K047: Dating Relict Ice in the Dry Valleys
Antarctica New Zealand 2004/05
The ongoing aim of this project is to understand the origin and paleoenvironmental significance of relict ice from glaciers and lakes, which now lies buried by surficial sediments in many parts of the Dry Valleys. This phase of the project focuses on relict ice, buried in Lower Victoria Valley, which will be used as an analogue for relict ice in Beacon Valley. Of particular value will be the independent dating of sediments covering the ice using a new method of atmospherically derived beryllium-10.
Since the proposal was written, studies have shown that the use of atmospheric Be-10 to date Antarctic soil profiles gives equivocal results, and an independent test is needed. This requires sampling of a soil profile in a deposit of a known age. Unfortunately, such deposits are not available Lower Victoria Valley, but may possibly exist in Beacon Valley. Although we will have to wait until next season to sample such a deposit (Lower Wright Valley), Be-10 dating will be carried out on soils sampled in Beacon Valley and may give confirming dates.
In this field season, we sampled the modern environments and stratigraphically recent ice deposits in Lower Victoria Valley as well as the modern and buried ice deposits in Beacon Valley. The main aim will be to analyse the ice for percentages of O2, N2 and Ar in the occluded gas bubbles. Ratios of these gases can be used to distinguish glacial and lake ice. The gas analyses will be used in conjunction with standard chemical (6 cations and 3 anions) and stable isotopic analyses to help characterize the ice. Results from this study will not only help with interpreting the origin of the buried ice but also test Hall's (2002) lake model for Victoria Valley.
A further aim is to investigate the use of resistivity measurements for detecting massive ice and ice cemented sediment. Compared to other geophysical methods, this is a relatively simple and inexpensive method. Seismic methods will be attempted in Beacon Valley by the Marchant group (NSF program), while GPR has had limited success. Gravity measurements have been made (Sletten) but have not been processed. Thus, if resistivity methods prove to be useful, they would go a long way towards understanding the extent of buried ice in the Dry Valleys.
|Name||Designation||Organisation||Departed Chch||Returned Chch|
|Warren Dickinson||Event Leader||VUW||8 Nov 2004||14 Dec 2004|
|Dan Zwartz||Scientist||VUW||8 Nov 2004||14 Dec 2004|
|Andrew Mackintosh||Lecturer||VUW||17 Nov 2004||11 Dec 2004|
|Leigh Hyland||MSc Student||VUW||8 Nov 2004||16 Dec 2004|
Application processpage 2
The process by which event leaders are informed of support needs modification. The review committee ranked my proposal 22 out of 35 proposals reviewed. The letter went on to say that the proposals would be supported in order of their rankings until the science resources were fully allocated. Although I was given a verbal indication my event would be supported, I was never given a formal letter confirming support. From my standpoint I was in limbo and it was not 100% clear that I would receive support until I received a movements spreadsheet in early May 2004. This is not acceptable, and a formal letter of support needs to be issued to the event leader no later than mid-February for the coming season.
Communications with Antarctica New Zealand staff
Communication for event operations and planning needs improvement. Event planning cannot take place through 2 people as communication is never perfect. For example, both Keith Springer and Pete Cleary worked on my event, and several items fell through the cracks. Although the number of events may be too large for one person to handle, it would be better to split the events between two people rather than spread two people over all the events. That is each event is assigned to one ANZ staff member.
Provision of maps and aerial photographs
Maps and photos are not provided by Antarctica NZ so it remains the responsibility of the event leader to obtain these. However, much of the Dry Valleys lacks low-level, high resolution photographs. A system currently under development by the USGS will provide digital photographs and laser altimetry. This system needs to be supported by Antarctica NZ so that detailed photographs and elevations are available to NZ scientists working in the Dry Valleys.
Handbooks and info arrived in time!
Medicals, documentation and flights to Antarctica
I did not receive my environmental permit until after I had returned from the field! In addition, it needs to be made clear to scientists that it is now not possible to deviate from an event after the PEE has been processed by the ministry.
For years now, event leaders have faithfully sent scientific and logistics reports to NZAP and now Antarctica NZ. These reports contain valuable information not only for a de-brief of the past season but also to future event leaders. Although event leaders make numerous copies of these reports, to my knowledge they are only available for perusal in two places: 1) the Scott Base library which is not accessible for 8 months out of the year and 2) the Antarctica NZ library in Christchurch. Most detrimentally they are not indexed. In other words, if I were going to a particular location in the Dry Valleys, it would be extremely useful (both scientifically and environmentally) for me to know who has been there and what they have done there in the past. At present, it is difficult and time consuming (but not impossible) to find this information for NZ events. However, as far as I know, it is impossible to get this information for US events. This situation is not acceptable, and in fact, it makes it impossible to answer fully certain questions on the PEE report.page 3
Scientific reports should be indexed and made available on the web. This would not only provide valuable information for scientists but would also allow the public a further view into what happens in Antarctica. On the other hand, the logistics reports may be sensitive and probably should not be put on the web. However, they should still be index and available to event personnel. In addition, Antarctica NZ should pressure the US events to follow suit.
*PREPARATIONS FOR THE FIELD
Reception and planning for your event
Access to an indexed set of past Scientific and Logistics reports would make this much easier. Because these reports are difficult (impossible for past US events) to access, we are re-inventing the wheel in many places.
Availability and condition of equipment received
All equipment must be checked by people intending to take it into the field. This should be made clear to event personnel and extra time should be allotted for this.
Although fun, AFT is a joke and essentially a waste of time for those who have spent time in the Antarctic field. It is however, useful for those who have not been in the Antarctic field with NZ equipment. The policy should revert to the 3 yr guideline- that is, no AFT if you have been to Antarctica in the past 3 years.
Safety and Risk Management processes
It is getting a bit over the top. Keep the lawyers out of it. They make the money and cause us the work, yet we are no safer than before.
General comments about Scott Base
Good place but getting a bit crowded in the past few years. Chefs' cooking is an order of magnitude better than anyone else who has ever cooked there!
|Date||Main Activities and Location||Other Comments|
|7 NOV||Arrive in ChCh, kit-up|
|8 Mon||Depart for SB at 12:00pm C-17, ariv McM 5:15 dinner at SB; Base/AFT|
|9 Tue||WD, DZ, LH - AFT 8am; night in snow cave and tents|
|10 Wed||AFT continued||windy conditions|
|11 Thu||SB, WD, DZ, & LH pack field equipment||beautiful walk on the sea ice|
|12 Fri||SB, testing and final packing of field equipment, repacking of food boxes|
|13 Sat||SB to Victoria Valley Dunes 11am, WD, DZ & LH: set up camp; Packard||WD leaves back pack at SB!|
|14 Sun||VV, recon walk around the area||wind towards sea;|
|15 Mon||VV, Profiling relict channels below Packard Glacier||late finish; plot up data in|
|16 Tue||VV, Profiling relict channels below Packard Glacier; visit by Gary Steel in||Packard Stm flows|
|17 Wed||VV, Profiling relict channels below Packard Glacier||Temp near 0 C|
|18 Thu||VV, Profiling relict channels below Packard Glacier||plot up profile data in eve|
|19 Fri||VV, DZ, LH set up resisivity (RV-1) 500m south of Dunes; WD maps Pkard||Radio sched w/ AM; Temp 0|
|20 Sat||VV, WD & LH sample ice near RV-1; AM arrives 3p; helo photos of Vly||Helo move of core box to|
|21 Sun||VV, WD,LH,AM examine Pkard Gl/Stnm seds; DZ takes resisivity||Helo w/ Blake; cuts storge|
|22 Mon||VV, WD,LH,DZ,AM recon 'morains' sth side vly; examine 'deltas' near Lk||Back to camp against stng wind|
|23 Tue||VV, WD,LH,AM spl chaotica section DZ measures resisivity (RV-2) near||Early dinner 8pmpage 4|
|24 Wed||VV, WD,LH,AM,DZ working near chaotica section; DV visit @2pm||ANZ board and FoRST|
|25 Thu||VV, Cont splng ice up LV strm; DZ resisivity at RV-3||Ed Hillary fly-by|
|26 Fri||VV, WD,LH sipre core buried ice; AM,DZ taking resisivity measuremnts||McGowan event arivs at|
|27 Sat||VV, WD,LH sipre core buried ice & glacial ice; AM,DZ recon of Packard||AM fixes dinner|
|28 Sun||VV,WD,LH sipre core LV apron; AM,DZ splng and resisvity at Lk Vida||Late dinner|
|29 Mon||VV, WD,LH sipre core; AM,DZ splng and resisvity at Lk Vida|
|30 Tue||VV, rationalize spl cashes to storage cave||Packing for helo move|
|1 DEC||VV to BV, 3pm WD,LH helo-1 DZ,AM helo-2 @ BV by 7p; set up camp;||Light winds in BV|
|2 Thu||BV, WD,LH,DZ,AM recon central BV and up into Univ Vly; 15-20 kt||Found hndhld VHF lleft 3yr|
|3 Fri||BV, Excavated trench in Granash polygon: spled blocks of relict ice||Windy/dusty diging|
|4 Sat||BV, WD,LH,AM cont spling Granash polygon; DZ resisivity sounding at||Lite wind −6 C|
|5 Sun||BV, WD,LH,AM,DZ recon of Arena Vly; pic at Brawhm Pass||Beaut day (no wind)|
|6 Mon||BV, WD,LH,AM finish spling Granash polygon; DZ resisivity sounding||Temps –2 C getting warm in BV|
|7 Tue||BV, WD,LH,AM recon of non-granite till loc ice spl sites; DZ cont||TwinOtter flying radar at|
|8 Wed||BV, WD,LH,AM spl ice below non-granite till; DZ resisvity above camp on||Winds gusting 25 kts|
|9 Thu||BV, WD,LH sample buried ice Mullins Gl: DZ,AM resisivity work||Contact w/ Marchant event|
|10 Fri||BV to SB LH, AM 1st helo & WD,DZ on 2nd;10a start||Showers and chef|
|11 Sat||SB, cleaning, sorting & packing of field equipment; AM to Chch||Pizza & Beaker Babble talk|
|12 Sun||SB, WD,LH getting set up to subsample ice at Crary lab||Ob Hill|
|13 Mon||SB, WD,LH subsample ice at Crary lab; DZ packs equipmnt for home||Bag drag WD, DZ|
|14 Tue||SB. WD,DZ on Herc for Chch 11p; LH sampling at Crary, Tristian helps||In Welly by 9:30p|
|15 Wed||SB, LH sampling at Crary, Tristian helps|
|16 Thur||SB-Chch, LH leaves sampling complete|
EVENT MAPpage 5
For most days in the field, the weather was generally good. Field movements by helicopter were not constrained by the weather. Fieldwork was not restricted due to weather conditions at any time. However, temperatures at Victoria Valley ranged from −7°C at night to +2°C during warmer days. This seemed unseasonably warm and made it difficult to store ice samples. In addition, because of some severe winter winds there was a lack of snowdrifts near camp and around the valley in which samples could be buried and kept below –10 C until they could be sent to Scott Base. Because of this was a major problem, Blake McDavitt was flown out from Scott Base to chainsaw a storage cave in the Lower Victoria Glacier. This provided a reasonable solution to the problem, although there was minor melt water running over the entrance to the cave and the internal temperature of the cave was only –7 C. Winds were diurnal with some days of up to 25 knots.
Temperatures in Beacon Valley were about 7 degrees cooler than Victoria Valley ranging mostly from −8°C to −4°C with a few nights of −10°C. Winds were diurnal with some gusts of up to 25 knots. Warmer temperatures in the last few days of our stay required the burial of the samples in a large snowdrift where temperatures of –12 C were maintained.
*ACCIDENTS, INCIDENTS OR HAZARDS
There were no accidents or incidents during this field season.
The new sleeping bags are great. The wood food boxes need to go and should be replaced with plastic (light weight) boxes. The food this year was greatly improved from the past several seasons, keep it up! Food variety is greatly appreciated. Some medium sized tents are needed. These would be for parties of 4-5 to cook and socialize in the field. Four people cooking in a polar tent is pretty cramped. For this purpose, next season I will be looking a buying an Arctic Oven from Alaska Tent and Tarp.
VHF radio communications in the Lower Victoria Valley are excellent. However, VHF radio communications in Beacon Valley are extremely limited even with the high-gain aerial. HF communication with the Qmac was good but these radios lack portability. A satellite phone for emergency calls away from camp in Beacon Valley is probably necessary.
- Bandwidth at Scott Base is a joke. For example, I needed to download a 30 Mb powepoint file for a beaker babble talk and it would have taken 3-4hrs at night had the fibre optic cable from Arrival Heights been working. As such I was never able to get this presentation. I suggest that either bandwidth is increased or visiters travelling to Scott Base should be made aware that internet traffic with the outside world is severly limited.
|Site name||Victoria Valley Dunes, at Packard Stream|
|Site location (coordinates/description)||E 162.2020, S-773699|
|Dates occupied||13 Nov – 1 Dec 2004|
|Total days (or hours) at site||17|
|Maximum number of people at site (your event)||4|
|Total person-days (or person-hours) at site||61|
|Main activity undertaken||Measuring ground resistivity, sampling ice, surveying|
|Cumulative impacts observed||Little because most of area is on mobile sand|
|Site name||Central Beacon Valley (previously occupied camp)|
|Site location (coordinates/description)||E 162.2020, S-773699|
|Dates occupied||1 Dec – 10 Dec 2004|
|Total days (or hours) at site||9|
|Maximum number of people at site (your event)||4page 7|
|Total person-days (or person-hours) at site||36|
|Main activity undertaken||Measuring ground resistivity, sampling ice, surveying|
|Cumulative impacts observed||Campsite had been occupied numerous times in the past|
Chemicals:Not used Explosives:Not used Importation:None Interference:None Geological Material:See attached sample list below Equipment installed/left in field:None Disturbance to ice-free areas:General foot prints from walking on desert pavement Waste management:All waste was removed back to Scott Base Spills and incidents:None Other samples:None
*Differences from original Preliminary Environmental Evaluation (PEE)
The total number of samples and the total sample weight taken at each site was less than the amount (60 spls/site 100 kg/site) approved on the PEE.
Samples Taken During the Event
|Ident||Lat||Long||Location||Ice/sediment type||Type & Wt. (Kg)|
|VI1-1||−77.3721||162.227||valley floor - geophys site||clear ice pod in gravel lag||ice (10)|
|VI1a||valley floor - geophys site||clear ice pod in gravel lag||ice (0.2)|
|VI1b||valley floor - geophys site||clear ice pod in gravel lag||ice (0.2)|
|VI1c||valley floor - geophys site||clear ice pod in gravel lag||ice (0.2)|
|VI1d||valley floor - geophys site||clear ice pod in gravel lag||ice (0.2)|
|VI2a||−77.3720||162.345||Kaotica - Victoria Stream||massive clear ice||ice (0.2)|
|VI2b||Kaotica - Victoria Stream||massive clear ice||ice (0.2)|
|VI2c||Kaotica - Victoria Stream||massive clear ice||ice (0.2)|
|VI2d||Kaotica - Victoria Stream||massive clear ice (~ 1m away from a,b,c)||ice (0.2)|
|VI2e||Kaotica - Victoria Stream||massive clear ice (~ 1m away from a,b,c)||ice (0.2)|
|VI2f||Kaotica - Victoria Stream||undeformed sediment-rich ice sample||sed-rich ice (0.2)|
|VI2g||Kaotica - Victoria Stream||homogeneous sand bleb (OSL sample taken)||ice-cement sed (0.2)|
|VI2h||Kaotica - Victoria Stream||homogeneous sand bleb (OSL sample taken)||ice-cement sed (0.2)|
|VI2i||Kaotica - Victoria Stream||massive clear ice (above main outcrop)||ice (0.5)|
|VI2j||Kaotica - Victoria Stream||homogeneous sand boudin (OSL sample taken)||ice-cement sed (0.2)|
|VI2k||Kaotica - Victoria Stream||homogeneous sand boudin (OSL sample taken)||ice-cement sed (0.2)|
|VI2l||Kaotica - Victoria Stream||homogeneous sand boudin (OSL sample taken)||ice-cement sed (0.2)|
|VI3a||−77.3726||162.335||Victoria Stream downstream from (VI2)||massive, clear ice in bank||ice (0.2)|
|VI3b||Victoria Stream downstream from (VI2)||massive, clear ice in bank (few cm from a,c,d)||ice (0.2)page 8|
|VI3c||Victoria Stream downstream from (VI2)||massive, clear ice in bank||ice (0.2)|
|VI3d||Victoria Stream downstream from (VI2)||massive, clear ice in bank||ice (0.2)|
|VI4a||−77.3721||162.319||Victoria Stream downstream from (VI3)||massive, clear ice in bank||ice (0.2)|
|VI4b||Victoria Stream downstream from (VI3)||massive, clear ice in bank||ice (0.2)|
|VI4c||Victoria Stream downstream from (VI3)||massive, clear ice in bank (~1m from a,b)||ice (0.2)|
|VI5a||−77.3712||162.362||Victoria Stream upstream from VI2||massive, clear ice in bank||ice (0.2)|
|VI5b||Victoria Stream upstream from VI2||massive, clear ice in bank||ice (sed at base) (0.2)|
|VI5c||Victoria Stream upstream from VI2||massive, clear ice in bank (~5m away from a,b)||ice (sed at base) (0.2)|
|VI5d||Victoria Stream upstream from VI2||massive, clear ice in bank (~10 away from c)||ice (0.2)|
|VI6a||−77.3710||162.381||Victoria Stream upstream from VI5||massive, clear ice in bank (~4m from c)||ice (0.2)|
|VI6b||Victoria Stream upstream from VI5||massive, clear ice in bank (~4m from c)||ice (0.2)|
|VI6c||Victoria Stream upstream from VI5||ice overlain by sed. then ice (OSL + algae taken)||ice (0.2)|
|VI6d||Victoria Stream upstream from VI5||ice overlain by sed. then ice (OSL + algae taken)||ice (0.2)|
|VI6-1||Victoria Stream upstream from VI5||ice overlain by sed. then ice (OSL + algae taken)||ice (5)|
|VI7a||−77.3704||162.401||Victoria Stream upstream from VI6||massive, clear ice in bank||ice (0.2)|
|VI7b||Victoria Stream upstream from VI6||massive, clear ice in bank||ice (0.2)|
|VI8a||−77.3669||162.402||Victoria Lower Glacier front (south)||clear ice within pod of lake sed in glacier (OSL)||ice (0.2)|
|VI8-1||Victoria Lower Glacier front (south)||glacier ice||ice (5)|
|VI8-2||Victoria Lower Glacier front (south)||glacier ice||ice (5)|
|VI9-1||−77.3669||162.409||VLG apron/front (south)||ice-cored mound in apron||ice (5)|
|VI9-2||VLG apron/front (south)||ice-cored mound in front ~ 4m upslope from VI91||ice (5)|
|VI9-3||VLG apron (south)||wedged-up pro-glacial lake||ice (5)|
|VI10||−77.3626||162.355||VLG (north) geophys site||wedged-up pro-glacial lake (sed in core at 108cm)||ice (5)|
|VI11a||−77.3672||162.415||VLG (south)||ice-cored mound ~ 50m in front of glacier||ice (0.2)|
|VI11b||VLG (south)||ice-cored mound ~ 50m in front of glacier||ice (0.2)|
|VI11c||VLG (south)||ice-cored mound ~ 50m in front of glacier||ice (0.2)|
|VI12||−77.3679||162.421||VLG (south)||linear lines of ice outcropping ~ 70m in front of glacier||ice (8)|
|VI13a||−77.3677||162.384||VLG (south) stream bank||clear, massive ice (with assicated contortions)||ice (0.2)|
|VI13b||VLG (south) stream bank||clear, massive ice (with assicated contortions)||ice (0.2)|
|VI14-1||−77.3664||162.377||VLG apron (middle)||glacier apron ice||ice (5)|
|VI15-1||−77.3597||162.358||VLG (north) by ice cave||ice-cored moraine ~ 20m from glacier cliff||ice (5)|
|VI16-1||−77.3594||162.357||VLG (north) by ice cave||lake over glacier ice in ice-cored moraine||ice (5)|
|VI17-1||VLG (north) by ice cave||glacier ice from ice cliff (ice cave blocks)||ice (3)|
|VI18a||−77.3775||162.152||Victoria Stream (north) west of camp||clear, massive ice in stream bank (OSL taken)||ice (0.2)|
|VI18b||Victoria Stream (north) west of camp||clear, massive ice in stream bank (OSL taken)||ice (0.2)|
|VI18c||Victoria Stream (north) west of camp||clear, massive ice in stream bank (OSL taken)||ice (0.2)|
|VI19||−77.3603||162.190||Packard glacier cliff (west)||glacier ice from ice cliff by sed bleb||ice (3)|
|VI20||−77.3587||162.198||Packard glacier cliff (east)||glacier ice from cave behind icicles||ice (3)|
|VI21||Lake Vida ice sample||ice (3)|
|VI22||−77.3600||162.350||Victoria Stream (north) west of camp||clear, massive ice (with assicated contortions)||ice (0.2)|
|BI1a||−77.8484||160.603||Polygon by weather station||profile in shoulder||dirty ice (5)page 9|
|BI1b||Polygon by weather station||profile in shoulder - taken from below sample BI1a||dirty ice (0.2)|
|BI1c||Polygon by weather station||profile in shoulder - taken from below sample BI1a||dirty ice (0.2)|
|BI1d||Polygon by weather station||profile in shoulder - taken from below sample BI1a||dirty ice (0.2)|
|BI1e||Polygon by weather station||profile in shoulder - taken from below sample BI1a||dirty ice (0.2)|
|BI2a||−77.8484||160.603||Polygon by weather station||profile in top||ice-cemented (0.2)|
|BI2b||Polygon by weather station||profile in top (melted and refrozen)||ice-cemented (0.2)|
|BI2c||Polygon by weather station||profile in top||ice-cemented (0.2)|
|BI2d||Polygon by weather station||profile in top||ice-cemented (0.2)|
|BI2e||Polygon by weather station||profile in top||ice-cemented (0.2)|
|BI3a||−77.8484||160.603||Polygon by weather station||profile in side (clockwise from BI1 looking upvalley)||dirty ice (10)|
|BI4a||−77.8484||160.603||Polygon by weather station||profile in side (clockwise from BI3 looking upvalley)||dirty ice (10)|
|BI4b||Polygon by weather station||profile in side (clockwise from BI3 looking upvalley)||ice-cemented (5)|
|BI5||−77.8595||160.570||600m across valley from camp||profile in side||dirty ice (10)|
|BI6||−77.8560||160.556||1100m across valley from camp||profile in side||dirty ice (10)|
|BI7||−77.8532||160.547||1500m across valley from camp||profile in side||dirty ice (10)|
|BI8||−77.8844||160.560||slope up to Mullen's Valley||shoulder, by triple junction||dirty ice (10)|