Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Diversity of Protists III01:27

Diversity of Protists III

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,...
Deep Sea Microbial Ecology01:18

Deep Sea Microbial Ecology

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 extending beyond...
Marine Microbial Ecology01:30

Marine Microbial Ecology

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...
Other Algae01:19

Other Algae

The group Stramenopiles include some phototrophic microorganisms. Members of this group possess flagella covered in numerous short, hairlike extensions, a feature that inspired the group's name, derived from the Latin words for "straw" and "hair." Some of the main categories of Stramenopiles include diatoms, golden algae, and brown algae.Diatoms are unicellular, photosynthetic eukaryotes, with over 200 known genera. They play a key role in the planktonic communities of both marine and...
Microbial Mats01:25

Microbial Mats

Microbial communities forming biofilms and mats represent complex, spatially structured ecosystems where metabolic processes are stratified according to light, oxygen, and nutrient gradients. Biofilms are initial colonization stages, only a few millimeters thick, while mature microbial mats can reach centimeter-scale thickness and display intricate vertical organization. Their structural and functional heterogeneity allows microorganisms to occupy distinct ecological niches within a few...
Deleterious Substances in Aggregate01:25

Deleterious Substances in Aggregate

Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Mud sound speed profile constraints from sub-bottom arrival times.

JASA express letters·2026
Same author

Phase of the seabed frequency-domain reflection coefficient: Measurements and modelinga).

JASA express letters·2025
Same author

Erratum: Sediment interval velocities from a monostatic multibeam sonar [J. Acoust. Soc. Am. 147, EL13-EL18 (2020)].

The Journal of the Acoustical Society of America·2024
Same author

Depth and frequency dependence of geoacoustic properties on the New England Mud Patch from reflection coefficient inversiona).

The Journal of the Acoustical Society of America·2023
Same author

Sound speed gradients in mud.

JASA express letters·2022
Same author

Hamilton's geoacoustic model.

The Journal of the Acoustical Society of America·2022
Same journal

High-resolution depth estimation for multiple wideband sources in deep sea via sparse Bayesian learninga).

The Journal of the Acoustical Society of America·2026
Same journal

Depression markers in speech: An approach based on tract variables dynamics.

The Journal of the Acoustical Society of America·2026
Same journal

The oyster toadfish (Opsanus tau) alters active and diurnal calling amid vessel noise in New York City.

The Journal of the Acoustical Society of America·2026
Same journal

Experimental noise characterisation of phase-locked tandem-rotor in edgewise flight.

The Journal of the Acoustical Society of America·2026
Same journal

The tune-text-temporal synergy: Prosodic effects of final segmental weakening in Neapolitan.

The Journal of the Acoustical Society of America·2026
Same journal

Monitoring vessel movement above critical offshore infrastructure using distributed acoustic sensing.

The Journal of the Acoustical Society of America·2026
See all related articles

Related Experiment Video

Updated: May 21, 2026

Data Collection on Marine Litter Ingestion in Sea Turtles and Thresholds for Good Environmental Status
13:18

Data Collection on Marine Litter Ingestion in Sea Turtles and Thresholds for Good Environmental Status

Published on: May 18, 2019

Clutter from non-discrete seabed structures.

Charles W Holland1, Dale D Ellis

  • 1Applied Research Laboratory, The Pennsylvania State University, State College, Pennsylvania 16804, USA. cwh10@psu.edu

The Journal of the Acoustical Society of America
|June 21, 2012
PubMed
Summary
This summary is machine-generated.

Active sonar faces clutter challenges from discrete objects. This study reveals that slowly varying seabed structures can also cause target-like returns, offering a new explanation for observed seabed clutter.

More Related Videos

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles
09:01

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

Published on: April 19, 2018

Reefshape: A System for the Efficient Collection and Automated Processing of Time-Series Underwater Photogrammetry Data for Benthic Habitat Monitoring
13:35

Reefshape: A System for the Efficient Collection and Automated Processing of Time-Series Underwater Photogrammetry Data for Benthic Habitat Monitoring

Published on: June 13, 2025

Related Experiment Videos

Last Updated: May 21, 2026

Data Collection on Marine Litter Ingestion in Sea Turtles and Thresholds for Good Environmental Status
13:18

Data Collection on Marine Litter Ingestion in Sea Turtles and Thresholds for Good Environmental Status

Published on: May 18, 2019

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles
09:01

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

Published on: April 19, 2018

Reefshape: A System for the Efficient Collection and Automated Processing of Time-Series Underwater Photogrammetry Data for Benthic Habitat Monitoring
13:35

Reefshape: A System for the Efficient Collection and Automated Processing of Time-Series Underwater Photogrammetry Data for Benthic Habitat Monitoring

Published on: June 13, 2025

Area of Science:

  • Ocean acoustics
  • Sonar signal processing

Background:

  • Clutter, or discrete target-like returns, is a significant problem in active sonar.
  • Discrete objects with significant impedance contrast cause clutter.

Purpose of the Study:

  • Investigate a counter-intuitive source of sonar clutter: slowly varying seabed structures.
  • Hypothesize a new mechanism for seabed clutter in the absence of discrete features.

Main Methods:

  • Analysis of sonar returns from seabed structures with weak and smooth range dependence.
  • Utilizing broadband sonar sources to study time-frequency evolution of clutter.

Main Results:

  • Demonstrated that slowly varying seabed structures can generate discrete target-like returns.
  • Showcased that range dependence due to changes in layer thickness or sound speed can cause clutter.
  • Identified time-frequency evolution as a method to discriminate this clutter from other types.

Conclusions:

  • Slowly varying seabed structures present a viable hypothesis for observed seabed clutter.
  • Broadband sonar analysis can differentiate seabed clutter from discrete object clutter.