰减可以区分剪切波效应和消散.
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