OMG Nuliajuk Lake Melville 2013

photo credit: James Muggah

Nuliajuk 2013 Lake Melville Mapping Operations - Preliminary Results

James Muggah¹, Christine Legere² and Weston Renoud¹
¹Ocean Mapping Group
Dept. Geodesy and Geomatics Engineering,
University of New Brunswick
²Department of Geography,
Memorial University of Newfoundland

Nuliajuk 2013 Index

The web page presents an initial overview of the 2013 multibeam mapping program of the MV Nuliajuk. The Nuliajuk is a vessel owned and operated by the Government of Nunavut (GN), Dept. of the Environment, Fisheries and Sealing Division. This is the third year of Nuliajuk operations (second involving the Ocean Mapping Group), through a partnership between GN, ArcticNet (including the University of New Brunswick (UNB) and Memorial University (MUN)) and the Canadian Hydrographic Service (CHS). The vessel was equipped with a geoscience/hydrographic survey suite including multibeam and subbottom.

The instrumentation, owned and operated by the Ocean Mapping Group at UNB, includes:

Kongsberg EM3002 300 kHz multibeam sonar.
Coda Octopus F185 GPS-aided inertial system.
Knudsen 3200 Chirped 2 element 3.5 kHz subbottom profiler.
C-Nav 3050 - RTG GPS receiver.
C-Nav 2000 - RTG GPS receiver.

The survey system complements the existing sonars suite on board including :

RDI 300 kHz WorkHorse Mariner ADCP
Furuno CH-300 searchlight sonar (60/153 or 85/215 kHz)
Furuno FCV-30 (38 kHz) fisheries multiple-beam sonar.

The instrumentation, loaned to the Ocean Mapping Group from the CHS, includes:

AML SVPlus CTD.
Coda Octopus F185+ GPS-aided inertial system (spare).

Details about the installation of survey equipment can be found here.
To view all multibeam bathymetry and backscatter the Ocean Mapping Group has collected up to 2012, click here.

Nuliajuk Track Overview

Lake Melville Track

Lake Melville Coverage

For 20 days in June/July, the Nuliajuk operated in Lake Melville and the Goose Bay / Terrington Narrows.
The Lake Melville survey saw a significant portion of the central area of the lake mapped. The weather co-operated for almost the entire duration of the mapping, leading to high quality bathymetry and backscatter. On average, five lines (~20 Nm in length) were run per day allowing two corridors to be built into anchorages at Mulligan Bay (Northwest) and Etagaulet Bay (Southeast).
There were minor problems in Lake Melville with the F185 motion sensor, the initial calibration took more than the required time to complete. This is probably due to the baseline offset between the antennas. It was also noted that high speed maneuvers speed up the calibration. Near the end of the survey (~JD178), the F185 heading sensor began to drift, requiring a few figure eights to get it to lock on.
For the Narrows surveys a Trimble 5700 GPS base station was set up in Northwest River. The distance from the base station to Goose Bay narrows was ~15km and to the Terrington Narrows was ~25km. The base station will be used in post-processing to increase the horizontal and vertical accuracy allowing the surveys to be referenced to the ellipsoid, effectively removing the effects of the tide.

Melville Overview

Lake Melville	Terrington Narrows	Goose Bay Narrows

page created by JMuggah, October/November 2013