Mammoth tusk from sediment along the Logata River. Photo: Johanna Anjar
The week started as the last ended, with marvellous weather; blue skies with only a few cumulus clouds. Monday we took a 20 km reconnaissance trip upstream the Logata River from our base camp. Only 5 km away were some fantastic, steep and 20 m high sections in lacustrine silts and clays, which we schematically logged and took some samples from sand beds at the top for OSL dating. Another 15 km away, the same type of sediment were exposed in a meander bend. We had lunch at the site, and when Polina sat down she proclaimed “I think I am sitting on a mammoth tusk”. And right she was; we soon had dug out the most perfect and largest specimen on the expedition, measuring 1.6 metre in length and 25 cm in diameter at the base. Some other mammoth bones were soon found, all emanating from a quite thin ice complex deposit at the top of the lacustrine sediment sequence. Back at camp our net again had a good harvest of sikh and shir, meaning salted fish and caviar on toast as starters. We are becoming quite spoiled now!
Marvellous weather!
Tuesday the weather was even better, a totally calm morning giving way for a light breeze later. I spent the day in camp making sample lists on the computer, dressed in shorts and T-shirt. A few of us made some additional investigations in the till section downstream – painstaking search for and measurement of elongated stones, what we call a fabric analysis, which under best circumstances reveal the stress direction beneath a glacier and then tell in which direction the glacier moved. In the afternoon we also started the cleaning and disassembling of the zodiacs as preparation for the next day’s helicopter pick-up.
Per Möller in the boat
Wednesday morning was cloudy but warm and with a haze. There was also a peculiar smell; some said it smelled like smoke in the light breeze. But there is not much to burn up here on the tundra! Later, back in Khatanga, we learned that there were massive forest fires in southern Siberia, and that smoke for sure travelled far! In delightful pace we started to pack down the camp during the morning hours, awaiting the Mi8 pick-up scheduled at around 1 am, and it came in prompt. After loading it was 1.5 hours flight to Khatanga at 180 km an hour, and we were back to a kind of civilization. After delivering all our stuff at the storage, we went shopping for fresh stuff for our last five day’s in the field, and best of all was an ice-cold Coke in the store! To our surprise “Khatanga Hilton” – our standard airport hotel – had plenty of very warm water in the showers, and that was also a delight.
Sediments
Repacking again on Thursday and then all things driven to the kind of harbour in Khatanga were our transportation waited; one speedboat with a 115 horsepower motor for us and then a large zodiac for all our equipment. We were now aiming for a river bluff close to the small village named Novorybnoe – a Dolgan settlement of some 300-400 persons. Dolgans are the native people of the area, living in the border zone to the tree-less tundra and make a living out of hunting, fishing and having domesticated reindeers. The geologic site at Novorybnoe is described in a Russian paper from the 80’s to show three tills – meaning three separate glaciations – with marine sediments in between. If correct, this should be one of the few localities where more than one till is exposed at one and the same site, and thus a key site for resolving the glacial history with not to much of puzzle work. However, the proposed timing of these glacial events was made from pure speculation as no datings what so ever are made here. Our primary goal was thus to find and confirm the previously documented stratigraphy, that is how geologic bed after bed is put on top of each other, and then make a comprehensive sampling for age determinations of the stratigraphic units, meaning sediment sampling for OSL dating and sampling molluscs and sediments for ESR dating. Expected ages of the sediments are probably beyond the age range for radiocarbon dating, but that should of course also be tested for.
Our journey to Novorybnoe went smooth on a calm Khatanga River at 40 km an hour, though we had to make a few stops on the way to let the zodiac catch up After some 170 km we reached Novorybnoe, and set up our base camp (the 9th on our expedition) below the river bluff some 300 m up-stream from the village. Here the river is a mighty such, being approximately 4 km wide and starting to form an estuary towards the Khatanga Bay that opens into the Laptev Sea eastwards. Kitchen tent up and a few sandwiches served outside in the nice weather; the zodiac was there an hour later, and we could have a pasta dinner at around midnight.
Friday started out with nice calm weather and a bit of sun. We did a quick reconnaissance along the river bluff and all the side ravines, and found soon that our best shot was the ravine just up from our camp. Then a furious digging stated, trying to locate the previously described geologic units. Of course we were the news of the day for the locals; curious boys put millions of questions on Dolgani and Russian on whom we were, what we were doing, not easy for us non-Russians to respond on. “Njet ruski” was my standard answer, and Polina was kept busy explaining that we were neither digging for gold, nor oil, and found that it was not easy to explain – or to get them to understand – that we were digging for geologic history. Women and girls were shyer, and watched us from distance on ravine ledges, probably wondering what in the world we made us occupied with. Afternoon came with clouds and increasing wind, and field work had to be stopped in the early evening as heavy rain and came in with hard wind gusts. We had to put up more rope and fill in more sand on storm mattresses to secure the tents on the a bit exposed beach location. Soon the calm river had transformed into one with rolling waves and it felt more like camping at the ocean when lying in the tent that night, hearing the waves breaking at the shoreline.
Our camp.
Saturday and Sunday continued more or less in the same way and with the same kind of weather; mostly cloudy and with strong wind. Frequent but short rain showers and even shorter sun spells. And whatever efforts we put in to it we could not reconstruct the proposed stratigraphy. Only the middle till bed was found, whereas the lower and uppermost tills still are mysteries to us. We did not find any geologic beds that could have been misinterpreted as tills and we do believe that previous researchers working this site were good geologists, not producing a “geofantacy”. So it is just to accept; some ravines are so heavily soliflucted that it was impossible to dig in to unaffected sediment and we thus did not get total coverage of the whole height of the sediment bluffs. Another possibility is that these tills have a patchy distribution, meaning that they are not lying there totally uniform as pancake after pancake put on top of each other. However, we found the marine units that envelopes the middle till, and this should make us able to get a much better chronology of the site than that existing (or actually does not exist, it is close to wild guesses).
Just before lunch on Sunday we heard wild shooting all around, and when we looked out on the beach we saw some hundreds of reindeer running down the bluff and out into the water, chased by barking dogs and firing men. After this massacre there were dead reindeer in ravines, on the beach and out in the river. Later in the afternoon when we visited the village, most reindeer (they wouldn’t say how many were killed but my guess is some 30 to 40 animals) were skinned and brought steadily into their freezer. This is a 100 meter long tunnel drilled into the permafrost some 5 meters below ground surface, holding a summer temperature on -12°C. Of course we were able to by some meat – a whole back leg – for a reasonable price, and the evening meal was treat on “a point” roasted slices of the inner loin, boiled potatoes and carrots and the lovely, buttery juice from the meat.
Hunters.
The plan is to leave Novorybnoe for Khatanga tomorrow, but we have a problem; the wind is still pressing on and the waves go high. It is hard to get the boats loaded and out on the river. So we are stand-by during the night; there has usually been a break of the wind in the early morning hours. If this happens it will be a short night.
Per Möller, Lunds universitet