none 10.1190/geo2024-0009.1 Society of Exploration Geophysicists Society of Exploration Geophysicists 186 164051605 5981 2025121212395564100 10.1190 2025-12-12T17:40:06Z 2024-08-28T09:07:14Z 3 Geophysics 0016-8033 1942-2156 01 11 2024 89 6 Alexander S. Douglass University of Washington 1 , School of Oceanography, Seattle, Washington, USA. asd21@uw.edu (corresponding author) http://orcid.org/0000-0001-6778-4207 Shima Abadi University of Washington 1 , School of Oceanography, Seattle, Washington, USA. abadi@uw.edu http://orcid.org/0000-0001-8122-3545 Warren T. Wood U.S. Naval Research Laboratory 2 , Geology and Geophysics, Stennis, Mississippi, USA. warren.wood@nrlssc.navy.mil http://orcid.org/0000-0002-7214-6100 Benjamin J. Phrampus U.S. Naval Research Laboratory 2 , Geology and Geophysics, Stennis, Mississippi, USA. benjamin.phrampus@nrlssc.navy.mil http://orcid.org/0000-0002-6405-3625 ABSTRACT Marine seismic reflection surveys generate high-amplitude impulsive acoustic events using airgun arrays to study the geophysical characteristics of the seabed. These data can be used beyond seismic imaging, including for modeling short-range propagation, considering impacts on marine mammals, and extracting seabed properties and their effect on the acoustic field. Knowledge of the source characteristics is necessary to use these data, and proper modeling of sound propagation from these arrays requires characterization of the array beam pattern. Complex simulations of airgun arrays have been used in the past to model airgun array spectra, but beam patterns have not been thoroughly considered in the literature. Delay-and-sum combinations of these airgun signatures provide a simple beam pattern estimate, but this approach ignores variability in airgun position, timing, amplitude, interactions between airguns, and so on. The use of more complex notional airgun signatures can yield more accurate estimates, but these are more challenging to model and still ignore shot-to-shot variability. Experimentally determined beam patterns are evaluated here, and the variability in the results are considered, showing both similarities and notable differences from simulated results. The experimental results indicate that the source array depth impacts the ghost-free array beam pattern and that variability between shots is enough to significantly alter beam patterns. Overall, the observations suggest that accurate simulation of array beam patterns may require more complexity than is currently considered and that inclusion of uncertainty due to environmental and airgun shot variability is essential. 11 21 2024 01 11 2024 V653 V667 Office of Naval Research http://dx.doi.org/10.13039/100000006 N00014-21-1-2727 http://www.niso.org/schemas/ali/1.0/ 1 10.1190/crossmark-policy library.seg.org true 2024-01-10 2024-08-12 2024-08-17 2024-11-21 Office of Naval Research http://dx.doi.org/10.13039/100000006 N00014-21-1-2727 10.1190/geo2024-0009.1 https://pubs.geoscienceworld.org/geophysics/article/89/6/V653/650286/A-quantitative-analysis-of-acoustic-field https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/89/6/V653/7071531/geo-2024-0009.1.pdf https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/89/6/V653/7071531/geo-2024-0009.1.pdf https://pubs.geoscienceworld.org/geophysics/article/89/6/v653/650286/a-quantitative-analysis-of-acoustic-field 0001-4966 Journal of the Acoustical Society of America Abadi 146 2430 2019 10.1121/1.5127843 Short-range propagation characteristics of airgun pulses during marine seismic reflection surveys 10.23919/OCEANS40490.2019.8962817 Abadi S. 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