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Underwater Sound Measurements During 3D Seismic Acquisition in Shallow Water, Dutch Southern North Sea
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 79th EAGE Conference and Exhibition 2017, Jun 2017, Volume 2017, p.1 - 5
Abstract
Restrictions on underwater sound levels are becoming more common as legislation is put in place to protect marine mammals. Conventional seismic sources meet the current regulations in the UK and the Netherlands. This is not the case with more stringent environmental restrictions, offshore Germany, which consider the total Sound Exposure Level at preset distances from the source. Therefore, modelling accurately sound propagation emitted by seismic sources in the water column is of paramount importance for planning 3D seismic acquisition and selecting an appropriate source that meet local requirements. The challenge is to balance the source energy required to properly image the subsurface with sound emission regulations. Data from Underwater Sound Measurements (USM) acquired during a seismic survey is required to validate existing modeling methods. A program was setup in 2014 to acquire USM data during a 3D seismic survey shot in the Dutch offshore in shallow water. Alternative airgun source setups were tested over a selected line of the survey. The USM data of the various source configurations were compared to results of two modelling methods. This paper describes the details of the USM acquisition, compares results of the USM data with existing models, resulting in discussion and conclusions.