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LOGISTIC REPORT TO DSIR ANTARCTIC
Mount Erebus Eruption Mechanism Study, K-044
Antarctica New Zealand
AIMS
To make a seismic refraction survey on the summit plateau of Erebus, and find if it is underlain by thick law velocity material capable of causing the previously observed 1.5 second delay to the seismic waves from strombolian explosions in the lava lake.
To continue to record the strombolian explosions seismically and by TV surveillance until the refraction survey is completed.
To remove the VUW–owned TV station, infrasonic microphones and amplifiers, and electromagnetic from the mountain, and the recording equipment from Scott Base, leaving the sites clean and tidy, and pack it up ready for installation at another volcano away from Antarctica.
PLANNING
Planning was based on providing Mr B. O'Brien with data for his own M.Sc. thesis on Erebus activity, and terminating the program before my compulsory retirement at age 65, so that I could confirm my results from Erebus at another similar volcano elsewhere. I was also concerned that I did not prejudice the programs of my International collaborators unnecessarily in withdrawing my equipment and support.
No planning problems occurred this year, except that Prof Kaminuma was unable to participate, and Brent O'Brien was invited to take his place. Special thanks ars due to the VUW Grants Committee for covering the additional expenditure.
A suggestion concerning Tekapo is that the training course program document is a valuable record of the participants, but omits first names. Even initials are hard to find.
CARGO
One cargon was sent down containing parts of the Nimbus seismograph, and as well a dismantled second cargon for the return of my equipment to New Zeal and. Space was supposed to be available in A. Pyne's returning cargon as well, but instead a third box was provided by Pat Nolan for the gel–cell batteries. The excess allowance for the Nimbus was adequate and essential.
PERSONNEL
Dr. R.R. Dibble, Bl Oriel Ave. Tawa, Wellington.
Mr. Brent O'Brien, 2–66 Burnham St. Seatoun, Wellington
Mrs. Alla Fradkin, 49/70 Nairn St, Wellington
I Wish to commend Brent O'Brien for his able and often
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strenuous work on Erebus, and his expertise with the recording computer in the Science Lab.
PREPARATIONS FOR THE FIELD
| (i) |
We were pleased to find that our Grizzly toboggan had been flown up to Fang as a training exercise at no charge to our helo hours before we arrived. Preparing for our put-in involved servicing the recording equipment in the science lab, and preparing it for augmented recording involved replacing the VUW telemetry receivers and discriminators with the NSF equipment removed to McMurdo in 1987. Bill McIntosh of S-081 had returned this to Scott Base for the purpose. (Note that the NSF equipment has University of Alaska 1abels, because it was purchased by Juergen KienIe, a foundation member of IHESS from Alaska.) We also had to prepare enough "no useful data" videotapes for reuse, and archive the digital earthquakes to disk and clear the acquisition computer so that recordings could be continuous while we were on Erebus. |
| (ii) | All the field equipment requested Was available and in good condition. Cooking oil and long plastic tent pegs were in short supply. |
| (iii) | The addition of vehicle training to survival training was a welcome improvement, and very well organised by Nick Graves. Alla Fradkin especially benefitted, and proved to be a very able driver on Erebus. |
| (iv) | Delays at Scott Base were minimal. Our put-in was only 1 day behind my planned date. |
FIELD TRANSPORT
| (i) |
NZARP Vehicles Grizzly G5 was flown up the mountain before we arrived in Antarctica, and had been selected at short notice. It was in good condition with adequate power, and we achieved al1 our objectives with it, but the brakes needed adjusting before it was safe to drive on the mountain, and no tools had been provided. Later, the brake lever came loose on the handlebar, and no clamp screw could be found. Glue had been used to 1ock the 1 ever in place. As Scott Base had previously removed the right hand brake lever, great strength and care were necessary to control the vehicle down steep slopes. We decided not to drive down the long steep hill to Fang for the flight back to Scott Base, and left G5 at the lower hut. |
| (ii) |
Helicopter operations. These were faultless, except that in spite of my letter to the Manager, Ant. Div. on 13 March 1990, listing the equipment and weights to come off Erebus, and my complaints at Tekapo that the
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Event Diary
We arrived late on 16 Nov 1990.
- Checked and serviced all IMEEMS equipment at Scott Base, and replaced the VUW telemetry receivers with NSF ones (Ray). Downloaded digital computer seismograph and printed out seismograms (Brent); Checked all video tapes, and label led those with useful recordings of eruptions and convection in the lava lake, and prepared tapes for recording while we are on Erebus (Alla).
- Attended survival school. Alla and Brent 2 days and 1 night; Ray 2nd day only on crevasses, and a toboggan shake down journey up the west side of Hut Point Peninsula, and crossing the Peninsula north of Castle Rock.
- Check all field equipment, and assemble in IMEEMS cage (Store). Every item issued by Scott Ease was unpacked, operated, and repacked. Food box contents were checked, and missing items requested and added. Frozen meat and other perishables not kept in food boxes were requested from storeman and cook. Fuel drums, tools, electronic test equipment and spares were checked and assembled in cage. All packages were labelled and weighed. Helicopter loads were listed and sorted into 1000 pound lots, to make sure that no one was "put–in" on the volcano without their tent, pack, bag, food, cooking equipment and radio.
| 23–26 Nov. |
Put–in, and acclimatizing at Fang. Flew to Fang in 2 loads. Mick and Brent walked up to replace the MACZ station seismometer, replaced the TV camera window, and brought 3 batteries down. Ray drove 85 up to the lower hut and hack, and Nick and Brent drove up with a 1oad, and left the Grizzly at the hut during this time. Alla was a bit slower to acclimatize. |
| 27 | Nov. Helo lift to lower hut. Explosives and plain det's arrive. |
| 28 | Nov. Reconnoitre seismic refraction line from CONZ station. Helo delivers electric detonators and DFA.page 4 |
| 29 |
Nov. Install refraction spread I and fire shot 1 near CONZ. Drive up to upper hut with drill, explosives and shot equipment. |
| 30 | Nov. Nick and Brent fire shots 2 & 3 in Side Crater, while Ray and Alla record them, changing to spread 2 for shot 3. |
| 1 Dec. | Nick and Brent fire shot 4 near Cones. Then all shift spread and recording tent to spread 3. Nick and Brent walk up to Side Crater to fire shot 5, and down to Cones for shot 6 to complete the survey, and finish off all the explosive. One of the Yamaha's fails, and is left near Cones. |
| 2-3 Dec. | Rest day and windy day at lower hut. Tow Yamaha from Cones to lower hut. |
| 4 Dec. | Nick Brent and Alla bring 3 more batteries down from TV station while Ray attempts to fix Yamaha magneto. No go! |
| 5-7 Dec. | Pull out electromagnetic loop wire encircling the crater, starting at the upper hut. As we near the main crater rim, the wire becomes more and more difficult to finds because it was broken and buried by bombs from the 1984 eruption. Only about 60% could be recovered. However the heavy "Spiral–4" wire and reels abandoned by NSF in 1984/5 season were much in evidence, and Nick advised Scott Base that he would remove it. Although I disagreed because it had been arranged to be done by a separate team from Scott Base at a later date, I admired Nick and Brent tremendously for digging out and carrying about 300 kg of wire, large reels and batteries across steep slopes. Alla and I helped, and also collected the Erebus crystals requested by DSIR Antarctic, and brought down the long period horizontal seismometer belonging to NIPR from El. |
| 8 Dec. | Visited the Sauna Cave discovered by Bill McIntosh a few years ago. It is an old lava tube underlying the steam source for the ice tower 470m from El in direction 199 deg E, at spot height 3569.3m on L & S map 1253. Access is via a 15m deep shaft at the base of the ice tower. The rock roof of the cave is uncomfortably hot. Air quality is good, not to wet, and 35–40 deg C. A flannel to mop up sweat, and towel to dry off with before dressing for the cold outside are necessary. Later we set out to retrieve the TV station, but the 16 day spell of fine weather ended suddenly with blowing snow and dark cloud. |
| 9-10 Dec. | Poor weather, but Cones station was visited to dismantle the VUW infrasonic microphone and bring in the transmitter bon from Cone to remove the VUW preamp/VCO. |
| 11 Dec. |
Cloud and wind at the hut, but when Cones was visited to reinstall the transmitter, the weather was seen to be good everywhere else. My radio request for Nick to set a time to start the TV station recovery was unpopular, but above Ray's Gully the weather was very good. The plan was for Alla to drive loads down Ray's Gully to the hut, but 2 trial empty-runs down the steep part proved too fast for Alla. Ray disconnected the TV components and carried most of them down, while Nick and Brent coiled up the cables, and Alla
page 5 Apply rapid thaw treatment as in the manual, and consult Scott Base, Third left finger frozen short of the first joint. Keep Brent in the heated hut, and follow manual. |
| 12-13 Dec. | Strong winds and blowing snow prevent collection of last load. Make scheduled descent on 13 Dec impossible. Reschedule on 14th, and advise weights of: Lower hut, 4+1140 lb Ant Div gear, 890 IMEEMS equip, 230 NSF retro; Fang camp and Grizzly 1000; Upper hut 400 lb NSF retro, but allowed sked is only 2 flights: 800 lb gear to S.B., and 2+390 to Fang adding 2+250 to S.B. Sort gear into flagged piles and argue priorities. Begin 24 hour weather watch. Clears at 0230 am on 13th, and Nick and I collect last load, and then go to El to remove infrasonic microphone and 2 preamp/VCO belonging to VUW. Grizzly gets a rock jammed in its track at the upper hut after Nick has descended to a photo point, and I walk down thinking the track suspension has collapsed. Advise Scott Base, then walk up and free the rock and return. We are then ready to descend and the weather is OK! |
| 14-19 Dec. | Orographic cloud cap forms and wind rises to full gale. Tears outer skin of a panel of the Jamesway roof, which we cover with a cargo net. Radio comms with Scott Base deteriorate, and VHF repeater begins to switch on and off rapidly. Set up Compac again and recharge batteries from the TV ones (2x12V in series). Nick prefers to use VHF out in the storm. Weather settles, but orographic cloud remains, with clear patches some evenings. Achieve notoriety by suggesting an evening flight! |
| 20 Dec. | Weather clearing, but amazing that Gentle 10 found its way in with only 400m visibility at the hut. Still only two flights scheduled. First is 4+0, but two more are flown, leaving most1y VUW IMEEMS equipment. Nick had the head-set, and explained the priorities. |
| 21 Dec. | Nick, Brent and Alla prepare to leave on schedule but are held over, due to the lack of a backup aircraft, until next morning. |
| 21–27 December. | Ray dismantles the Victoria University IMEEMS installation in the Science Lab, comprising the TV receiver, antennae, time coder, VCR, and the Compaq computer, monitors (2) and printer. Also the Philips FM telemetry receivers, and one rack of discriminators, and al1 the
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manuals, f1oppy disks, videotapes, and spares. He washes TV equipment from the mountain to remove acidic deposits from the volcanic gases and packs TV equipment in one cargon, VUW seismic amplifiers, discriminators, computer/monitor/printer, and microphones in another, ready for shipment to another volcano. Inevitably this takes longer, and is less perfect than planned with 3 people, especially as 3 extra flights arranged with S–081 were necessary to bring the remaining equipment down. The first in quite c1ear weather on 22 Dec. did not land due to contrailing. The second on 23 Dec. landed only at Fang, and retrieved the camp. The 3rd on 27 Dec with Phil Kyle, Nelia Dunbar, and John Alexander, brought the NSF weather station down from the summit, and the VUW equipment from the lower hut. I was able to clean and pack it before leaving for NZ that night. |
ACCIDENTS
| 26 Nov. | While driving up with a load, Nick slid 20m backwards down the mountain side above Fang camp until G5 stopped suddenly on soft snow, and overturned, throwing Nick clear, and spreading the load down the mountain side. The right handlebar required straightening, and the 1oad collected up. Ray had driven the route twice the day before, and Nick had checked it for ice, but encountered some while seeking a better route. |
| 1 Dec. | The left hand track shock absorber broke off the bogie while Ray was creeping over some exposed rocks on the plateau. A bungi-cord was used to secure the loose end, and track performance was unimpaired. |
| 13 Dec. | The throttle cable jammed twice, due partly to freezing up near the carburettor and partly to fraying at the handlebar. This increased the concern about brakes, because the throttle must be blipped when starting down a steep hil1 in order to actuate the centrifugal clutch and engine braking. |
| 13 Dec. | A head sized rock jammed between the left track and rear inner sprocket wheel, causing apparent suspension collapse. The vehicle had disturbed the rock in passing so it rolled on to the track. It needed tipping to find and extract it. |
FIELD EQUIPMENT
| (i) | All the clothing and equipment provided were of a good standard. |
| (iii) | Instant noodles and chocolate wheaten biscuits should be available for field parties. |
| (v) | The hollow pin holding the cutter on the mate auger sheared, and the cutter was lost down the hole. |
RADIO COMMUNICATIONS
| (i) | The Tait VHF and Compac radios were in good condition, except for a dead compac battery. |
| (ii) | Although Scott Base assured us that the Mt Newell repeater was working before our put–in, we could not raise Scott Base on VHP when we landed at Fang, Communications were mostly good from the 1 lower hut, except on 14–16 December when the repeater switched on and off rapidly during our transmissions. |
| (iii) | General efficiency was good, and news service well received. |
HATHERTON GEOSCIENCE LABORATORY
I am most grateful to have shared with the IMESS and IMEEMS groups the 10 years of continual use of the laboratory for recording the telemetry data from Erebus. The space and facilities made available have been excellent, and very generous. The technicians have helped immeasurably, and have made this one of the most effective volcano observatories in the world today. I hope it continues the work after I leave the program.
If I have one regret, it is that the laboratory is not visited more by members of the Scott Base staff, and by visitors from other bases. The amount of work done is appreciated by only a few. The notice prohibiting entry to the lab is the immediate cause, but a display area. in the passages would help. Perhaps some good quality displays will spin off from the International Antarctic Research Centre.
My other suggestion is that the senior technician be given a smal1 annual budget for tools and components. At present he is very poorly off relative to the engineering and communications staff, and has no hopes for improvement.