EXPERIMENTAL ANALYSIS OF BOTTOM-SEISMIC AND HYDROACOUSTIC SIGNALS GENERATED BY RIVER BOATS

摘要

Hydroacoustic and bottom-seismic signals generated by river motor boats moving along the river are recorded experimentally. Hydroacoustic signals are recorded in water at a distance of several meters from the river bank, whereas bottom-seismic signals are recorded close to the water boundary where dry sand is the natural continuation of the river bottom. Main attention is paid to analysis of seismic oscillations, since hydroacoustic noise caused by a river boat has been actively discussed in literature. Several spectra of bottom-seismic and hydroacoustic signals of a moving boat are presented to illustrate the report. Absolute values of principal components of the spectra and the general level of bottom-seismic signals recorded at distances less than the first hundreds of meters from the source are measured. The spectral peculiarities have demonstrated principal distinctions between seismic and hydroacoustic signals. Models of seismo-acoustic field radiation in several spectral windows, based on the analysis of the obtained spectral characteristics, are proposed. Data of the analysis can be of interest in study of physical mechanisms of noise caused by river navigation. They can be also useful for the development and improvement of environmental monitoring methods and for control of ecological situation near rivers.