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Sorry for the break in communications. We have had a very busy past couple of days and I've been unable to get away long enough to get out a message.
In Andvord Bay we collected a 90 foot jumbo piston core. The jumbo piston corer is lined with 4 inch diameter 10 foot long sections of thick wall PVC pipe. When the corer comes back on deck, a hydraulic ram pushes these sections out of the steel casing pipe. We cap the end of each seciton as it comes out and then 2-3 people are needed to carry the liners filled with mud into the lab. This is not a job that can be done in rough water. The importance of these long cores is that they provide a record back much further in time than the standard 10 foot core. Obviously if you are going to drop a 90 foot pipe with 1700 lbs of weight on top over the edge you need to have a sense that the bottom is soft. We commonly check the site with a Kasten core first to evaluate the bottom and then go for the big corer. Luck plays a big part.
Last night I went to bed around 1:30 am planning on being woken up around 4 am to assist with another jumbo piston core. When the alarm went off at 6 am I knew something did not go well in the night. One look on deck confirmed it. The jumbo piston core casing, 4 inch inside diameter steel pipe, lay on the deck bent in a none to gentle curve. The bottom had seemed soft at the site and we figure that the corer hit a large rock or outcrop. We plan one more attempt later tonight as a final fling of data collection before we head north for South America and eventually the US.
Currently we are doing additional mapping of the sea floor and transiting to a site to do another Kasten core and a jumbo piston core.
With all the snow and ice covered land around and the gentle water in these channels I'm constantly forgetting we are on the ocean. Last night I worked with Dr. Pat Reynolds of Hamilton College emptying a drege dragged over the channel bottom for a half hour before being brought back on board.
The dredge was loaded with rocks which I expected, but then there were the sponges, sea squirts, shells, brittle stars, and other life from the bottom of the sea. With all the attention we have been paying to the subsea muds, and the topography of the sea floor I had lost perspective of what the interface between the water and the sea floor would look like. I guess I'd pictured a barren plain with little life. The opposite is true. The sea floor in the Antarctic is very diverse with animals living on the sea floor and in the top few inches of mud just below the water/mud interface.
We spent this morning at the Chilean research station at Waterboat Point (64 49 S 62 51 W). The base is currently unoccupied, and it has become home to penguins. We crossed to the island by Zodiac raft and were greeted by hundreds of penguins. They move away from you if you approach to closely, but seem relatively unafraid. I think they know they have a better chance with us than with the lepord seal we saw swimming just offshore.
Antarctica is protected by the Antarctic treaty which includes treatment of the land, water and wildlife. Picking up a penguin is a very tempting thought, but the warning of a $10,000 fine for such an action, given just before we left the ship, quickly puts the temptation to rest.
Lots for film was used this morning. The penguins are moulting off their downy feathers and getting ready to head north for the winter. The air was full of fluffy feathers and the penguins would pluck at themselves for a while then go in for a quick swim to wash off the loose feathers and catch a bite to eat. When they came out, the water would bead up on their newly exposed feathers and run off. They find a nice sunny space and stand with their back to the sun, absorbing the energy on their dark backs. Cats seem to have a similar affinity for sunny spots.
Hope all is well with you. We officially finish work at 2 am tonight (tomorrow morning), according to the Captain, so the final push is on to collect as much data as possible before we start the trip back across the Drake Passage to Punta Arenas.
Best wishes to all,
Dave Tewskbury
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