Acoustic Profiling of Fine Suspension Concentration in the Changjiang Estuary

Vertical profiles of suspended fine sediment concentration, tidal current velocity, and salinity were measured in May 1994 in the Changjiang Estuary. High resolution concentration profiles were obtained by using a 0.5-MHz acoustic suspended sediment monitor. High temporal and spatial resolution acou...

Full description

Saved in:
Bibliographic Details
Published in:Estuaries 1999-09, Vol.22 (3), p.648-656
Main Authors: Shi, Z., Ren, L. F., Hamilton, L. J.
Format: Article
Language:English
Subjects:
Acoustic images
Acoustics
Biogeochemistry
Brackish
Chemical suspensions
China, People's Rep., Changjiang Estuary
Current velocity
Earth sciences
Earth, ocean, space
Entrainment
Estuaries
Estuarine dynamics
Exact sciences and technology
Frequency
Geology
High frequency
Marine and continental quaternary
Mud
Ocean tides
Profiling
Reentrainment
Resolution
Resuspension
Salinity
Salinity effects
Sand
Sediment
Sediment concentration
Sediment transport
Sediments
Shear flow
Spatial discrimination
Spatial resolution
Surficial geology
Suspended sediments
Suspended solids
Suspension
Tidal currents
Turbulent shear flow
Velocity
Vertical profiles
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Vertical profiles of suspended fine sediment concentration, tidal current velocity, and salinity were measured in May 1994 in the Changjiang Estuary. High resolution concentration profiles were obtained by using a 0.5-MHz acoustic suspended sediment monitor. High temporal and spatial resolution acoustic profiling of fine suspension concentration provides both the instantaneous vertical profile of concentration and information on the continuous dynamic processes of fine sediment erosion, transport, and deposition. Calibrated acoustic images revealed 1) highly stratified suspensions, 2) resuspension of the cohesive mud bed, and 3) re-entrainment of the near-bed high concentration suspensions by turbulent shear flow. Within the near-bed high concentration suspensions, two different frequencies of highly episodic resuspension processes were identified: high frequency resuspension, lasting a few seconds; low frequency resuspension, lasting a few minutes. The highest concentrations, associated with low velocity and high salinity, were found close to the cohesive mud bed. Lutoclines were persistent features during the measurements.
ISSN:0160-8347
1559-2723
1559-2758
1559-2731
DOI:10.2307/1353052