David Honig is a graduate student in marine science at Duke University in the lab of Dr. Cindy Van Dover. He is participating in LARISSA, a 2 month multinational expedition to study the causes and consequences of the ice shelf collapse. He will be posting regular updates on the expedition exclusively for Deep Sea News readers!
24 January 2010
Plans to sample benthic invertebrates via megacore ran into a snag today. For the megacore to work properly, it needs some indication that it has hit seafloor. Barilari Bay doesn’t have a seafloor so much as a “sea cushion” consisting of tens of meters of ultra-soft rock flour that swallow the megacore in muck. Our marine techs think the megacore needs “snow shoes” to get purchase on the sediment surface.
Luckily, plans to sample sediment via jumbo Kasten core have been spectacularly successful. We recovered a full nine meters of sediment from a trough near the head of the fjord that should keep our quaternary and geosciences team occupied for the next day or so. In addition to providing a record of climate and ice-shelf coverage for the bay, the core will allow us to answer questions of great interest to biologists: How high is the sedimentation rate? How much organic carbon does the sediment contain? How “busy” is the sediment, biologically speaking? Compare Kasten cores between Barilari and Andvord Bay will help develop a picture of how glaciers structure life in these two fjords.