Ambient sound effects and propagation characteristics seismic survey datasets recorded on OOI hydrophones

Marine seismic reflection surveys provide an abundance of acoustic data over survey regions and surrounding areas. The data from these surveys, in addition to passive observations made possible with networks like the Ocean Observatories Initiative (OOI), provide a wealth of acoustic propagation data in a variety of environments. Furthermore, the repeatability of airgun array shots yields a minimally variable source from which to extract more precise trends. In this work, we consider data from two seismic surveys, MGL1905 and MGL2104, during which a 6600 in3 airgun array is fired every 37.5 m along multiple survey lines extending 10s to 100s of kilometers. The data collected on the OOI hydrophones is analyzed to quantify long-term trends in the ambient soundscape. Additionally, characteristics and artifacts in the data are examined for possible usefulness in extracting details about the propagating environment. [Work supported by ONR.]