||May 27, 2000, pm
Memorial Day Weekend
5:30 pm 63 42 S, 57 13 W 21 F, 30 knot winds.
Coming down to the wire with our work here in Antarctica. Per Captain Joe, all science ends at 2 pm tomorrow.
Currently we are sitting in the northern end of the Prince Gustav Channel, preparing to do a jumbo piston core. The jumbo piston core has the potential to recover over 90 feet of sediment. Sediments in this area are very thick, probably resulting from the currents in the channel slowing as the channel widens causing the sediment to come out of suspension and rapidly accumulate in the area. Long cores recovered in areas of rapid sedimentation allow for a very detailed analysis of the climatic record. The site for this and one jumbo core tomorrow were chosen using seismic profiles of the bottom. Bottom profiling with the side scan sonar also shows grooves in the sediment
caused by drifting icebergs which occurred in a time when the sea level was lower than it is today.
Jumbo piston coring is a very involved operation. Most of last night and this afternoon was spent by the MT's setting up jumbo coring equipment. While they were working on deck we were processing 3 kasten cores taken to confirm that the sites chosen from the seismics were good ones. Two jumbo cores will be taken, one tonight and one tomorrow morning. Total time for one of these cores including lining the core pipe, deploying & recovering the corer and removing the cores is around 5 hours.
Photos of operation will follow in the next e-mail.