On the fifth day of the expedition, the target was a supraglacial moraine located near Walnumfjellet, which is the most micrometeorite rich site we have found so far. Previous moraine sampling has proved to be reasonably successful, so aiming for this moraine in particular made sense. Much to the surprise of the team members, what we found upon arrival to the site was a line of sparse rocks partially enclosed in ice, with no fine-grained material to be found. Steven and Raphael decided to take this opportunity to sample ice along the blue ice field the moraine was running along, while Matthias decided to explore the moraine further to find a micrometeorite sampling site. After walking along most of the moraine, only one suitable sampling site was found, which consisted of a centimeter-thick layer of icy fine-grained material. Upon returning to Princess Elisabeth Station, we stopped on the ridge of the Svindlandfjellet to sample more fine-grained material. Upon examination of the moraine in the laboratory, it turns out that this unique sample in surprisingly rich in micrometeorites! The sixth day of the expedition was a very demanding one, as it involved sampling ice along a steep glacier close to Wideroefjellet. But it was worth the effort, as these 22 samples will allow a better characterization of the ice dynamics in the area.
The weather was exceptionally good today, so we decided to take a long ski-doo trip to Walnumfjellet, a group of small mountains located 70 km from Princess Elisabeth Station. For this very technical trip, amongst glaciers leading to the high plateau, we were lucky to have Alain Hubert as our guide, next to Raphael. After a long ride, we eventually reached our destination, 2400 m above sea level and with wind-chill effects reaching -28°C. We quickly noticed glacially eroded summits popping out of the ice, which looked like ideal sampling sites. The cold temperature motivated us to quickly get to work, sampling a very promising looking fine-grained detritus. Promising because the surfaces of these flat summits have been stable and potentially exposed to the sky for approximately 2 million years, during which we surmise that they have been accumulating cosmic dust falling from the heaven. After sampling 5 different sites, we made our way back to the station, through steep glaciers and long stretches of icy flatland. Once back, we couldn’t hold our excitement and started looking through one of the sample. Much to our amazement, we found more than ten micrometeorites in less than 15 minutes, making this sample exceptionally rich. We can finally say that braving the cold and lack of oxygen was a small price to pay for such an exceptional find and day.
As the weather is on our side, the quest for the micrometeorites continues. On Thursday, we focus on a ridge on the Vengen Mountains. This ridge is on the southeast open to the plateau, the inner, higher part of the continent – composed purely of ice and snow, and from our previous campaign in 2013 we know these are the ideal locations to look for micrometeorites! The winds here are strong (~9 km/h), with wind-chill effects of -18˚C, and the exposed glacier shows beautiful structures. Once back at the station, with nothing more than a toothpick and an optical microscope, without washing or sieving the extracted sediment, 5 micrometeorites were extracted from one of the three samples in less than half an hour. This is highly promising!
Now that we know where to look, today (Friday the 16th) we decided to visit a moraine in the Gunnestadbreen that is exposed to the SE winds from the plateau (cf. map below). Even on this beautiful, sunshiny day, the 15 km/h winds never stop, leading to wind-chill effects of -18˚C. We don’t bother to take off the skidoo suites and go straight to work. Four different locations at the different ends of this moraine are sampled. Once back at the station, one of the deposits yields 3 very nice micrometeorites in no time. This brings the grand total to 11. Let’s keep on going at it!
Today, our colleagues Steven Goderis (VUB) and Matthias Van Ginneken (ULB) are leaving Cape Town to Antarctica. If weather permitting (as usual in Antarctica), after a short stay at the Russian air base, they will arrive on the new airfield Perseus located ~60 km away from Princess Elizabeth station. Steven and Matthias will look for micrometeorites around the Belgian station. Micrometeorites are obviously meteorites, but less than 2 mm size (more info can be found in the attached file). Because of their small size, they contain information sometimes different and thus complementary compared to meteorites. The cold and dry climate of Antarctica is ideal for preserving those fragile stones from space. They will brush cracks in rocks to collect dust, a mixture of terrestrial and extraterrestrial material. Micrometeorites will be recovered later in the lab by magnetic separation and hand-picking under microscope.
Bye, Bye the “Atmosphere Container”, and the Station PEA…
Thank you very much for your precious help, advices, availability, friendship,…!!!
I will never forget it.
From Nadine Mattielli
Before leaving the campground and going back to the station for Christophe and I, TJ managed to hang all the drawings he had received from children on the containers. All those drawings are amazing and so beautiful. A nice picture with the band!!
From Nadine Mattielli
After having completed our snow sampling and installation of the passive samplers for inorganic and organic compositions of the airborne particles, we celebrated the drilling milestone depth of 200m!! Porto on ice for everyone (or whisky…). At 9 pm, the CHASE and glaciologist teams gather into the 12 feet container for reparations, working, drinking and also eating… Antarctica, the place for cold icy immensity and warm human nearness.
From Nadine Mattielli
Saturday started with a very good weather, but quickly the white-out appears. It was then really hard to distinguish the sky from the ground. In addition, a strong “drift wind” continuously blew on the ground. This wind creates the reliefs so beautiful at the surface of the ice or the snow, but so unfriendly when you go out of your tent or have to go on field to sample. We reached the sampling site 36km away from the campground. Not easy… but finally the sun pushed away the white-out effects and we could see again our tracks in the snow.
From Nadine Mattielli