新英格兰泥上的地声学属性的深度和频率取决于反射系数的反转)
Yong-Min Jiang1, Charles W Holland2, Stan E Dosso1
1School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada.
The Journal of the Acoustical Society of America
|October 18, 2023
概括
这项研究使用先进的声学数据对新英格兰泥 (NEMP) 的泥沉积物结构进行了建模. 发现揭示了不同的层,其属性随着深度的变化而变化,这对于了解大陆架环境至关重要.
科学领域:
- 海洋地质物理学 海洋地质物理学
- 声学沉积物的特征描述.
- 大陆架的过程大陆架的过程.
背景情况:
- 泥沉积物在大陆架上广泛存在,但特征不佳.
- 了解沉积物的物理性质对于海洋地球物理学和声学建模至关重要.
研究的目的:
- 在新英格兰泥 (NEMP) 上开发沉积物柱结构和变异性的一般模型.
- 通过使用先进的反射系数反转来提高地声学分析的分辨率并减少不确定性.
主要方法:
- 广角,宽带反射系数数据的跨维贝叶斯反转.
- 分析高频,更大的带宽数据,涵盖较低的牧场角度.
- 整合新数据与两个之前的NEMP反射系数反转.
主要成果:
- 建立了一个一般的沉积物柱模型,包括一个上层泥层,一个中间均的泥层和一个过渡层.
- 过渡层显示了由于沙子含量增加而发生的快速性质变化 (孔径减少,声速增加,密度和衰减).
- 在整个400-3125Hz频段的泥土中没有观察到有意义的声速分散.
- 沉积物衰减呈现出大约线性频率依赖.
结论:
- 开发的模型为了解NEMP上的泥沉积物结构提供了一个强大的框架.
- 泥沉积物的地声学特性通过应用的反转技术得到了很好的解决.
- 这些发现有助于更好地了解泥海洋环境中的声波传播.
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