Effects of sub-seabed characteristics on acoustic transmission loss in seismic reflection surveys

Abstract

Marine seismic reflection surveys are used to study the composition of the seabed and sub-seabed by recording reflections of the field generated by an airgun array from the seafloor with a towed horizontal streamer. The abundance of data within a single survey and the number of publicly available surveys provides substantial opportunity for data-driven acoustic analysis. Here, we consider data from surveys that were conducted off the coasts of Oregon, Washington, British Columbia, and Alaska, covering portions of the Cascadia Subduction Zone and the Queen Charlotte Fault. Throughout the experiments, data was collected at depths ranging from 200 m to 3 km, typically using a 15 km long towed streamer containing 1200 hydrophone groups with 12.5 m spacing. With these datasets, there is a breadth of opportunity for studying the impacts of various seabed features on acoustic propagation. This talk will explore the impacts of seabed and sub-seabed characteristics, bathymetry, reflectivity, etc., on acoustic transmission loss. The data from these experiments, corrected for array design impacts, will be compared directly with computational propagation models. [Work supported by ONR.]