Geoacoustic inversion using air gun sounds measured by a single hydrophone in the East Siberian Sea

Abstract

Korea Polar Research Institute had operated after installing a bottom-moored single hydrophone in the East Siberian continental margin in the Arctic Ocean for about one year from August 2019 for long-term underwater noise monitoring. In addition, a seismic survey using an air gun was conducted in September 2019, and the air gun sounds were received by the hydrophone. The modal dispersion curves were observed in the result of spectrogram analysis of the air-gun signals received at distances of several tens of km between the sound source and the hydrophone. We extracted the dispersion curves from the spectrogram using a time-warping signal processing. Inversion of geoacoustic parameters such as sound speed and density in the sediment layer was carried out by minimizing the mismatch between extracted dispersion curves and the replicas predicted by the KRAKEN normal-mode propagation program. The results will be discussed through comparison with the sedimentary environment of the East Siberian Sea. © ICA 2022.All rights reserved