K043 : Raised Antarctic Beaches, Isostasy and Dating
Antarctica New Zealand December 1996 - January 1997
The aim of this event was to look at raised beaches along the Scott Coast from Cape Bernacchi to Dunlop Island. These features have developed since the last glacial maximum approx 18,000 years ago when the ice sheets were at their greatest extent. The weight of the overlying ice depressed the land which has been slowly rebounding after melting of the ice. While rebounding a series of beach ridges were formed.
One part of the project is to date the beach ridges and associated rock platforms by three different methods and obtaining their relative heights above sea level today. This will allow modelling of the volume and extent of the ice during the last glacial maximum.
To obtain a height above sea level today it is necessary to know where sea level was on the raised beach ridges. The second part of the project looks at the modern beach formation. Linking processes found here to features in the raised beaches should give an accurate position of sea level on the raised beaches.
The third part of the event was to use glacial striations, moraines and cosmogenic dating to work out whether the ice depressing this part of the coast came from an expansion of the Wilson Piedmont Glacier or an advancement of the Ross Ice Shelf onto the coastline.
|(i)||Application: No problems.|
|(iii)||Antarctica New Zealand staff: The staff were very helpful with requests.|
|(iii)||Maps etc: The librarians were very helpful in providing the few air photos available in the library and putting us onto other contacts.|
Pre-season training course: This could do with some revision. The weekend course in Christchurch involved a lot of lectures which did not seem to be particularly relevant. In terms of the science side of things, the brief five minute talks given to everyone is possibly all that is required to advise other science parties. At this point, if there are other groups doing science of interest this can be followed up in person.
The practical sessions were ok, but it may be preferable to ask people to do a first aid course instead of trying to teach everything in such a short length of time (Christchurch component).
An alternative bad weather option needs to be considered for the Flock Hill training. The science parties had no proper training in setting tents up in a field situation due to the bad weather which makes things more difficult in Antarctica.
|(v)||Medicals etc: These all went smoothly with no problems.|
Two boxes of equipment were shipped to Antarctica before the event. These were non-delicate equipment and very tough cardboard boxes were suitable. They arrived in Antarctica in good condition. We required excess hand carry for equipment such as computers. Getting the excess weight allowance was not a problem and went smoothly. It is suggested that it is made clear this is likely to be taken off the person so should be packed accordingly (ie. packaging around the computer).
Dr James Shulmeister, Lecturer Department of Geology, Victoria University of Wellington Wellington, New Zealand P.O. Box 600 Dr Shulmeister is the supervisor of Edward Butler and adviser to Julie Quinn. Julie Quinn, PhD Student Research School of Earth Sciences, The Australian National University Canberra, ACT 0200, Australia Edward Butler, PhD Student Antarctic Research Centre, Victoria University of Wellington Wellington, New Zealand P.O. Box 600 Peter Webb, Honours Student / field assistant Department of Geology, Victoria University of Wellington Wellington, New Zealand P.O. Box 600
5. Preparations for the Field
Despite a delay in arriving at Scott Base everything at went smoothly in the time before we went into the field. We were warmly welcomed to Scott Base and the staff were most helpful with the endless questions. Our equipment had arrived and was in order. The field training seemed to take up a great deal of the time we had due to the overnight exercise being delayed (New Years Eve). Excusing Julie Quinn from the overnight exercise allowed the science preparation to be done without a last minute panic. The equipment the party received was in good condition and it was easy to change page break our requirements after discussion with Mess. Being able to organise a resupply of frozen food with the Scott Base staff was most useful as we had difficulty keeping food frozen. This was easily done due to the helpful nature of the staff.
Parts of the field training were not particularly useful to our event (much of the snowcraft was not required as we were never on any permanent snow). However, there were other groups on our AFT who needed this training. We had a brief rundown (10 minutes) on the sea ice which was the most important part of our training. Perhaps next summer if there was a second AFT training person the crevasse part of the course could be dropped and this time spent on sea ice training. A fuller brief to the AFT people beforehand may allow this to be organised.
6. Field Transport - Aircraft Operations
Our event was supported by both American and New Zealand helicopters. We had 5 double shuttles in total, 2 by K03 and 3 by the Americans as well as other contact, such as resupply and taking rocks out of the field. We were most impressed by both crews, finding them friendly and professional in their approach. Baring one move the helicopters shut down initially to organise gear which was useful as it gave us a chance to describe where we wanted to be placed and other such details. The crews were helpful in choosing a suitable site on the ground, giving us plenty of time (considering we were only seeing it for the first time) and consequently we had excellent camp sites. When working with the American helicopters we had sling loads. No training had been given to us in New Zealand about to how to load a sling load etc. This was not a problem once the pilot had explained what he wanted but it would be a useful part of the pre-season training. A little more communication from Scott Base as to when the helicopter is arriving, should the schedule be changed, would be useful instead of us needing to contact Scott Base. This caught us out on one occasion when the weather was bad at Scott Base and we were not aware (packed up camp), only to be told later after 'calling Scott Base. Overall we were very happy with our helicopter operations.
7. Event Diary
|3 January 1997||Flown Scott Base to Marble Point in a double shuttle. Set up camp and walked around Marble Point for familiarisation. Fine, warm, S breeze.|
|4 January||From Marble Pt to Gneiss Pt, reconnaissance and initial work. Helo trip with surveyors taking air photos. Fine, calm, hot.|
|5 January||From Marble Pt to C. Bernacchi, reconnaissance and initial work. Fine, cool, light S. breeze.page break|
|6 January||Survey from Marble Pt along beach, work done on profiles AC1 and AC2. Fine, cool, light NE breeze.|
|7 January||Work in Surko St. area, surveying and profile AC4. Sunny, part cloud, light N. breeze, warm.|
|8 January||Continued AC4 profile, surveyed to Gneiss point, glacial striations on Gneiss point, pits dug at AC3. Cool/cold, S wind −10 knots, cloudy with light snow flurries, low ceiling.|
|9 January||Samples from pocket beach, Marble point, AC3 holes logged. Snowing, S wind ~15 knots, cool.|
|10 January||Samples from AC6, AC3 holes logged, glacial striations/samples from Gneiss point. Overcast, lightly snowing, calm.|
|11 January||Surveying back to Marble Pt, Glacial moraines at Hogback hill. Fine, warm, light breeze to calm.|
|12 January||Survey of Pocket beach Marble Pt, ACB4 holes dug/logged, South St glacial striation work. Snowing, S breeze 15-20 knots, cold.|
|13 January||Marble Pt transect surveyed, ACB4 holes dug, South stream section cleared. Sunny to cloudy, light wind, warm.|
|14 January||South Stream samples and section, ACB4 holes logged. Sunny, light S 0 - 2 knots breeze, warm.|
|15 January||Marble Pt transect described and sampled, hole dug and logged. Fine - overcast, light S breeze, warm.|
|16 January||Triple shuttle to Kolich Pt, camp set up and reconnaissance. Fine, calm to light NE breeze, hot.|
|17 January||Kolich Point survey and beach work. Fine, cool, light but cold S breeze.|
|18 January||Kolich Point beach section, beach surveying. Fine, calm to light NE breeze, hot.|
|19 January||Kolich Point beach section, sample collection, glacial striation work. Overcast, S breeze 5-10 knots, cool.|
|20 January||Double shuttle to Spike Cape. Camp set up and reconnaissance. Fine, some cloud, S breeze, cool.|
|21 January||Surveying Spike Cape, samples from southern platform, look at southern active beach. Fine, cool S breeze 10 knots, warm.|
|22 January||Surveying Spike Cape, samples from northern platform, holes dug on mainland. Overcast, calm, cool. Sea ice broke out from bay at Spike Cape.|
|23 January||Surveying Spike Cape, holes dug and logged on mainland. Overcast, slight N breeze, cool.|
|24 January||DV visit, TL sample and hole logging, glacial moraine /striations. Overcast/fine, cool, slight N breeze.|
|25 January||Shuttles to Dunlop Island (helicopter problems). Camp set up and reconnaissance. Light S breeze to calm, warm, overcast to fine.|
|26 January||Samples from Eastern end, surveying to the NE, beaches logged. Cool, overcast, gloomy, snowing from midday with S breeze.page break|
|27 January||Surveyed to the south, samples from top of island, beaches logged. Fine, cold S breeze 10–15 knots, cool.|
|28 January||Surveyed to West, holes dug and logged. Fine, S breeze 10 - 15 knots, cold.|
|29 January||Double shuttle back to Scott Base. High overcast, S breeze, cool.|
8. Event Map
Attached are four maps detailing camps and sites where holes were dug and rock samples taken. Also attached is a copy of a section from the USGS topographic map which has inaccuracies close to Kolich Point and between Kolich Point and Spike Cape.
We had no meteorological equipment to provide a detailed account of the weather encountered. In general the range of temperatures experienced were quite warm. On a few occasions the temperature may have reached +5° C but on most days was between −5° and 0° C. Wind chill was usually the only thing that made the temperature feel cold. We had a variety of cloud cover, with considerable variation during the day from 0/8 to 8/8. In general the coast seems to be in a fringe zone between the weather that the dry valleys and mountains receive and the weather of the Ross Sea/Ross Island area. Often this fringe zone meant the weather would look bad elsewhere while still being good over the coast. We had three spells when there was snow. These were short lived (1/2 to 1 day) and were not bad enough to hinder work to any great extent. The second snowfall put an estimated 10 - 15 cm of fresh snow (undrifted) on the ground while the others were considerably less. The weather was of little hindrance except where the snowfall covered rocks!
10. Accidents, incidents or hazards
There were no accidents during the field season.
11. Field Equipment
|(i)||Field Clothing: Overall we were happy with the field clothing issued. Some of the small clothing sizes were too large for Julie Quinn, and would be a problem for smaller females. The anoraks are not particularly useful in the field and are not very warm. It is suggested that these are not recommended over the windproof jacket. For people working on the coast it would be useful if Antarctica New Zealand suggested leather boots as well as the sorrels as footwear. The three people who took theirs found them to be a valuable addition to the boots supplied. The hats supplied were not very popular with everyone wearing their own for most of the time. The insistence of people page break wearing woollen underwear on aircraft seems a little excessive. In the event of a fire on an aircraft, should the fire be sufficient to get through the other layers it is going to be serious enough to be life threatening in other ways.|
|(ii)||Tents etc: We understand we were the last party to use the tents that were given to us. The lack of side pockets and small door in one of them was not liked. All other equipment was in excellent order and functioned well. The only thing we were not supplied with which would have been useful was waterproof groundsheets. The ground where we were camping was not frozen and consequently damp in places. Fortunately we had our own tarpaulins (for other purposes) which were used in addition to the existing groundsheet.|
Ration Boxes: Overall these are great! A few items that could be added to the boxes without great changes are some more sachets or similar to make the main meal interesting (such as "cook-in-the-pot" sachets). For milo drinkers it was disappointing to see that this is not standard in the boxes as well as tea and coffee. The additional items selected to take into the field are important in keeping variety in the food (and hence interest). We found the small bags of scroggin were not as popular as muesli bars and chocolate as they tended to burst and fill pockets/packs with peanuts etc.
The only risk with the Scott Base diet is getting fat! The few days at Scott Base were great with lots of variety and choice, all done to a high standard.
|(iv)||Specialised Equipment: The small 650 - 800 watt generator given to us was perfect. It started with no problems, usually on the first pull, and kept on running faultlessly. The poinjar was an essential piece of equipment for digging the bottom of holes. This worked really well with no problems.|
12. Radio Communication
|(i)||Equipment: We were supplied with two VHF radios and a whip. The whip was never required and hence untried. With a second battery we were able to have one of the radio's on for most of the day listening (as turned out to be useful on the odd occasion). Batteries worked well with charging from the solar panel and occasionally the generator.|
|(ii)||Reception: We had no problems talking and receiving Scott Base and hearing other field parties. The timing of skeds worked well with a sked in the evening.|
|(iii)||Scott Base: The three operators at Scott Base were excellent. Any news for us was passed on and weather and news offered. We found though that the weather forecast for field parties is not very helpful as it is an extremely localised one to Scott Base. In terms of the odd phone call out and in to the field the operators were very good at trying to get these through. The only page break thing we found frustrating was getting answers to queries. We are not sure at what point the messages got hung up but a reply on the next sked along the lines of: "the person had received the message and it is being worked on" would be helpful. Then we would not feel like we had to keep asking.|
13. Environmental Impact
See attached pages.
14. Historic Sites
While at Scott Base the historic hut at Hut Point (Scott's 1902) was visited (1 January 1997). General observations were that it has been kept in good order, both inside and out.
15. Management of Science in the Ross Dependency
This event was the first year of a two year plan of field work in the area. It was difficult for the second year to be planned well without the knowledge obtained from the first seasons field work. For a project like this I think that it is important that both seasons work is evaluated in peer review as a single event. This does not put the second seasons field work in jeopardy when the whole project requires both.
Antarctica New Zealand is in the ideal position to cater for this event, the location of Scott Base allows easy access to the ice free coast where post-glacial rebound is occurring. With the combined logistics of the Americans the potential support is far greater than anyone else could offer. The project is a joint effort between Victoria University of Wellington and The Australian National University. This is a valuable collaboration as it allows the experience and knowledge of scientists working on the same ice sheet reconstruction problem in East Antarctica to be applied to the Scott Coast to provide a more holistic approach to the problem.page break page break page break page break page break page break page break page break page break page break