Sunday, 17 May 2009

CV09_02 Survey of Dingle, Tralee, St. Finan's and Ballinskelligs Bays

The second INFOMAR survey of 2009 has just been completed in Dingle, Tralee, St. Finan's and Ballinskelligs Bay in Co. Kerry using the Marine Institutes research vessel Celtic Voyager. The month long survey was divided into fortnight long legs and kicked off from Galway Docks on Friday May 15th, just days before the arrival of the Volvo Ocean Race stopover. From May 16th to 29th, the survey was focused in an area east of a line from Slea Head on the Dingle peninsula to Doulus head on the Iveragh peninsula into the 10 metre depth contour just offshore of Inch and Rossbehy strands. The second leg from May 29th to June 12th was surveyed the remaining area of seabed in outer Dingle bay, around the Blasket Islands and further south to St. Finan's and Ballinskelligs Bay.

With the proposed area to be surveyed around Dingle bay complete before the end of the survey, the Celtic Voyager relocated to Tralee bay to survey the remaining area of seabed between the coverage from a LiDAR survey of the inner bay in 2008 and the survey of Shannon estuary and approaches earlier in the year.

Images generated from MBES data showing the wreck of the Manchester Merchant which lies 11 metres below the surface in Dingle Bay. The 137 metre long merchant vessel sank in January 1903 after being towed into Dingle Bay following a fire on board. The cargo of the ship included bales of cotton from New Orleans in transit to Manchester. Bourke, Edward J. "Shipwrecks of the Irish coast"

View of sea cliffs on Dingle Peninsula from Celtic Voyager.

View of Dingle lighthouse from Celtic Voyager while entering Dingle Harbour for crew change on May 29th.

Sunset in Dingle Bay on May 25th.

All INFOMAR data is available for free download here.

Friday, 8 May 2009

CV09_23 Ground Truthing in Bantry and Dunmanus Bays

From 22nd to 28th April, INFOMAR staff were amongst a crew of scientists that were busy collecting a large number of ground truthing samples from the seabed in Bantry and Dunmanus Bays in Cork on the Celtic Voyager as part of research by Dublin City University (DCU) on pockmark features in the bays. Also included were scientists from University of Limerick (UL) and Aquafact Environmental Survey Specialists. Before the transit to west Cork, mobilisation, testing and training was done in Cork Harbour.

Day Grab recovery from Cork Harbour of coarse grained sediment and large shells.

The 290 metre long Grand Princess cruise liner in Cobh.

Gravity cores, box cores and day grabs were recovered from the seabed with video footage from selected sites. In all over 5 days of 24 hour operations, 132 sampling stations and 12 gravity core stations were covered. The physical, chemical and biological content of these samples
will be analysed to gain an insight into the nature of the seabed in the bays and also close to the pockmarks features. The leg ended in demobilisation in Castletown Bere and was deemed very successful for all parties.

Plan view of day grab recovery. Note the muddy nature of the seabed and the brittle starfish recovered in the grab.

Elevation view of box core recovery. Note the change in colour of the sediment from green/brown to grey around 5 cm from the surface. Sediments recovered were generally composed of mud and clay.

Recovery of the gravity corer with 2 metre barrel from the A-frame of the Celtic Voyager. Average recovery from the corer was around 1.20 metres of mud and clay.

View of the west Cork coastline on the Sheep's Head peninsula from inner Dunmanus Bay.

All INFOMAR data is available for free download here.