Monday came with chilly winds and fair enough weather, good for geological digging and documentation. We had a go at our previously discovered river section within eyesight from our camp. After digging out the marine sediments in a stepwise manner, we had a very interesting sedimentation history to tell. Alternating with each other we had beds of massive clay with a lot of molluscs, suggesting slow sedimentation rate, and beds of laminated silt and clay with no molluscs, suggesting a much more rapid sedimentation. Alternating with these were thin beds of clay with a very high occurrence of pebbles and also small boulders, in turn suggesting massive sedimentation at occasions with a lot of drifting ice bergs – it was for sure an “icy” environment!
As I have been entrusted with Andrei’s gun, and fresh meat had not been around, a large flock of geese were not safe from me. I quickly interrupted logging and went for them, and a few minutes later the evening supper was secured. A lot of feathers was removed and then I prepared a goose stew from the legs, with some salami and tomato purée, and then the goose breasts for frying “a point”, supper ready for the rest of the gang supposedly arriving at around 9 in the evening. However, after satellite telephone contact at 8 PM, we got the information that they had not started from camp 5. The helicopter came in late and they judged that it was too late to start the 7 hours travel to our camp 6. So the goose dinner had to be put aside, waiting for tomorrow.
Tuesday brought strong wind in the morning, and we decided not to leave the camp with the risk of having the kitchen tent blown away. The other section that was in reach was not that important as the section from the day before turned out to be so good. Kenneth, Polina and Andrei arrived a bit after 6 o’clock after some minor disturbances; suddenly Kenneth, sailing one of the zodiacs by himself, lost track of the other boat. He climbed a small hill and saw the other boat in the far distance sailing downstream in opposite direction! After an engine problem, they lost direction and sailed back the same way as they were coming from. Easy to do when it’s cloudy and there’s no sun giving direction. Of course they realised their mistake after a while, but the whole incident cost an hour in travel time.
However, all back together again at camp 6, the goose dinner came handy. In the middle of it all, Johanna came into the tent saying that a reindeer had just gone up our toilet ravine a hundred metres away. After quickly loading the gun, a very alive reindeer was a very dead reindeer. After the quite greasy job of skinning it, cutting out back legs, front legs, the filets and liver, we suddenly had a lot of fresh meat. In the early night the skies cleared up and the temperature dropped close to zero. The mosquito season was over!
Wednesday it was time for camp shift again. A bit of sunshine in the morning, but in the afternoon cloudy and a few rain showers. The river was tricky for the first 10 km, having a lot of shallow sand bars making it hard to judge where the main channel was. And the current was slowing the boats as we now travel upstream the Logata River. After that there was a fair distance of easy travel in deep waters in the river meanders. However, the last 25 km was a struggle. The river bed started to be quite bouldery and we had to pass two rapids, of which the first was so powerful that the engines could not make it. It was man-hauling again. And one propeller got too much of close encounter with boulders and gave up. So it was just to unload and get the boat box out for spare parts. Thus it was a late arrival at base camp 7 a quarter past 11 and after travelling some 75 km, the longest distance for camp shift. Kitchen tent up a very late dinner was served at one o’clock in the night: fried reindeer filets, fried onions and bread. And a bottle of red wine to go with that. Although all very tired, it tasted wonderful!
Thursday meant reconnaissance after a somewhat later breakfast. The travel to base camp 7 had been extremely disappointing as there were actually no geologic sections exposed along the river. There was indication from Russian literature that something better was at hand a bit further upstream. However, what described we could not find exposed, but along a 4 km long river bluff we found marine sediment on top of which there were fluvial (river) sediments and on top of that “ice complex” deposits. After the first mammoth bone found at river level, the hunting of mega-fauna started, and it only took an hour to “harvest” four mammoth tusks, of which Johanna was the proud discoverer of the first one! We understood that we were in for hard work next day to come.
Johanna with a mammoth tusk. Photo: Per Möller
When Kenneth and I surveyed which ravine was best for the ice complex studies, we scouted the tip of what looked like another mammoth tusk. After digging further into the sediment pile of silt and plant debris, it was soon realized that it was not at all mammoth; it was the whole skull of a gigantic bison. Big game again! From that block of icy sediment, jaws and parts of legs and spine soon were found, indicating that the whole animal was there more or less in place where it once died on the mammoth steppe. When this was, our future datings will tell. This animal was at the base of the whole sediment sequence of some seven metres thickness. Kenneth, with help from Andrei, then got a lot of dirty job coring the frozen sediments for later DNA studies.
Mammoth tusk. Photo: Per Möller
The rest of us dug out underlying geologic units at three different localities, securing information about the geologic evolution here. If Russian previous studies being correct with a till deposited from the last glacial advance over the area – a till that we could not locate but for sure was indicated by a high frequence of many and large boulders at river level – then we have a story of a following marine stage with clays deposited close to an ice-sheet margin. After that followed erosion of the landscape when lifted above the water level and river deposition set in. From this period we had deposition of beautifully laminated sands – alternating beds showing cross bedding and ripple lamination – and with a lot dateable plant remains. This environment was later followed by deposition of ice complex sediments, which builds up vertically from inflow of windblown silt and sand, combined with water transported sediment, all deposited on vegetated land surfaces, the vegetation just moving upwards as new sediment is added on top of it. And on these former land surfaces we find the so common bones of the mega-fauna once grazing here. It for sure became a long working day; reindeer stew was served a twelve o’clock. And an hour later we could crawl into our mosquito-free tents (no more blood smears on the inner tent after killing those bastards).
Saturday, and time to shift to our last base camp. It was a cloudy, totally calm morning with the river as a mirror. Some reddish autumn colour has already developed o the valley sides; the summer is short here! A large herd of reindeer – more than a hundred – waded the river just a hundred metres downstream. This was the theme of the day, everywhere reindeers now have gathered in larger groups starting their migration southwards, wading or swimming across the Logata River. The first 35 km on the river were tricky, with a lot of hidden sand bars. But I was nice to travel at slow speed, and the skies broke up giving nice sunshine on an otherwise chilly day. Later, the river changed its mood, going deep with stone shores, and speed went up again. But this of course had its costs; we had to pass a few rapids as the gradient of the river now had increased. The last one was 200 m long with violently flowing waters, and the boat engines barely made it. We finally reached our destination at 10 o’clock in the evening after 55 km of sailing, and set up base camp 8 on the nice, flowering beach terrace above the inflow of the Syruta Yamu into the Logata River (N73°21’, E97° 37’).
Logata river. Photo: Per Möller
Sunday started with no wind at all, and some blue ribbons among the clouds, that eventually in the afternoon developed to bright sunshine on an otherwise delightfully cool day. The day’s hunt was for the illusive “Russian till”, the till that we without success has searched for around our camp 7 in the middle of the week, and that also should be exposed just within some hundreds of meters below our new camp. No success there either; however I spotted some dark sediments high up on the valley side some 5 km downstream from our camp when we travelled up here the day before. So we parked our zodiac upstream from the rapids and walked the remaining 3 km. And there, 40 m above the river it was, the most beautiful tectonically laminated till I have ever seen, something that we glacial sedimentologists call a glaciotectonite, exposed in a 3 meters high back-wall of a slump scar and lying on top of sand that was partly incorporated into the till into something that we call boudinage. My day was made! By dating sand inclusions in the till and the sand beneath the till, and by dating the marine sediments that are on top of it we now can get a maximum and a minimum age of the last glacial advance over the area, one of the goals of the expedition.
Photo: Per Möller
A perfect day of till hunting had a perfect ending; our net was full with fish, three sikh and two shir, the latter in the order of 4 kg each. The evening meal was a feast with thin-sliced, lightly salted shir with onions and olive oil, and shir caviar with lemon as starters, followed by fried shir, boiled potatoes, butter and dill, washed down with a few cans of beer. When this report is sent to Polar at 2 o’clock in the night, the sun has been just dipping it self at the horizon and is climbing again, the night is chilly – only 3 °C – and a full moon is mirroring itself in a calm Logata River.
Per Möller, Lunds universitet