By Richard Chiverrell
The Britice-Chrono Cruise through the Celtic, Irish and Malin Seas, and onwards around Ireland takes, in order, the Transects T4 (Irish Sea West), T3 (Irish Sea East), T7 (Malin Sea – Barra fan), T6 (Donegal) and T5 (Galway – Porcupine Bank). Leg 1 ran from Friday 18th July to Monday 4th August culminating with three cores as part of the Malin Sea transect, before our efforts in Donegal Bay were curtailed by rising seas and inclement weather. The port stop in Killibegs in northwest Ireland was a welcome break and chance to recharge batteries. It was also change time in terms of the Science Crew, with James Scourse, Sara Benetti, Fabio Sacchetti and Dan Praeg taking leave of the ship. Joining in Killybegs were Stephen Livingstone and Kevin Schiele, and Jenny Gales switched from BGS crew to the Science team for the second leg. Alex Ingle joined our throng as Film-maker. It was all change for the BGS core team, as we bade farewell to Davie, Alan, Keith, Mike and Joe, and welcomed (Day team) Iain (Rab) Pheasant, Apostolos Tsilligianis and Claire (taciturn) Mellett (Night team) David Wallis, Garry McGowan and Connor Richardson. Somehow I failed to leave the ship in Killybegs, either a desire to runaway to sea or perhaps oversleeping.
T6 Donegal Bay: the weather and seas relented for our time in and departure from Killybegs. we sailed in not the glorious sunshine that greeted our arrival and days sampling the shops and tea-rooms of this pretty fishing /industrial port in northwest Ireland. Our departure route was a sprint west, before a crisscross survey along a pronounced inner moraine from which seven cores were identified and sampled along and either side of this moraine complex. A further 13 were picked and recovered from an ~80 mile breakneck transect to the shelf break moraines fronting Donegal Bay. All in we were pretty pleased, another transect in the bag, a total of 20 vibrocores, just leaving the high risk more exposed locations: Malin Sea and Galway Bay – Porcupine Bank. Highlights included excellent thick sequences of laminated glacimarine muds, with occasional drop-stones and shells, some high priority targets for radiocarbon dating across the sea floor moraines preserved in Donegal Bay. In particular the blitzkrieg coring marathon 20 vibrocores in 27 hours to gently ease the 2nd leg BGS core team into the Britice-Chrono / RRS James Cook way of life, they loved every minute of it…..
T7 Malin Sea – Barra Fan: it is amazing what can happen while you sleep; go to bed mid afternoon on the 6th Aug, when you wake midnight 7th Aug it is the start of the survey 100 miles further north in the Malin Sea (T6 sampling complete). The dynamism of a 24 hour work programme and day/night teamwork keeps you on your toes. The morning meetings chaired by the Captain (John Leask) focused on all manner of boat matters from plumbing to safety and our dynamic science plan. Featuring heavily as we approached the Malin Sea survey was the approaching remnants of Tropical Storm Bertha, though not actually to affect us that much, it reminded us how fickle weather and sea state can be, and how subject to conditions our programme could be before we would go alongside in Southampton on the 25th August. All in the Malin Sea T7 research saw us complete 40 cores, including 3 piston cores, and what felt like thousands of miles of geophysical survey. The transect saw heroic maintenance actions by the BGS team, repairing the electronics that drive the hammer system and a retraction winch cable (replaced in the 30 mins between core stations). By the end of T7 our tally of cores stood at 154, with >75 hours of hammering on the sea floor, devouring core catchers and our stocks of core tubes, and putting a heavy workload on our trusty vibrocorer. Hammering through diamict stiffened beneath the pressure of ice 24-26,000 years ago and smashing into the occasional lump of rafted bedrock, all contribute to a less than easy life. Highlights included thick sequences with glacimarine muds and possible diamicts at or near the continental shelf break, thick (>7m) piston core profiles from the deeper ocean and continental shelf slopes (>1500m of water) and further excellent cores in the outer sector of the Sea of the Hebrides, selected as we had to shelter from some choppy waters. A very satisfied team could take leave of the Malin Sea for pastures new……
Selected photographs by Alex Ingle