OMG Nuliajuk SE Baffin Leg 1 2013

photo credit: James Muggah

Nuliajuk 2013 SE Baffin Leg 1 Mapping Operations - Preliminary Results

John Hughes Clarke and James Muggah
Ocean Mapping Group
Dept. Geodesy and Geomatics Engineering
University of New Brunswick

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.

Overview map from Qikiqtarjuaq to Pangnirtung.

Apart from a 2 week window in mid July, all the Nuliajuk mapping in Nunavut took place during a 29 day period covering the month of October. This report will covert he first 17 days of that cruise. The UNB mapping team boarded in Qikiqtarjuaq (Oct. 2nd) and disembarked in Pangnirtung (Oct. 19). The main target areas were:

Qikiqtarjuaq vicinity
Kangert Fjord
Southwind Fjord
Akpait Fjord
Clephane Fjord
Ignit Fjord
Touak Fjord
Aktijartukan Fjord
Kekerten Island Region
Pangnirtung Fjord

Overview map of the Nuliajuk track, colour
coded by day, from Oct. 2^nd to Oct. 19^th.
Survey areas are outlined.

Qikiqtarjuaq Vicinity - ArcticNet site

ArcticNet Sealevel History: one day around Broughton Harbour and Broughton Island. The survey was specifically designed to expand the coverage of the 2012 surveys to gain coverage over specific dive sites by Siferd and the 2013 field work done by Memorial University.

Kangert Fjord - ArcticNet site

Three sites were investigated for terraces indicating sea level history, two on the way into Kangert and one at the head of the fjord. All three sites contained useful submerged terraces.
The head of Kangert fjord and Recce B sites were both investigated using an underwater camera. The camera will help with ground truthing the multibeam backscatter in identifying submerged sediments.
The head of Kangert and Recce B sites would both be suitable anchorages.




Approximate drift (from bottom left, to top right) while underwater camera was in use.

Approximate drift (from bottom, to top), in both sections, while underwater camera was in use.

Southwind Fjord - ArcticNet site

Southwind Fjord was investigated for a suspected terrace at the head of the fjord. A few areas near the outer edge of the fjord were too deep for the EM3002 to track (>300m). The Nuliajuk therefore deliberately steamed into shallower water to obtain useful sounding data.
The head of the fjord proved to have an active delta, with a nice channel system cutting through the softer sediments. It would be useful to re-survey this channel in following years to determine the activity of the delta front. See Squamish Prodelta Experiment for other examples of active delta systems.
On the way out of the fjord, at a lower tide, two rock outcrops were found which had not been indicated on the chart or the Natural Resources Canada toporama products. A safe passage around the East side of the rock outcrops was mapped.
The Knudsen Chirp 3200 echosounder had an AC to DC power board failure during the survey. In the remoteness of the area, a new power board was not readily available. The board had to be ordered, shipped to UNB and carried up to the Nuliajuk in the hands of Weston Renoud, who boarded the ship in Pangnirtung.

Akpait Fjord - ArcticNet site

Akpait Fjord was chosen for a potential terrace at the head of the fjord. Upon entering and investigation the head of Akpait Fjord, it was found to have a small active channel system. Weather and time permitted on the following day to map the sill at the fjord mouth. The sill showed evidence of a drowned channel system and an enclosed basin. A camera was used to ground truth the area. A line was run from an area of low backscatter, upslope, across an area of high backscatter and back to low backscatter. The area of high backscatter was shown to contain numerous rocks of various sizes; while the area of low backscatter was shown to be a sandy bottom with traces of shells.




Approximate drift (from bottom left, to top right) while underwater camera was in use.

Clephane Fjord - ArcticNet site

Clephane Fjord was chosen for several potential terrace sites. The two Recces on the way into the fjord and the head of the fjord did not show any significant signs of terraces.
A nice channel and potential Esker can be seen at the head of the fjord. There was also a strange rock outcrop in a fan or finger-like pattern, near the head of the fjord.

A storm with ~40 knot sustained winds with gusts registering 70+ knots kept the Nuliajuk in Clephane Fjord for the night and the next day. A decision was made to create a new anchorage in "Pause Bay" while waiting for the seas to calm. Pause Bay revealed a smooth, flat, soft sediment bottom making for an ideal anchorage in a protected bay with depths consistently around 25-30m.

Ignit Fjord - ArcticNet site

Ignit Fjord was chosen for three potential submerged terraces.
The first, Inglis Bay, proved to be a safe anchorage, but did not show significant signs of a terrace at the correct depth. The transit out of Inglis Bay indicated a potential channel and sill requiring further investigation. Upon the completion of mapping, the sill and channel were clearly defined.
Recce A did not show significant sings of a terrace, although a safe anchorage with a nice deep hole was found.
The head of Ingnit Fjord showed significant signs of infilling and time was not allotted for further investigation. The safe route up to the head of the fjord will improve future access for tourism, fisheries and search and rescue.
A previously charted anchorage, Sakiak Anchorage, had a single sounding of 15 fathoms (~27.5m) on chart #7051 from an unknown track. Sakiak Anchorage was mapped and found to be a suitable anchorage.

Touak Fjord - ArcticNet site

Touak Fjord was chosen for three potential submerged terrace locations. In all, six possible terrace locations were investigated and one startling shoal.
The first two sites: "East of Falls Bay" and "Falls Bay" did not show any significant evidence of submerged terraces.
Touak Fjord Recce A showed evidence of an active channel system extending from the river on the West side of the fjord down to ~100m in the centre of the fjord.
The head of Touak Fjord indicated lots of infilling on the East side and a large channel on the West side next to the cliffs. The origin of this Western channel was not investigated further as the water depth was too shoal (<20m) for the Nuliajuk. A RHIB based survey launch could provide more detail in the shallow water in future years.
Both possible submerged terrace locations in Nallussiaq Fjord did not indicate any significant signs of terraces.
The rock shoal at the mouth of Touak Fjord should be noted for any vessel traveling in the vicinity. The minimum depth of this rock outcrop was not found, the shoalest point found being 7m at mean sea level. A safe zone around the shoal was mapped, however more investigation is needed by a small launch to find the minimum depth.


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Aktijartukan Fjord - GN/DFO

The NGMP Arctic Char monitoring program in Pangnirtung is a parternship between DFO Science and Pangnirtung HTO.
DFO provided three target fjords, requesting water sampling, environmental and bathymetric data to be collected in 2013 or 2014. Aktijartukan fjord was a GN/DFO target area for fisheries research.
The Nuliajuk spent a day and a half in Aktijartukan Fjord, collecting high resolution multibeam bathymetry, single beam bathymetry and CTD samples. The decision was made to survey Aktijartukan fjord completely (depths >20m), rather than a Recce survey in each of the three requested fjords.
The single beam survey was performed using a Lowrance single beam echosounder equipped to the Nuliajuk RHIB. This clearly demonstrates the effectiveness of a launch based survey system to investigate shallow (<20m) water depths and finding the least depth on shoals. Equipping the RHIB with a semi-permanent shallow water multibeam would further increase the coverage and shallow water capabilities of a launch based system.



	The map on the left shows the single beam coverage of the Nuliajuk RHIB in Aktijartukan Fjord. The RHIB was able to ring the shoreline, shoals and constrictions, while also zig-zagging to find the 20m contour. Any shoal that was too shallow for the Nuliajuk (<20m) was surveyed using a star pattern by the RHIB to find the least depth.

Aktijartukan Fjord CTD casts. Location on left Sound speed distribution on middle left Temperature on middle right Salinity on right

Kekerten Island Region - GN

The corridor to the East of the Kikistan Islands was expanded from the 2012 surveys. Two shoals were investigated, one 15m and the other 30m. Safe passage was mapped around each shoal and least depth was found.
A new corridor from the Northeast tip of Kikistan Islands, just to the South of Brown Harbour was mapped. This route was not previously charted and will begin to provide safe passage into Kingnait Fjord or to the Eastern side of the Kikistan Islands.
A ship wreck in Kekerten Harbour was found in 2012 and further investigated in 2013. Several passes with the EM3002 were done over the site with water column logging. Two underwater cameras were used to image the wreck, one from the surface and the other was submerged at a depth of roughly 6m. Both Cameras clearly show the man-made object sitting on a sandy bottom surrounded by kelp. A mast, or similar feature can be distinguished in the multibeam and surface camera images.

New Kikistan to Pangnirtung Corridor

Kikistan Island Corridor building and Shoal Investigation


Kekerten Harbour Wreck.	Water column along track slice from nadir to outer beams.

Image of wreck from surface camera	General outline of wreck from surface camera

Image of wreck from submerged camera	General outline of wreck from submerged camera

Pangnirtung Fjord - ArcticNet

The sill at the mouth of Pangnirtung Fjord was investigated to determine the deepest channel on the sill for sea level history. This deep channel would be the constricting depth of the fjord when sea level was lower. The deepest channel was found to be the Western most channel, just West of the 65^o 58' W longitude shoal at a depth of 29 metres.

page created by JMuggah, October/November 2013