Guidelines for the use of multibeam echosounders for offshore surveys

Version history

May 2024 Rev. 2.1 – Bookmarking of figures, tables and equations; no change to content

July 2015 Rev. 2 – Extensively revised and updated during 2014 to bring document up to date with changes to technology and practice

January 2006 Rev. 1 – Guidelines reviewed and endorsed by UKOOA’s Survey & Positioning Committee

November 2001 – Initial publication

Overview

The growth in the use of multibeam echosounders (MBES) in the past two decades has been in part due to the ability of these instruments to cover wide swathes of the seafloor in a single pass. In addition, increases in processing power and availability of data storage at reasonable prices have made the technology accessible to a wider range of users.
With high-resolution bathymetry obtainable over wide areas and with acoustic frequencies ranging from 10 kHz to over 500 kHz, MBES offer the potential for great accuracy and provide detailed seafloor imagery with scales of economy unavailable from traditional single-beam echosounders.

In commercial surveying, MBES are employed for a variety of applications and are installed in ships, survey launches and in towed bodies (fish), on remotely operated vehicles (ROVs), in autonomous underwater vehicles (AUVs) and untethered underwater vehicles (UUVs).

Although MBESs have been in use since the 1960s, their track record in commercial marine operations can be traced back to the early 1990s. When this document was first proposed, no specifications or guidelines existed in the public domain that specifically addressed the use of MBESs for offshore surveying. To remedy this situation, IMCA’s Offshore Survey Division established a working group to oversee the preparation of these guidelines as a means of augmenting existing documentation and to provide a guide for future specifications.

The revision of the guidelines in 2013 and 2014 saw a thorough general and technical update to wording, updated references, and reflection within the document of changes to technology and practice over the ensuing years.

Contents

• Preface
• Glossary of Terminology
• Introduction
• Multibeam Echosounders
• Subsea Vehicles and Systems
• Sensor Installation, Calibration and Location
• Calibration Tests (Patch Tests)
• MBES Data Processing
• Standards for MBES Surveys
• Survey Planning
• Bibliography