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Victoria University Antarctic Research Expedition Science and Logistics Reports 1982-83: VUWAE 27

Field Work

Field Work.

The travelling conditions on the sea ice to Butter Pt. were very good with the first significant rough ice encountered east of Butter Pt. This leg of the journey took 11 hours by D4. On the Bowers Piedmont at Butter Pt. a cache of our seismic equipment, seismic explosives, 7 × 44 gal DFA and 2 × 44 gal Mogas was left for our return in mid-November. The east-west seismic line was located and bulldozed and three sea ice movement survey beacons established during the next three days. Pat Tinnely (K26 surveyor) joined K5 from Vanda during this period and was responsible for surveying.

The next leg from Butter Pt to Cape Roberts took a total of 16 hours and was broken into two days. Rough ice extending east of Butter Pt to Cape Bernacchi was avoided by travelling east along our seismic line then towards Marble Pt., along the American fuel train road. Travelling conditions from Marble Pt. to Cape Roberts were very good about three kilometres off the coast. Rough ice extended along the coast eastwards of our route coming in close to the coast at Cape Roberts but was easily negotiated.

Two days were spent camped at Cape Roberts while we began bulldozing a seismic road due east from Cape Roberts. An active ice crack was encountered 3km out which was impassable by D4 and caused the planned sea ice based seismic programme in this area to be abandoned. Ice thickness at the crack was measured page 36 and a monitoring survey begun. (Results of this survey are presented in Scientific Achievements). Macpherson and Paintin sat their final exam while at Cape Roberts. The tide gauge was established in about 20m of water before we left to camp at the Mackay Glacier tongue.

The sea ice conditions in Granite Harbour provided good travelling. Snow cover was minimal on the first year ice which penetrated to the front of the Mackay Glacier. Second year and multiyear ice was encountered westwards of the glacier snout. The second year ice was extremely hard with a scalloped surface except on the abundant frozen meltpools. This ice required a considerable reduction in travelling speed for comfortable riding.

The period 9-17 November was spent working in Granite Harbour with our base camp near the glacier tongue. The first part of our programme was to begin a movement survey of the tongue. Two sets of poles were put in on the tongue and surveying control was established on the Flatiron and on the ridge west of Cuff Cape. The New Glacier was used as a toboggan route to get people and surveying equipment to the Flatiron and Cuff Cape. Some difficulties were encountered on the bare ice at the snout of this glacier. Minor crevasses at the steeper top of the glacier were easily crossed. This part of the programme took longer than expected because new survey control was required and the initial difficulties of walking on the abundantly crevassed Mackay Glacier tongue. At the end of this part of the programme the surveyors (K26) left us by snotrac, checking the tide gauge at Cape Roberts for its continuing operation enroute to Butter Pt.

During the remainder of the time at Granite Harbour two good seafloor cores were taken within a large accessible sea ice filled crack in the tongue and at the front of the glacier. Current measurements were made and bathymetry measurements attempted. An electronic problem with the newly acquired echo sounder resulted in few successful measurements but this problem was fixed later in the season at the Blue Glacier. The weather was extremely good at Granite Harbour during this time and no days were lost due to adverse weather.

The seismic programme required us to leave for Butter Pt. on November 18 reluctantly bringing to an end the oceanographic work in Granite Harbour.

The journey from Cape Roberts to the Butter Pt. seismic line took 15.5 hours. Two days were spent awaiting the arrival of Ray Dibble and part of the seismic line was reflagged in poor weather during this time. K26 joined us to resurvey the sea ice beacons on November 27.

The seismic programme at Butter Pt. was completed on November 28 when we moved to the Dailey Islands, meeting the Geophysics Division party led by Tim Stern (K7) and continued a seismic programme in this area. The journey took 8 hours by D4 and of this about 1 hour was spent extracting an obstinate cantago sledge from a recently formed 1.5m wide ice crack trending east from Butter Pt. The sledge was extracted without much difficulty and was at no time in danger of losing its load. A further to wide crack trending eastwards from the Stranded Moraines was easily crossed.

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The seismic programme at the Dailey Islands was completed on December 3. K7 and Dibble/Paintin returned to Scott Base. The next day while the remainder of K5 moved to the front of the Blue Glacier. A good seafloor core was obtained about 200m off the glacier front. We were joined by the Scott Base mechanics/science technician for a night while they replaced the engine on one of the Snotric toboggans, and examined the echo sounder.

The period December 7-9 was spent making bathymetry measurements from the Blue Glacier to Cape Chocolate, Cape Chocolate to Dailey Islands. Bathymetry measurements were also made at the shot points along the Dailey Islands seismic lines and along the McMurdo Ice Shelf front. A coring attempt near the Dailey Islands was only partially successful because of the compact sandy bottom.

K5 returned with the D4 to Scott Base on December 10.

Repairs were made to the toboggans enabling Macpherson and McLeod to set out for Explorers Cove in New Harbour 2 days later. At Explorers Cove they met the K26 surveyors and then moved to Butter Pt. to complete the final surveying of the sea ice movement beacons for this season. 3 days were lost owing to adverse weather. The Dailey Islands seismic lines were also surveyed before returning to Scott Base.

The "clean up operation" and return of equipment took just over a week. The sampling equipment required for the "Glacier operation" was prepared in readiness for February and left at Scott Base. Some minor damaged parts were returned to New Zealand for repair. During this period Pyne and Brian Smith set a series of explosions at the ice runway for K11. The explosions were intended to produce gravity waves which were recorded by K11 on the ice runway monitoring strain network. Bathymetry measurements were also made off Scott Base on a line to Mt Heine. The line extended 3km until depths greater than 560m could not be resolved.

During the period on the sea ice garbage was burned and the cans crushed by D4, bagged and returned to Scott Base for disposal. Human waste was deposited in augered holes in the sea ice.