深沉积物异质性是使用商船的非常低频特征推断出来的 (sa)
Alexandra M Hopps-McDaniel1, Tracianne B Neilsen1, D P Knobles2
1Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.
The Journal of the Acoustical Society of America
|October 8, 2024
概括
船舶噪音揭示了深海底的特性. 在船舶光谱图中分析独特的声学特征有助于估计新英格兰泥的深层声音速度和厚度.
科学领域:
- 海洋声学 海洋声学
- 处理地震信号的地震信号处理.
- 海洋地质物理学 海洋地质物理学
背景情况:
- 商船噪声为研究深海底层提供了有价值的宽带声源.
- 船舶光谱图显示嵌套的条纹,声学特征与波导不变 (β) 变得无限相关.
研究的目的:
- 在船舶噪声谱图中识别β = ∞频率.
- 为了在新英格兰泥中对深层声音速度和厚度进行统计推断.
- 扩大之前的研究,包括更多的船只,声波阵列和更大的地理区域.
主要方法:
- 在船舶噪声时间频谱图中识别单一点 (β = ∞频率).
- 基于特征的反转使用这些奇点来估计海底声学特性.
- 深层声速和船舶轨道的空间变化之间的相关性分析,以检查异质性.
主要成果:
- 在2080赫兹频率范围内发现了奇点.
- 基于特征的反转提供了声速的估计值和第一个深层厚度的极限值.
- 研究了与船舶轨迹相关的深层声速的空间变化.
结论:
- 这项研究成功地利用船舶噪声特征推断深海底的声学特性.
- 该方法提供声速和层厚度的估计,具有异质性分析的潜力.
- 这种方法提供了一种可扩展的方法,用于使用环境噪声源进行海底表征.
相关概念视频
Gravimetry: Overview
11.9K
Gravimetric analysis is a quantitative method where the analyte is isolated and weighed directly or after conversion into a substance of known composition. Gravimetric analysis can be classified as precipitation, electrogravimetry, volatilization, and particulate gravimetry, based on the method used to isolate the analyte.
In precipitation gravimetry, the analyte is converted into a precipitate and weighed. For example, the silver content in a sample can be estimated by precipitating and...
In precipitation gravimetry, the analyte is converted into a precipitate and weighed. For example, the silver content in a sample can be estimated by precipitating and...
11.9K
Precipitation Gravimetry
12.8K
Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
12.8K
Uniform Depth Channel Flow
876
Uniform depth channel flow keeps fluid depth consistent along channels such as irrigation canals. In natural channels, such as rivers, approximate uniform flow is often assumed. This condition occurs when the channel’s bottom slope matches the energy slope, balancing potential energy lost from gravity with head loss due to shear stress. This balance prevents depth changes along the channel length, resulting in a steady, uniform flow.Uniform flow in open channels with a constant...
876
Diversity of Protists III
2.1K
Rhizaria are a diverse group of unicellular protists characterized by their threadlike cytoplasmic extensions known as pseudopodia. These structures aid in both locomotion and feeding, giving Rhizaria an amoeboid appearance. Their amoeboid morphology once led to taxonomic confusion, but molecular phylogenetics has clarified their evolutionary placement and emphasized their shared use of pseudopodia despite divergent lineages.This clade comprises diverse lineages such as Chlorarachniophyta,...
2.1K
Marine Microbial Ecology
66
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...
66
Deep Sea Microbial Ecology
53
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches...
53


