Citation

Prior MK, Zampolli M, Heaney K. J. Acoust. Soc. Am. 2013; 134(5): 4000.

Affiliation

PTS, Comprehensive Nuclear-Test-Ban Treaty Organisation, PO Box 1200, Vienna 1400, Austriamark.prior@ctbto.org.

Copyright

(Copyright © 2013, American Institute of Physics)

DOI

10.1121/1.4830593

PMID

24180999

Abstract

Ascension Island in the Atlantic Ocean is the site of one of the hydrophone stations that make up part of the hydroacoustic network operated by the Comprehensive Nuclear-Test-Ban Treaty Organization. Hydrophones are deployed in two groups of three, known as triads; one to the north of the island and one to the south. Correlation processing across hydrophones allows signal azimuths to be determined and both triads show large numbers of signals arriving from the south-west. These signals are generated by earthquakes in the region between Fiji and Tonga in the Pacific Ocean and travel through Drake Passage between Antarctica and South America. Signal azimuths are studied and it is shown that some signals originate from earthquakes to which two-dimensional propagation modeling would suggest there is no direct path. The mechanisms by which sound from these "blocked" regions might reach Ascension Island are discussed.

Language: en