Experimental determination of the three-dimensional primary field of a seismic airgun array.

Abstract

The Littoral Acoustic Demonstration Center (LADC) recorded acoustic and related data on three moored arrays and ship-deployed hydrophones, which together spanned the full water column to measure the 3-D acoustic field of a seismic airgun array, in September 2007. The seismic source vessel shot specified lines to give detailed solid angle and range information concerning the field of the primary arrival. The data were collected in the western Gulf of Mexico between the East Break and Alamos Canyon regions. Peak pressures, sound exposure levels, total shot energy spectra, one-third octave band analyzes, and source directivity studies are used to characterize the field. Three-dimensional maps of these quantities are generated to show dependence on emission and azimuthal angles and range. Longer lines were shot for propagation analyzes. Source signatures from NUCLEUS and GUNDALF are used in propagation modeling. [Research supported by the Joint Industry Programme through the International Association of Oil and Gas Producers.]