Reference Surfaces

Reference Surfaces produced by the MAC can be downloaded from the Marine Geoscience Data System. If you have a Reference Surface to contribute please contact us at

E/V Nautilus Spring 2014 Quality Assessment Report

Multibeam System: 

Summary and Recommendations

  • As it stands now, the EM302 and associated sensors are working well as compared to other EM302s evaluated recently. The patch test revealed very slight residual angular offsets, indicating a successful reinstallation of the MRU and no apparent change to any other component of the system.

E/V Nautilus Spring 2015 Quality Assessment Report

Multibeam System: 

Summary and Recommendations

  • Heading into the 2015 operating season, the EM302 and associated sensors aboard E/V Nautilus are working well compared to previous evaluations and to other EM302 systems examined recently. The patch test showed no pitch or yaw bias and only a very slight residual angular offset for roll, indicating no major changes to the system geometry.

Reference Surfaces

The following cruises include Reference Surface Surveys: (Atlantic) (Pacific) (Pacific) (Pacific)

Falkor Fall 2014 Quality Assessment Report

The EM302 and EM710 multibeams were successfully calibrated and verified for use with both the loaner Seapath MRU and the new POS MV. Angular offsets were small except for the roll bias for both the EM710 and EM302. As both multibeam systems have the same large roll bias, it is likely the result of a shift in the mounting angle of the MRU. Both SIS acquisition systems have been updated with the new calibration results.

Falkor Spring 2014 Quality Assessment Report

The transducer impedances are similar to baseline measurements in 2012 and with those taken in 2013. Transducer conditions, based on these tests, are acceptable and there is no sign of degradation of the transducer arrays.

Noise levels for the EM710 remain unchanged and very low. Noise levels for the EM302 have increased at higher speeds though they remain low when the ship is stationary in the water, suggesting that the increase is associated with flow noise and/or the propulsion system.

Introduction to Patch Tests

Basic overview of how and why to conduct a patch test.

2014 QAT Review of R2R MBQA Tests


The Rolling Deck to Repository (R2R) Program has developed programmatic quality assessment (QA) routines intended to identify suspicious data that may indicate sensor and/or operational problems. In order to assess the results of these QA tests and seek fleet-wide patterns in system performance and operation, this page provides an initial summary the results of R2R Multibeam QA tests for all sonar systems.

Tool: Sound Velocity Profile (SVP) Editor [v.1.0.5] [Deprecated]

This tool is no longer supported by the MAC, please use the SSP Library & Manager

For new installations:
1) Visit, login as 'anonymous' and use your email as the password.
2) Navigate to "fromccom/MAC_DATA/" and download,, and
3) "Unzip" each of the downloaded files.
4.) Follow the installation directions found in the "SVP Editor Manual v1.0.5.pdf" file located in the "Tools/SVP Editor" directory.

NOAA Ship Rainier 2013 Multibeam System Review

Sensor geometry reconfiguration was successfully completed and tested on Rainier and a 14 ms orientation time delay was applied in SIS to accommodate an observed latency in the transmission of motion data from the POSMV to SIS. We feel that these two modifications will improve the data quality with the geometry reconfiguration allowing for successful application of TrueHeave in postcprocessing and the time-delay configuration improving the data quality of soundings as corrected in real-time by SIS.

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