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Blog Archive - December 200731st DecemberBy far the most successful day for radar collection we have had so far. In less than 4 hours Dan and I acquired over 20 km of data. Most importantly, however, this was an almost 100% acquisition rate. Over the previous few days we have been losing data because the transmitter signal has been turning off. We are now driving short sections (2-3 km) before checking that data is recording, rather than driving 10 km and finding that we have nothing. Andy and John surveyed the third seismic line, but we were all back in camp not long after 4 pm local time as the weather began to deteriorate due to increasing wind speeds and blowing snow. Dan has devised a cunning plan (so cunning you could pin a tail on it and call it a fox) so that we can avoid having to dismantle DELORES each night (I estimate that we can spend between 2-2.5 hours setting up and taking apart the system each day). Instead of having to disconnect the fibre optic, the antennas and the tow ropes and reel them in each night, we are now trialling a ‘washing-line’ like set-up so that each morning all we have to do is unhook the cables etc. and drive away. If this works, it could increase our available daily survey time considerably. Now the important bit: the Hogmanay celebrations. Unfortunately we don’t have any fine ales down here (no way to keep them thawed out) so we had to make do with some port and single malt tonight. John provided the top-notch culinary delights of a green Thai curry using the frozen pork steaks we had rescued from the freezer at Rothera, served with noodles. After the obligatory pub quiz, Andy rounded the evening off spectacularly by sharing out the remaining portions of Ma Lewis’ Famous Fudge cake. Always delicious, but even more so when served with a large Islay Malt! Andy has promised to share the recipe with the rest of the team. I know it is certainly one that I will be making for years to come. 30th December Today involved more radar lines for Dan and I, whilst Andy and John fired the additional shots for seismic line 2. This included a couple of the spectacular near-surface shots that blow snow several metres sky-wards when they explode. We have noticed that it is starting to get quite a bit colder again, the balmy temperatures that we have experienced over the last fortnight (we had a top temperature of -10.01 degrees C on the 20th) are starting to be replaced quite rapidly by figures comparable to the early season (-15 to –25 degrees C). Not a development we were hoping to see quite so soon! 29th December For the first time in many days, the weather was simply not good enough to work this morning, but by early evening Dan and I were able to head out and collect some more radar data whilst Andy and John dug out some of the depots that had become snowed in over the last few days. Not entirely a write-off then, and the lie-in was certainly appreciated given how hard we have all been working over the festive period! 28th December In an attempt to solve some of the glitches that beset the collection of radar data yesterday I undertook another re-wiring job on the radar receiver box. Hopefully for the last time! It was quite clear that some of the components have struggled a little with the conditions and needed to be replaced.  Whilst I was again upside down in the receiver box, the rest of the team started to drill the third and final ice core (for density measurements). I helped out during the 6-10 m section, before rescuing Dan from the dreaded drilling so that we could go out and drive some radar lines. In the meantime Andy and John were able to continue down to 15 m, after which the combined drill and ice core are simply too heavy for two people to lift without the danger of dropping it down the hole. We are saving the last 5 m for another snowy, windy day! Great to be almost finished with that task, however, despite how much of it I have managed to skive off from! 27th December Although it has been good fun getting out and doing some exercise shooting the seismic line over the last couple of days, it has been highly frustrating for me to have got the radar up and running (see the 24th December for info) and then not be able to use it for 2 days. It is a bit like a kid getting a really great present for Xmas and then not being allowed to play with it for 2 days! I haven’t had too many tantrums though, and the wait has certainly been worth it. Whilst Andy and John drilled and loaded some additional shot holes for seismic line 2, Dan and I went out and drove some radar lines uplake from camp. Needless to say there were some minor problems, but we are certainly moving forwards now in terms of the radar in comparison to earlier in the field season. Hopefully we will have enough time and good weather left to complete enough for the basic survey grid that we planned. 26th December Perhaps the most productive Boxing Day of my life! We managed to complete the second seismic line today in record time, firing the final 18 shots (of 24) by 7pm. I should explain - for each seismic shot, we measure the sound waves generated by each explosion as they return to the surface after having been reflected back upwards from interfaces at depth (i.e. the ice/lake surface interface). To do this we measure the sound waves with geophones (devices that measure the very small vibrations generated by the sound waves) at 48 different points along the length of two seismic cables (24 geophones on each cable, each cable 240 m long). We move one cable for each shot, so 24 of these 48 geophones have to be moved each time a shot is fired. Therefore, for each shot we bury 24 geophones at about a spades depth beneath the snow surface before the shot is set off. After the shot has been fired we then dig them up, moving them to the next location as we move one of the seismic cables to the next points of measurement. This means a lot of digging, walking and driving when you shoot over 4 kilometres of seismic line as we did today! Nevertheless, we were pretty motivated (particularly so after lunch) and probably averaged about 25 minutes per shot (some took as little as 20 mins!) and we were finished by 7pm. Pretty good going for Boxing Day! Like the first seismic line, Andy and John are very pleased with the quality of the data acquired and with the preliminary data. More to come on this in the New Year! 25th December Xmas Day! After opening some of our presents (we saved the ones we had bought for each other for the evening meal) we headed out to start shooting seismic line 2. We were all feeling a little sluggish after our slightly late night on Xmas Eve so we only managed 8 shots in total (6 from line 2 and the 2 additional shots from line 1). An absolute treat this evening for dinner – we had the second bag of beef bourguignon that we had been given by the chef at Rothera. Served with mash potatoes it was absolutely delicious! Compliments yet again to Cyril! Absolutely masterful. This was followed by a sizeable helping of port, some miniature bottles of drambuie (thanks Mum and Dad!), and another pub quiz. Not a brussels sprout or a scrap of turkey (not one of my favourites) in sight. Hurray! It was a relief to see that my presents for the rest of the team (various Meccano toys) went down well. I was a bit worried that we all might have seen enough of spanners and allen keys! No rest for the wicked, however, more seismic shooting tomorrow! 23rd-24th December The good (albeit a bit snowy) weather that we have had over the last few days has fortunately continued. This enabled Andy and John to get out and drill and load the second seismic line (24 shots in all) whilst Dan put up the large tent for the news team visiting us in early January and other camp stuff. At last, some positive news regarding the radar to report: it appears that I (with a lot of help from staff at BAS in Cambridge – thank you Mark and Hugh) have been able to fix the radar and have been able to acquire some moving data (evening of the 24th). Not entirely without incident (no surprise there), but we have our first few kilometres of radar data profiling a line perpendicular to the long axis of Lake Ellsworth. The lake is clearly identifiable at a depth of approximately 3.2 km, consistent with previous radar surveys. The data quality also looks extremely good with strong, deep internal reflectors down to depths of 2 km. What a relief, perhaps there will be no need to resort to the GPR. Keep your fingers crossed!  The Ellsworth Mountains looked particularly spectacular in the evening sunshine tonight (24th). All of us arrived back at camp just before midnight, so we were able to welcome in Xmas day with a malt whisky (or two) in the open air looking over towards the mountains. An excellent day all round. Unfortunately, the plan is to get up and do some work tomorrow! 22nd December Dan and John surveyed the second seismic line (located a couple of km down-lake from camp) today. Andy drilled and loaded two additional seismic shot holes on seismic line 1, which will use larger explosive charges to provide additional data regarding the various interfaces identified from the seismic reflection profiling. I continued to tinker with the radar system. If I am unable to make it work within the next few days, we will have to seriously consider giving up on it and using the GPR we have with us. This is not such good news, since it will only give us internal reflections within the ice and certainly won’t allow us to profile the ice-bed or ice-lake reflectors.  21st December Although strictly today should have been a lie-up day, we couldn’t face staying in the tent again so we opted for drilling a shallow ice core near to camp with the Pico Drill. Whilst the first 20 m ice core we drilled is for oxygen isotope measurements to give us information on the annual accumulation above Lake Ellsworth over the last 50 years (analysis to be done at BAS), the second ice core drilled today is to be sent to Martyn Tranter at Bristol University for trace element analysis. Martyn, as a group we are unanimous that you owe us at least a pint each for this one (assuming it makes it back safely), as the weather today was absolutely appalling. Cold and windy until about 30 mins after we finished, when the wind mysteriously dropped suddenly and the sun came out. Typical. At least we have recovered the second core, which means only one more day of really hard work drilling the third and final Pico hole to go (this time for density measurements). 19-20th December The winds that started yesterday afternoon have worsened, resulting in a couple more days of lie-up. The less said the better really. 17-18th December  Over the last two days we have been able to complete the firing of Subglacial Lake Ellsworth seismic reflection line number 1. The 17th was a glorious day, with lots of sunshine and clear views to the Ellsworths. It was so warm (a field season high, so far, of -11.13 degrees C!) we were working without our fleece jackets on! We managed 17 shots on the 17th and 12 on the 18th, finishing around 1700 hours local time just as the wind started to pick up again. Thankfully all this seismic shooting has meant no radar for the last couple of days. Something of a relief! 15-16th December Finally the high winds have abated and we have been able to get out and do some work. On the afternoon and evening of the 15th Andy and John went out to complete the preparation of seismic line 1, drilling and loading the final shots, returning to camp late into the night. They then shot the first three charges on the 16th after a well-deserved lie in. The radar is now partly up and running so I have been able to perform some static tests. 14th December We are still experiencing a serious hammering from the weather. We still have extremely high winds and poor visibility (40 m at best). After 5 days of very bad weather I think I might be tempted to describe the current conditions as ‘storm-like’. It is a challenge even to crawl over to Andy and John’s tent for a cup of tea! Lake Ellsworth is certainly refusing to give up her secrets easily. This is beginning to become the authentic Antarctic experience: windy, cold and stuck in a tent! Luckily, to alleviate the boredom of lie-up, we have had some excellent radio scheds from the Comms team at Rothera over the last few days. Today’s was particularly outstanding, a highly entertaining one-and-a-quarter hour tour-de-force from Trist, Crispin and very special guest Sam! This sched included news (football, cricket, financial meltdown), HF-Radio-friendly jokes and songs (including the complete performance of ‘Ernie, the fastest milkman in the west’!). Unparalleled! Thank you folks, entertainment of this kind is vitally important when you are stuck in a tent for days on end and, dare I say it, you have set high standards for years to come! You would probably struggle to find entertainment of this order on your TVs over Xmas! 13th December Neil’s recipe for lamb curry ‘Antarctic style’: 1) defrost lamb steaks (don’t ask for details, all you need to know is that this involved a sleeping bag); 2) Soak a quantity of dried onions (high in flatulence); 3) Chop lamb steaks up and fry in a little butter; 4) Drain and fry onions in lots of butter, adding curry powder and dried chilli; 5) Mix with the fried lamb, lots of tomato puree, water, garlic salt, pepper and even more butter; 6) Cook for several hours on the Primus; 7) Serve with rice, lime pickle etc.; 8) Enjoy! Although it was absolutely delicious (even if I do say so myself), it was a bit weaker and less flavoursome than the usual standard of my homemade curries (normally the type that blow your head off). I blame the quality of the curry powder (slightly past it’s best and probably a bit weak even when it was) and the absence of cardamom pods in the manfood boxes. A terrible oversight! Nevertheless, the evening turned into quite a little dinner party, with a bottle of port, and a pub quiz. Andy recited a version of ‘American Pie’ entitled ‘Antarctica Pie’, written during a particularly bad season on the Avery Plateau, when the field party suffered 60% of the time in lie-up. We are very much looking forward to his performance of the ‘Ballad of the Avery Plateau’. Less good news: Record gust for the season today: 43 knots. We are now on 40% lie-up. 10-12th December Current status: a return to lie-up conditions. This provided the opportunity for me to resurrect some DC laptop chargers that had problematic wiring (either because I hadn’t done it right in the first place, or they had snapped because they had become cold and brittle). I am beginning to think that I have missed my calling in life. Perhaps I should have become an electrician. We did actually attempt to begin some work on the morning of the 11th, but the weather deteriorated rapidly, so we accepted defeat and retired to our tents. I cooked a pasta sauce with olives, tomato puree, dried onions and lots of butter (Cyril, the chef at Rothera, would be proud!). My first proper attempt at real cooking, rather than just re-hydrated slop! On the 12th, Andy baked some of his famous bread. It was absolutely delicious, and not just because it was the first we had tasted for over a month. How he manages it in a tent with only a few small pans and a stove is beyond me. Andy’s bread inspired me to do some cooking of my own. After a few drinks this evening I promised to make a curry the next day with the lamb steaks we brought from Rothera. Unfortunately, I forgot that we had buried the steaks so that they stayed frozen (given the weather we have had this was probably a bit unnecessary). As a result, this led to me having to dig copious volumes of snow in a howling gale and blowing snow at half past two in the morning with a bellyful of whisky. Because of all the snow we have had recently, I discovered that the frozen food box was at least 1 m down. Visibility at the time was down to 25 m. Spot the crazy Scot desperate for his curry! 9th December After re-installing the DELORES software Dan and I took the radar system out to attempt to collect some moving data today. Unfortunately, we acquired absolutely nothing. It did allow us to assess how the towing system we had devised operated, however. Seems like there are no significant problems. There is always something good to report! Andy and John continued drilling and loading shot holes, managing 11 on the part of seismic line 1 to the (magnetic) south of camp today. 8th December  As is typical after a couple of days stuck in the tent due to high winds, today started with lots of digging to clear the snow drifts and allow us to get to our equipment. Obviously DELORES (our radar system) finds it hard to get going after a couple of days lie-up too, because she has decided not to work again. I have rewired the power system again, and will probably need to re-install the software (not the easiest of tasks when the CD payer of your laptop doesn’t like the cold). On a more positive note, Andy and John have managed to drill and load 13 seismic shot holes for the first seismic line today. 6th-7th December EXCELLENT DATA / TERRIBLE WEATHER: Two days of enforced lie-up have mean that I have had an opportunity to take a really good look at the snippets of static radar data that I have collected so far. We are now confident that we can pick up the bed from these data, as well as some deep (>2 km) internal reflectors within the ice. Marvellous. Once the weather has cleared up I will be in a position to start collecting some real survey data. After all the little problems that have beset the system in the initial setup phase, this is a massive relief. We managed to have a chat with Sledge India via the satellite phone this morning (it was a bad morning for HF radio comms): Ed reports that his DELORES season has gone so well so far that he and Roger are in danger of running out of fuel before the end of the season. That is a lot of radar data! We have some way to go before we can catch up with that! 5th December The weather has deteriorated a bit today, and the high winds were certainly no good for undertaking a seismic survey, so the team decided to drill a short ice core (20 m deep) with the pico drill. Luckily I still had some work to do on the radar (a very minor rewrite of the code used to convert and process the raw data followed by more static testing) so I managed to get out of the first 17 m. Unfortunately, I returned to camp at 2200 hrs, just in time for the last, and the heaviest, 3 m section. Now that’s what you call bad timing! There are lots of things that you can do whilst pico drilling to keep the spirits up. One is to sing the Talking Heads song ‘Psycho Killer’, substituting ‘Pico Driller’ in the chorus. I’m afraid the rest really weren’t bloggable. 4th December I have finally figured out the problems that have beset the radar over the last couple of days (I have discovered it helps when you can bring the components you are working on into the tent rather than trying to do it outside at –25 degrees C). The lack of an incoming signal seems to have been caused by problems with the drivers and software for the onboard computer that underpins the recording of the incoming radar signal (they worked when the radar left Cambridge!). All it took was a re-installation of the software and the drivers - problem solved. Never has one small, green, flashing LED made one man so very happy! We now appear to have an operational radar system, and I have been able to record some static radar data. Hurrah!! 
Further exciting news today: Andy and John set off the seismic test shots, which provided some excellent quality seismic data that ‘…revealed a tantalising glimpse…’. Andy and John are both very optimistic of what might now be possible in terms of the outcomes of the seismic surveys. We are now in a position to go into full-scale seismic data acquisition mode from tomorrow onwards (weather permitting). Hopefully, the radar won’t be far behind. 1st-3rd December Further (different) problems with the radar system over the last few days have kept me more than busy. You don’t want to know really. However, I have temporarily overcome some of the cold-related power problems by connecting all three solar panels (rather than just one) to the receiver system whilst in data acquisition mode. Far better news from the rest of the team, however. Andy has managed to get the hot water drill operational, and has been able to drill and prime four seismic shot holes (a variety of charges at a series of different depths) for test shooting. Dan and John have completed the installation of the GPS glaciopole network and have found and surveyed eight of the sixteen wooden stakes installed by the Chilean survey team in 2006. We seem to be up and running (and it is only early December). Hopefully the radar situation will improve soon too! | ||
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