Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring
An experimental marine seismic source survey off the northwest Australian coast operated a 2600 cubic inch (41.6 l) airgun array, every 5.88 s, along six lines at a northern site and eight lines at a southern site. The airgun array was discharged 27,770 times with 128,313 pressure signals, 38,907 th...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-05-01
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| Series: | Journal of Marine Science and Engineering |
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| Online Access: | https://www.mdpi.com/2077-1312/9/6/571 |
| _version_ | 1797532762736951296 |
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| author | Robert D. McCauley Mark G. Meekan Miles J. G. Parsons |
| author_facet | Robert D. McCauley Mark G. Meekan Miles J. G. Parsons |
| author_sort | Robert D. McCauley |
| collection | DOAJ |
| description | An experimental marine seismic source survey off the northwest Australian coast operated a 2600 cubic inch (41.6 l) airgun array, every 5.88 s, along six lines at a northern site and eight lines at a southern site. The airgun array was discharged 27,770 times with 128,313 pressure signals, 38,907 three-axis particle motion signals, and 17,832 ground motion signals recorded. Pressure and ground motion were accurately measured at horizontal ranges from 12 m. Particle motion signals saturated out to 1500 m horizontal range (50% of signals saturated at 230 and 590 m at the northern and southern sites, respectively). For unsaturated signals, sound exposure levels (SEL) correlated with measures of sound pressure level and water particle acceleration (<i>r</i><sup>2</sup><i>=</i> 0.88 to 0.95 at northern site and 0.97 at southern) and ground acceleration (<i>r</i><sup>2</sup><i>=</i> 0.60 and 0.87, northern and southern sites, respectively). The effective array source level was modelled at 247 dB re 1µPa m peak-to-peak, 231 dB re 1 µPa<sup>2</sup> m mean-square, and 228 dB re 1 µPa<sup>2</sup>∙m<sup>2</sup> s SEL at 15° below the horizontal. Propagation loss ranged from −29 to −30log<sub>10</sub> (<i>range</i>) at the northern site and −29 to −38log<sub>10</sub>(<i>range</i>) at the southern site, for pressure measures. These high propagation losses are due to near-surface limestone in the seabed of the North West Shelf. |
| first_indexed | 2024-03-10T11:03:56Z |
| format | Article |
| id | doaj.art-ea01fd47af894f869463d554122ab392 |
| institution | Directory Open Access Journal |
| issn | 2077-1312 |
| language | English |
| last_indexed | 2024-03-10T11:03:56Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Marine Science and Engineering |
| spelling | doaj.art-ea01fd47af894f869463d554122ab3922023-11-21T21:19:43ZengMDPI AGJournal of Marine Science and Engineering2077-13122021-05-019657110.3390/jmse9060571Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental MonitoringRobert D. McCauley0Mark G. Meekan1Miles J. G. Parsons2Centre for Marine Science and Technology, Curtin University, Bentley, WA 6102, AustraliaAustralian Institute of Marine Science, Perth, WA 6009, AustraliaAustralian Institute of Marine Science, Perth, WA 6009, AustraliaAn experimental marine seismic source survey off the northwest Australian coast operated a 2600 cubic inch (41.6 l) airgun array, every 5.88 s, along six lines at a northern site and eight lines at a southern site. The airgun array was discharged 27,770 times with 128,313 pressure signals, 38,907 three-axis particle motion signals, and 17,832 ground motion signals recorded. Pressure and ground motion were accurately measured at horizontal ranges from 12 m. Particle motion signals saturated out to 1500 m horizontal range (50% of signals saturated at 230 and 590 m at the northern and southern sites, respectively). For unsaturated signals, sound exposure levels (SEL) correlated with measures of sound pressure level and water particle acceleration (<i>r</i><sup>2</sup><i>=</i> 0.88 to 0.95 at northern site and 0.97 at southern) and ground acceleration (<i>r</i><sup>2</sup><i>=</i> 0.60 and 0.87, northern and southern sites, respectively). The effective array source level was modelled at 247 dB re 1µPa m peak-to-peak, 231 dB re 1 µPa<sup>2</sup> m mean-square, and 228 dB re 1 µPa<sup>2</sup>∙m<sup>2</sup> s SEL at 15° below the horizontal. Propagation loss ranged from −29 to −30log<sub>10</sub> (<i>range</i>) at the northern site and −29 to −38log<sub>10</sub>(<i>range</i>) at the southern site, for pressure measures. These high propagation losses are due to near-surface limestone in the seabed of the North West Shelf.https://www.mdpi.com/2077-1312/9/6/571seismic airgun sourceparticle motionground motionpropagation loss |
| spellingShingle | Robert D. McCauley Mark G. Meekan Miles J. G. Parsons Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring Journal of Marine Science and Engineering seismic airgun source particle motion ground motion propagation loss |
| title | Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring |
| title_full | Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring |
| title_fullStr | Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring |
| title_full_unstemmed | Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring |
| title_short | Acoustic Pressure, Particle Motion, and Induced Ground Motion Signals from a Commercial Seismic Survey Array and Potential Implications for Environmental Monitoring |
| title_sort | acoustic pressure particle motion and induced ground motion signals from a commercial seismic survey array and potential implications for environmental monitoring |
| topic | seismic airgun source particle motion ground motion propagation loss |
| url | https://www.mdpi.com/2077-1312/9/6/571 |
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