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Victoria University Antarctic Research Expedition Science and Logistics Reports 1979-80: VUWAE 24

FIELD NOTES

page 40

FIELD NOTES

Event 11a

A. TRANSPORT

Major movements were by helicopter and the service was completely satisfactory. The necessity to use "opportunity basis" helo movements at times caused only minimal delays due to the competent scheduling of the Scott Base Deputy Leader (Ted Robinson). Work from base camps was done on foot and a small camp back-packed to Horseshoe Mt.

B. MAIN AREAS COVERED

Event 11a camped at Mt. Fleming from December 4 to January 2 on the same site that was occupied the previous season. Horseshoe Mountain was visited by climbing from the camp up the back of the Mt. Fleming cirque to Plateau level then walking southwestwards on blue plateau ice and moraine to Horseshoe Mt, where the three party members spent a total of four cosy nights in a two man tent. The party moved to Vanda station (by helo) for the festive season after returning to Mt. Fleming camp from Horseshoe Mt., and returned again to Mt. Fleming in late December. Early in January Event 11a moved to Shapeless Mt. camping in the large north facing cirque for five days.

C. WEATHER

The weather pattern at Mt. Fleming was similar to that experienced previously in the 1978–79 season. Katabatic winds from the polar plateau and low temperatures (averaging about −14°C (@ camp level) restricted the duration of a field day to a few hours especially when working on the exposed ridges.

Winds less than 20 knots (@ camp level) were experienced for only 1/3 of the period December 4 to 22.

Weather observations were made approximately twice daily at Mt. Fleming and Shapeless Mt. These records are summarised in Appendix III.

D. COMMUNICATIONS

In general no problems were experienced using a DSIR Compak SSB radio to communicate with Scott Base. Most communication problems we had appeared to originate from the Scott Base transceiver. A lithium cell was used with the Compak set at Horseshoe Mt., giving excellent service. Blowing snow at this camp caused a static electricity charge on the dipole aerial. This was sufficient to give a significant shock or a violent spark of 2-3 mm when earthed to the tent pole. Under these conditions even communication with Vanda Station was nearly impossible, and the radio was used for a minimum period of time. The aerial was disconnected to prevent damage to the radio when not in use in this situation.

E. LOSS/DAMAGE TO EQUIPMENT

The only damage, apart from breakages of scientific equipment, was the bending of one section of the aluminium ridge pole in an Italian Tent.

Event 11b

A. TRANSPORT

Event 11b would have used nearly all its allotted 6.5 hours helicopter time in being placed near Mt Brooke in the Coombs Hills and in Bull Pass page 41 in the Dry Valleys. However, another move to the northeastern end of the Coombs Hills became possible through "backloading" on a support flight to S. 053 (Dr. J. Annexstad, NASA) operating in the Allen Hills.

B. See Itinerary

C. WEATHER

Overall the weather conditions in the Coombs Hills ranged from poor to dismal. Out of the nine days (6th to 14th) spent in the Mt. Brooke end of the Hills four were entirely lost due to gale conditions (winds in excess of 50 knots and temperatures down to −18°C). On another one and a half days conditions were at best only marginal. At the second (lower) campsite at the northern end of Coombs Hills near the Curreen Glacier conditions were considerably better. Only one day was lost, although gale conditions made another marginal. Observations of the Mt. Brooke end of the Hills made from the northeastern (Curreen Glacier) end suggested that bad weather conditions (i.e. non working) existed in the former location when workable conditions existed in the latter.

We would strongly recommend that campsites in the Coombs Hills along the Plateau edge and near the headof the Odell Glacier be avoided. On no account should parties camp on the Upper Odell Glacier. Very strong katabatic winds would appear to be common throughout the region and in the latter area would place a party at risk.

At Bull Pass the typical Dry Valley climate was relaxing and much appreciated. Summary of weather records are presented in Appendix III.

E. LOSS/DAMAGE TO EQUIPMENT

Primus problems

The primus issued with the NZARP kitchen box was not usable in the Coombs Hills. Although tested by us and apparently O.K. at Scott Base, at 2000 m the production of carbon monoxide was profuse, the indicator becoming black within minutes. The back-up stove (an Optimus from the VUWAE store) operated safely and well at all times.

F. RECOMMENDATIONS

Equipment

Brady and McKelvey were outfitted with cold weather gear by Antarctic Division D.S.I.R. for which VUWAE paid a rental. The new D.S.I.R. issue (green) quilted jackets and the new style windproofs were much appreciated under the weather conditions encountered in the Coombs Hills. The windproof trousers do need braces, however, as they work down particularly when the pockets contain equipment, etc. Ankle tapes are also needed as it's very easy to snag a crampon spike and, and while climbing, even a projecting rock.

Further work

Every effort should be made to extend for at least one more season the search for "old" pre-Pleistocene tills and tillites, and striated pavements north of the Mawson Glacier. Particularly, this should be done in the Trinity Nunatak, Schultz Peak - Mt Armytage, and Mount Murray regions. It is appreciated that the Coombs Hills-Allan Hills area is at the limit of helicopter range for a payload of 1650 lbs. However, we feel that by adopting a much more austere (but still adequate) field ration and by pruning equipment to essentials this load for a ten day trip could be reduced to under 1000 lbs. This could be done without jeopardizing in any way the safety of the field party. Given the refueling facility at Marble Point, could not the operational range be extended so as to reach these localities at the head of and on the north side of the Mawson Glacier.

page 42

Event 11c

A. TRANSPORT - not applicable

B. MAIN AREAS COVERED

Event 11c camped at Sigrid Pond during the period December 4-13 and mapped on foot moraines in the upper and lower Pearse Valley.

C. WEATHER

Event 11c was not supplied with meteorological instruments although records of the weather conditions in Pearse were made visually and with the use of a soil thermometer. These observations were relayed to Scott Base on the morning and evening radio scheds. and are summarised in Appendix III.

Event 11c experienced excellent weather conditioning during their stay (Dec. 8 - 13) in Pearse Valley. The wind was never greater than 25 knots and temperatures were warm enough to melt surface ice of Sigrid Pond.

D. COMMUNICATIONS

A Labgear radio was used and generally gave no problems in communications with Scott Base. On two separate days relay via Vanda Station was necessary due to poor radio conditions at Scott Base.

Two batteries were picked up together with a radio from the Scott Base Post Office. In the field, one battery was found to be dead even though the Post Office had given the assurance that both were fully charged. Problems could have been experienced without a spare battery if the planned field duration had been longer.

E. LOSS/DAMAGE TO EQUIPMENT - not applicable

F. RECOMMENDATIONS

It is necessary for pre-field checks to be carried out on both the radio transmitter and spare batteries.

The supply of tent pegs at Scott Base was nonexistent when 11c was preparing to leave for the field. Makeshift pegs were prepared at Scott Base for use at the Sigrid Pond campsite where suitable rocks were known not to be available. A greater number of tent pegs and ice screws (for ice camps) should be held at Scott Base for tent pitching purposes.

Event 12

(Note: Event 12 was based on USCG icebreaker "Glacier". Field notes are therefore not presented as for other Scott Base supported field events.)

WEATHER AND SEA CONDITIONS

Fine weather and calm seas were experienced throughout the survey. Temperatures were rather low for the time of year (min. −15°C). The sea ice had broken out from most of the Sound except on the western side. The surveys were prevented in New Harbour and Granite Harbour by very close pack ice.

page 43

OPERATIONAL PROBLEMS

Icing of the pressurised air system of the airgun, and ship generated electrical noise, were the main problems. Despite siting the compressor in the wet lab. corridor for warmth, freezing of the airline between compressor and firing board, and also at the firing board itself regularly occurred. This problem was partially overcome by running an electrical heater near the firing board. Both the seismic arrays and the magnetometer were subject to electrical noise pickup, which in the case of the magnetometer resulted in the collection of very little useful data. Apart from 60 Hz noise, intermittent noise from motor drives and other sources, and radio transmissions caused interference problems at times. However, it will be possible to remove most of this noise from the seismic data on replay of the tapes.

Event 13

A. TRANSPORT

On Taylor Glacier 180 km of travel was completed with Snowtric toboggan 016 in the region between Finger Mountain and the vicinity of Lake Joyce. Generally travel was with a very lightly laden sledge except for the move from Camp I to Camp II where a 250 kg load was hauled.

The Briggs and Stratton motor started and ran well until a bearing in the centrifugal clutch seized near the end of projected glacier travel. A small disc to prevent direct air entry to the carburettor was lost and had to be replaced after the second day.

The tobaggan being designed to run on snow did not travel particularly well over the rough scalloped ice on the lower Taylor Glacier. On two occasions bolts were sheared in the front suspension and once the right rear axle came loose and was dragged by the track to jam against the front axle.

B. MAIN AREAS COVERED

A gravity survey was completed from the head of the Taylor Glacier near Northwest Mountain to the sea. Travel on the glacier was by tobaggan. Walking traverses were made down the Pearse Valley and in that part of the Taylor Valley below the glacier. Camps were made on the Taylor Glacier at the head of the Pearse Valley and near Lake Joyce. From Lake Joyce the party was moved to a camp at the snout of the Howard Glacier. The party was put in on 8.12.73 and taken out on 24.12.79.

C. WEATHER

Systematic weather observations were not made. No severe storms were experienced but about three of the seventeen days in the field were spent confined to the tent due to winds exceeding an estimated 30 knots.

D. COMMUNICATIONS

Morning and evening scheds were maintained with Scott Base except occasionally when the party was away from camp making surveys at the time of the 1830 sched. Communication from Scott Base was almost invariably excellent but on one occasion transmissions to Scott Base had to be relayed via Vanda.

E. LOSS/DAMAGE TO EQUIPMENT

The radio aerial was broken near one end due to it becoming embedded in glacier ice but all was recovered, temporarily repaired and returned to the Post Office.

As mentioned above various mishaps befell the toboggan.

page 44

F. RECOMMENDATIONS

(i) A better selection of spare parts should be provided for the toboggans. A supply of nuts, bolts and locking washers is essential.

(ii) It appears that the roller bearing in the clutch should be lubricated occasionally. This was unknown to us and should be made known to future tobogganers.