M/V Bernier-A Unique Canadian Seismic Vessel
Authors: Parker K. , Clark P. 
Published: March 2010

Petro-Canada's new seismic vessel, the "M/V Bernier" is a world-class geophysical data acquisition vessel designed and built in Canada. Since its commissioning in July 1983, the vessel has operated in the Scotian Shelf and Grand Banks areas, offshore Barbados, and is presently shooting 3-D seismic in the Gulf of Thailand.

The expense of offshore exploration programs demands that the highest quality seismic data be available to geologists and geophysicists. For this reason, great emphasis was placed on designing a vessel which was optimized for seismic data acquisition using state-of-the-art equipment and technology. In order to meet the needs of both Petro-Canada's offshore frontier exploration programs and those of Petro-Canada International Assistance Corporation (PCIAC) world-wide, special features were incorporated into the vessel design to enable extended operations to be carried out both in arctic and tropical waters.

To ensure high-quality data collection a hull form was developed, which was hydrodynamically quiet and acoustic transmission was minimized by extensive vibration isolation of machinery.

Petro-Canada required a high degree of safety and survivability. For this reason, the vessel was designed to the same stringent stability standards as passenger vessels and is ice-strengthened to fulfill the requirements of the Canadian Arctic pollution prevention regulations for a ‘Type B’ vessel.

A maximum crew complement of 41 persons including company representatives, scientists, seismic and marine operating personnel can be accommodated.

The design was carried out by Evan's, Yeatman and Endal (Associates) Limited, of Dartmouth, Nova Scotia who worked closely with Petro-Canada staff. Detailed design commenced in June 1981. By October, the design was complete and construction bids were being sought from Canadian shipyards.

Hull Design

The performance criteria set by geophysicists required the ability to tow a 5 km long streamer cable and a 61,800 cm3 (3772 in.3) air gun array, at 6 knots, firing the air guns at 10-second intervals. This requires approximately 80 m3/min. (2800 ft3/min.) of compressed air at 14 MPa (2000 psi).

Extensive optimization of the hull was carried out by computer analysis and model tests at the Netherlands Ship Model Basin (N.S.M.B.). Conventional resistance, propulsion, seakeeping and maneuvering tests were conducted in towing tanks using a 1:25 scale model. A 1:10 scale model was used in a depressurized towing tank to study wake distribution and propeller cavitation inception.

Main Machinery and Propulsion

Considerable detailed study of suitable propulsion and power management systems was undertaken. Seismic vessels have widely varying power requirements due to the high compressor load at slow ship speed while shooting, and a requirement for rapid transit, in this case 12 – 14 knots, between survey areas.

The final choice, based on flexibility, reliability and efficiency was a fully integrated A.C./D.C. diesel electric propulsion system.

It is commonly considered that diesel electric vessels area complex and expensive, however, using proven off-the-shelf equipment originally developed for the drilling and mining industries, the cost penalty for a modern diesel electric system is small and easily amortized.