Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements
Bottom-loss measurements were made for frequencies less than 800 Hz at three stations in the Hatteras Abyssal Plain. The stations were each separated approximately 55 km along 70 deg. 30'W longitude. The data acquisition procedure was to launch two self-recording submersibles (AUTOBUOYS) and th...
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ftdtic:ADA070267 2023-05-15T17:35:00+02:00 Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements Herstein, Peter D. Dullea, Robert K. Santaniello, Salvatore R. NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB 1979-04-14 text/html http://www.dtic.mil/docs/citations/ADA070267 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA070267 en eng http://www.dtic.mil/docs/citations/ADA070267 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Acoustic Detection and Detectors Acoustics *UNDERWATER SOUND SIGNALS *BOTTOM LOSS ACOUSTIC MEASUREMENT UNDERWATER EXPLOSIONS UNDERWATER ACOUSTICS NORTH ATLANTIC OCEAN ABYSSAL ZONES SEDIMENTS LOW FREQUENCY OCEAN BOTTOM SOILS SONOBUOYS ACOUSTIC REFLECTION ACOUSTIC REFRACTION Hatteras Abyssal Plain PE62759N WU19345 LPN-NUSC-A-650-06 Text 1979 ftdtic 2016-02-20T16:10:58Z Bottom-loss measurements were made for frequencies less than 800 Hz at three stations in the Hatteras Abyssal Plain. The stations were each separated approximately 55 km along 70 deg. 30'W longitude. The data acquisition procedure was to launch two self-recording submersibles (AUTOBUOYS) and then maneuever from and to the launch site detonating explosives as the AUTOBUOYS recorded data. Because of the experimental geometry, the direct and bottom-interacting signals were time-separated as they arrived at the AUTOBUOYS. Thus, a 'self-calibrating' processing procedure could be used to compute bottom loss values. Bottom loss versus grazing angles (5-66 deg) was obtained over a wide bandwidth (90-790 Hz) and for a number of narrow bandwidths (1/3 octave and less). Broadband results were found to be homologous between stations, whereas the narrowband results were less correlated. Negative bottom loss values were also observed. Analyses of the impulse responses for the southern station also aided in developing a geophysical description of the sediment structure. The derived structure consists of a thin (21 m), constant sound-speed layer overlaying a thick layer having a linear depth-dependent sound speed. This structure is representative of a class of documented subbottom sediment structures that can support the propagation of low-frequency acoustic signals traversing non-plane wave reflected and refracted acoustic paths. Text North Atlantic Defense Technical Information Center: DTIC Technical Reports database |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Acoustic Detection and Detectors Acoustics *UNDERWATER SOUND SIGNALS *BOTTOM LOSS ACOUSTIC MEASUREMENT UNDERWATER EXPLOSIONS UNDERWATER ACOUSTICS NORTH ATLANTIC OCEAN ABYSSAL ZONES SEDIMENTS LOW FREQUENCY OCEAN BOTTOM SOILS SONOBUOYS ACOUSTIC REFLECTION ACOUSTIC REFRACTION Hatteras Abyssal Plain PE62759N WU19345 LPN-NUSC-A-650-06 |
spellingShingle |
Acoustic Detection and Detectors Acoustics *UNDERWATER SOUND SIGNALS *BOTTOM LOSS ACOUSTIC MEASUREMENT UNDERWATER EXPLOSIONS UNDERWATER ACOUSTICS NORTH ATLANTIC OCEAN ABYSSAL ZONES SEDIMENTS LOW FREQUENCY OCEAN BOTTOM SOILS SONOBUOYS ACOUSTIC REFLECTION ACOUSTIC REFRACTION Hatteras Abyssal Plain PE62759N WU19345 LPN-NUSC-A-650-06 Herstein, Peter D. Dullea, Robert K. Santaniello, Salvatore R. Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
topic_facet |
Acoustic Detection and Detectors Acoustics *UNDERWATER SOUND SIGNALS *BOTTOM LOSS ACOUSTIC MEASUREMENT UNDERWATER EXPLOSIONS UNDERWATER ACOUSTICS NORTH ATLANTIC OCEAN ABYSSAL ZONES SEDIMENTS LOW FREQUENCY OCEAN BOTTOM SOILS SONOBUOYS ACOUSTIC REFLECTION ACOUSTIC REFRACTION Hatteras Abyssal Plain PE62759N WU19345 LPN-NUSC-A-650-06 |
description |
Bottom-loss measurements were made for frequencies less than 800 Hz at three stations in the Hatteras Abyssal Plain. The stations were each separated approximately 55 km along 70 deg. 30'W longitude. The data acquisition procedure was to launch two self-recording submersibles (AUTOBUOYS) and then maneuever from and to the launch site detonating explosives as the AUTOBUOYS recorded data. Because of the experimental geometry, the direct and bottom-interacting signals were time-separated as they arrived at the AUTOBUOYS. Thus, a 'self-calibrating' processing procedure could be used to compute bottom loss values. Bottom loss versus grazing angles (5-66 deg) was obtained over a wide bandwidth (90-790 Hz) and for a number of narrow bandwidths (1/3 octave and less). Broadband results were found to be homologous between stations, whereas the narrowband results were less correlated. Negative bottom loss values were also observed. Analyses of the impulse responses for the southern station also aided in developing a geophysical description of the sediment structure. The derived structure consists of a thin (21 m), constant sound-speed layer overlaying a thick layer having a linear depth-dependent sound speed. This structure is representative of a class of documented subbottom sediment structures that can support the propagation of low-frequency acoustic signals traversing non-plane wave reflected and refracted acoustic paths. |
author2 |
NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB |
format |
Text |
author |
Herstein, Peter D. Dullea, Robert K. Santaniello, Salvatore R. |
author_facet |
Herstein, Peter D. Dullea, Robert K. Santaniello, Salvatore R. |
author_sort |
Herstein, Peter D. |
title |
Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
title_short |
Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
title_full |
Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
title_fullStr |
Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
title_full_unstemmed |
Hatteras Abyssal Plain Low Frequency Bottom Loss Measurements |
title_sort |
hatteras abyssal plain low frequency bottom loss measurements |
publishDate |
1979 |
url |
http://www.dtic.mil/docs/citations/ADA070267 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA070267 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA070267 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766134004686258176 |