END OF SEASON FIELD REPORTS

2007-08 End of Season Field Reports


National Ice Core Laboratory (NICL) Activities at WAIS Divide 2007-2008 (I-478)
NSF-OPP supported
PI: R. Randall Schumann (U.S. Geological Survey)

Field Team:
Geoff Hargreaves
Brian Bencivengo

Season Objectives:
1) Unpack, assemble, calibrate and test core-handling equipment in processing arch
2) Provide hands-on training to core handlers for all CPL operations and procedures before drilling commences
3) Upon startup of drilling operations confirm all procedures and modify as required. Provide additional hands-on, step-by-step training for all handlers
4) Troubleshoot and modify and/or repair CPL system components as required
5) Review core logging data each day for accuracy and completeness
6) Provide oversight for CPL operations during regular shift
7) Provide daily update to WSD-SCO representative on progress, issues arising, and ice retro requirements
8) Ensure that all CPL systems are prepared for winter-over storage in the processing arch
9) Pack all retro cargo
10) Upon leaving camp, ensure that all cargo is entered correctly into the retro cargo stream, meeting with the RPSC cargo coordinator at MCM. Re-pack as necessary and acquire all northbound TCNs before re-deploying.

Field Season Overview:
Equipment was unpacked, setup, installed and tested.

All individuals were trained on all aspects of the core handling operation, starting with core reception / logging station, 1m measurement logging and cutting station, database operation, cart loading, core packing, loading core boxes onto wood skids, gantry / hoist operation and loading skids onto air force pallets.

The core handling operation for WAIS divide uses several pieces of equipment that have never been utilized before in a field core logging operation: computers (in warm boxes) accessing a database, digital measuring sticks, and a Fluid Evacuation Device (the FED, for removing most of the drill fluid off of the core). We are also moved ice core 16m at a time on roller racks, instead of moving individual cores.

Most of the components worked flawlessly.

The Fluid Evacuation Device removed more of the drill fluid from the ice core in Antarctica than it did during testing in Greenland.

The wine netting did an excellent job of containing the core.

The wine net applicator was not robust enough and would allow the netting to tear away from the holder while core was being pushed into the netting; we changed to clamping the netting onto the FED. Unfortunately the force required to push the core into the net began to break the core. Wine netting application will be redesigned.

The BALLUFF digital measuring sticks worked flawlessly, including the line laser pointers.

The buffer table (used to move core from the receiving table to the 1m logging/cutting table, also used to store full runs of core should the drillers get ahead of the logging operation) had no problems.

The 14-inch circular saw proved to be a superior choice for cutting ice. Although the 14-inch circular saw does have difficulties with brittle ice, they are considerably less so than with band saws.

The computers and laser printers in their warm boxes worked continuously once they were put online.

The core logging database (DB) failed during operation. The DB added an extra page for 1m tray logging, this threw off several tracking counters causing the system not to allow any more data entry. While this was a major disappointment, it was not a major problem. We simply reverted to logging into paper notebooks.

The core lifters (hand crank platform hoists) worked well.

Roller racks: moving core on roller racks worked well. We observed that it does take two people to move a rack safely.

The drying booths dried the carts of core in 12 hours or less.

The hoist /gantry worked smoothly. We had some difficulties with the hoist traversing on the gantry due to frost buildup on the I-beam from the refrigeration unit defrost cycles.

The pallet jack was indispensable, but had some problems due to the snow on the floor, also mostly from refrigeration unit defrost cycles.

The Pallet loader for lifting the wood skids onto the air force pallets worked well. It has a couple degrees of tip when lifting the skids of ice, which did not constitute a serious problem but required operator attentiveness.

The Air Force Pallet roller setup worked extremely well.

The refrigeration units kept the working area below 15°C, but were noisy and the defrost cycle left lots of snow on the floor, which made the floor slippery.

During the setup and subsequent operation, there were some minor changes to equipment configuration that had to be made, which were easily accomplished in the field. A couple of examples: The 4m tray return rack had to be repositioned closer to the receiving table, and blocked up ~8 inches to allow clearance with the receiving tray tower section. A support leg was added to the 2m cutting tray at the cutting station.

Three items were returned to CONUS for reconfiguration:
1) The FED needs to have sturdier mounts.
2) The 4m receiving table needs mounts that are adjustable for height and level.
3) The wine net applicator must be rethought, redesigned and fabricated.

All computers and equipment that requires updates and repairs were returned to NICL.

The FED and tower sections for the receiving table were returned for equipment mounting rework.

All other sensitive equipment was shipped to McMurdo for warm storage.

Equipment left on site was covered and bagged to keep out frost and snow.