November 23: Gravity, analysis

Gravity core sampler


November 23, 2006
On board the RV Yuzhmorgeologiya
In transit of the Drake Passage towards Antarctica

The Korean researchers were up early today, using a gravity core to capture a deep-sea sediment sample. At this location, the sea floor is over 3500 meters (>11,000 feet) beneath the ocean surface. But the heavy weight of the gravity core drove a section of pipe more than 8 meters (25 feet) into the soft sediment. Korean scientists will be examining this core for evidence of past climatic change.

Drs. Stafford and Matsumoto have been busy extracting and interpreting the data gathered by the Drake Passage hydrophone. Kate was pleased to see the sound signature of a blue whale that must have been in this area shortly before we recovered the hydrophone. The Antarctic blue whale population was hunted to depletion by the 1930’s and only protected internationally in the 1960’s.
This hydrophone records sound between .1 and 110 Hertz at 250 samples/second, a sampling range ideal for recording the low frequency sounds generated by the great whales, as well as underwater seismic events and ice movement.

The cuisine on our Russian vessel is always superb. Tonight’s meal was roast duck, but it wasn’t until much later that I remembered that today was Thanksgiving. Perhaps the cook hadn’t realized the significance, but I appreciated the culinary coincidence.

The Yuzhmorgeologiya is steaming at 10 knots for King George Island, just off the coast of the Antarctic Peninsula. We expect to arrive during the early morning hours, anchor, and to begin off-loading materials and personnel after breakfast.

Tomorrow: A return visit to the Gentoo penguin colony!