Polar Podcasts

28: Bjørn Thomassen: Encounters with animals while prospecting for lead-zinc in east Greenland

January 05, 2021 Julie Hollis Season 1 Episode 28
Polar Podcasts
28: Bjørn Thomassen: Encounters with animals while prospecting for lead-zinc in east Greenland
Show Notes Transcript

In this episode, we hear more from Bjørn Thomassen, Emeritus senior scientist at the Geological Survey of Denmark and Greenland, about some of his experiences with wildlife around Flemming Fjord, in central East Greenland, while prospecting for barium, lead and zinc.


28: Bjørn Thomassen: Encounters with animals while prospecting for lead-zinc in East Greenland

Based on interviews held on September 30 – October 2, 2019 in Copenhagen, Denmark

Note: Polar Podcasts are designed to be heard. If you are able, please listen to the audio, which includes emotion and emphasis that is not evident in the transcript.


Bjørn 0:01

And there were thousands of geese. And they were making those geese noise, you know. The whole valley was full of it. And, and I remember waking up, coming out of my tent one morning and they were all gone. And it was so quiet! 

Julie 0:15

Welcome to Polar Podcasts, where you’ll hear stories from geologists who’ve spent their careers, their lives, exploring and studying the remarkable and remote geology of Greenland. Why did they become fascinated with Greenland? What were the problems and the discoveries that drove them? And what was it like working in these remote places, where few people venture, even now? I’m Julie Hollis.

In this episode, we hear more from Bjørn Thomassen, Emeritus senior scientist at the Geological Survey of Denmark and Greenland, about some of his experiences with wildlife around Fleming Fjord, in central East Greenland, while prospecting for barium, lead and zinc.

Bjørn 0:59

The geese, Canada Geese. Big, beautiful er, birds. And they er, they nest in, in the summer time, you know, they fly up from somewhere south and er, spend the summer up there. They build their nests and have their er, youngsters there. And then in the autumn they fly back and you should, when you find them, you should leave them alone when they’re nesting because, they’re at the moment when they shift their, their feathers, where they can’t fly. I like them. They’re so beautiful. And then I had an experience one year I stayed for longer time. I always tried to prolong my, my season into September. So often I stayed after the others had gone home with somebody, some company.

And we were in the beginning of September in er, the root of Fleming, of south of Fleming Fjord, the root of Wegener Halvø. There’s a large valley, Pingel Dal. And we had a camp. And apparently the geese, they were collecting, coming together there before the, the big tour south across the Atlantic. So you had this mouth of the valley and there were thousands of geese. And they were making those geese noise, you know, all the time, “NYAYAYA.” So the whole valley was full of it. And I remember waking up, coming out of my tent one morning. They were all gone. And er, it was so quiet! Then, also because it had er, started to freeze, (so) all the water, that makes (you have) sounds in the valley, there was always water running down and sounding (making) sometimes like a motor road in the distance. But no running water, no geese. Total quiet.

It’s a fantastic place, Schuchert Dal. On the west side, you have what’s called Stauning Alper.

Julie 2:41

The Stauning Alps

Bjørn 2:43

Three kilometre high peaks, alpine peaks with glaciers in between. And to the east you have the flat er, sedimentary basin, the Jameson Land Basin, which is yeah, flat and gentle and covered with vegetation. It’s green and therefore there’s a lot of musk oxen. I always think of the ice age when I see the muskox.

And the musk oxen, there’re living freely there in herds of eight to ten, moving around in the landscape. And er, when you pass them, they will stand there looking at you, half a day, moving their heads. First looking north, and an hour later when you pass by, look west, and then when we pass to the south, they will still be looking, standing and looking there, so I think they had their experience, lifetime experience seeing two prospectors, geologists, walking past.

But they’re moving around there, like deers, freely. The system is a bull will have to collect some er, some females and er, so they can rear their, their youngsters. So such a, a herd will consist of eight to ten er muskox with a bull and females and the young. And their only natural enemy, that’s the wolf. So they handle the wolf in a way, because a wolf can’t hurt a grown up muskox but can eat, attack and eat the calves. So er, their defense is to stand up in a circle with the horns outside and the youngsters in the middle. So the wolves can’t do anything. That’s very efficient. It’s not er, very efficient against hunters because you can go up and shoot (down) and they will stand there and you can shoot the whole herd. Of course, now they’re protected and we didn’t do anything but take photos. But they are very impressive animals.

Problem is with this system of er, a bull securing a lot of females is that er, they’re some bulls which have no females. So they are loners. And they’re, they’re not so friendly. They’re not satisfied with life for some reason. So they would tend to attack you if you get too near to those. You should leave those alone. But, but when you have herds, you can walk up to them and take your photos.

So we had found a large er stratabound er sedimentary deposit of barite, a

Julie 5:04

Barite is a barium sulphate mineral.

Bjørn 5:07

most extraordinary locality (Bredehorn) which I had mapped out and er, others had found it. But I spent half a summer there doing a geological mapping, scale one to two thousand, fairly detailed and sampling. And there’s the most stunning structures because what you see in, there’s a cliff down to a glacier. And you can, when you’re careful you can walk along that, it’s quite steep down. And a ten metre thick exposure of nearly pure barite. But all the structures, they’re like sediments. That means, you have bedding, (also the bedding layering) and you have cross-bedding, which is a very well known structure from, from sandstones. And load casts, and (other) classical sedimentary structures but when you bang out the sample and analyze it, (and you can make heavy and) it came out as nearly pure barium sulphate. So er, my model was: (and) nearby we have a quartz-barite vein cutting up through the sequence. And both are mineralized also with galena and sphalerite.

Julie 6:10

Galena and sphalerite are lead and zinc sulfide minerals.

Bjørn 6:14

So the model was that well this, this vein has been the feeder and when it has been hitting the limestone, a favourable host rock, it has precipitated (barite) along, along parallel to both sides, parallel with the dyke. And then I looked at the geological map and said, well, where else in the area do we have a situation er, where quartz veins – and that was the old Lauge Koch map. And Lauge Koch people, Danish state, covered this area (to make) in the thirties and forties, fifties actually, in Greenland – they put economic features on their maps, which they didn’t do in, in the geological survey in the old days, which, that was the attitude there that economic geology we leave to industry. We do the scientific investigation of Greenland, fair enough.

But anyway, I look at Lauge Koch’s map and say, where else do we have quartz veins cutting up in the upper Permian. And we had a locality just east of er, Mestersvig bay. Er, so I wanted to investigate. And I think, I can do that alone, I’m close to, to er, to the airfield. Somebody can help me, and er, just sail me over there and come and get me er, in ten days. Er, I mean, I’d done that before and this was so near, and I had a radio.

So I spent the first half of September there and walked up to the er, Oksedal to that locality and it fitted out beautifully. The quartz vein had been investigated er, earlier during the investigation for the lead zinc mine in the fifties. So it was mapped out and I could see it had been trenched. Then I went, there was a beautiful exposure there, and then I went up in the small creeks and there I had the barite, zebra barite as we called because it’s alternating er, layers or horizons white and grey, white and grey and (in) the grey there is a little dolomite. So I think it’s originally been an evaporitic sequence,

Julie 8:13

An evaporate is a rock formed by precipitation of salt minerals from evaporating water, often in shallow seas or inland lakes in desert areas.

Bjørn 8:23

rr, where the gypsum thing has gone and then it’s been very porous and permeable and solutions just think fine, we’ll, we will settle down here. So exactly the same sort of structures and mineralization as, as in er, Bredehorn.

Bredehorn is an awful location topographically. It’s er, twelve hundred metres above sea level and you can have a look over the whole of Jameson Land. But when you think of mining it’s not the best place. But this is absolutely next to, to er, the deep water and Mestersvig. So er, actually we came (come) back next year and with, with a small drill and did some drilling. So we have some, some cores and er, I made some estimated ore reserve calculation, rough estimates, with tonnage and grade. And I was alone there for ten days and I had two funny experiences.

One was I had a small tent and er, a depot outside with a tarpaulin over as you do when it rains. And there were a family of fox, a fox family. Four youngsters and they loved that tarpaulin because they could jump on it like, like human children. So that was the sound I heard every morning, the young foxes jumping on my tarpaulin. That was ok.

Then they, one day I remember, I went out in the big valley heading south from er, Mestersvig, bottom of the valley and I was going to hike up the mountainside further south. I got out. I had a rifle for security but you can’t carry a rifle in the field. Nice to have in, in the tent for security during the night. But and then I saw, just in my way, absolutely fresh polar bear prints er, footprints and it’s been freezing in the night and I could see it’s a thin ice cover and it’s been pressing the ice down there. So a few hours before there’s polar bears. We must have crossed somehow. And then I got quite scared and I headed back for my camp. I didn’t dare follow the, the bottom of the valley so I had to go up in the mountain slopes.

Another time I, when I was on my way back, I’d been hiking up on a range there up to the upper Permian. Coming down, it’d been a long day, I was tired. I was carrying a rifle. And it’s a very narrow gully and er, there was this er, lone bull, musk ox, standing there. I had to get past. And what to do? So I started to throw rocks at him. And he didn’t bother. And you know, when they’re angry they make those noises, thrashing the, like a real bull, in the ground, “MRR!” But I kept, I was so tired, so I started to fire rockets on him er, signal rockets. (And just at a certain er,) I was (quite,) ten metres away or something in (and) er, this narrow gap. At some time he understood that he should be afraid and he moved. And then he moved and he was running and I was walking down and the same time I could see him and this big flat valley, south of Mestersvig, Mestersvig valley, it’s called Deltadal. Er, he was running across the valley. And then came the, the drama because at the other side of the valley there was a herd of musk ox. Er, and in comes this bull at full speed. And what happened? The bull over there in the herd, he was standing out (and the bull there) and then they started to fight. And you know when, when bulls fight, muskox like deer, they just bang their heads against each other until one of those gets tired and finally my bull, he was thrown out and ran away. So I think he must have had a very hard day. Stones and, and rockets, and then er, had to fight with another bull.

Julie 12:16

I’m Julie Hollis and you’ve been listening to Polar Podcasts.

Julie 12:27

In the next episode, we hear more from emeritus Professor Kent Brooks about an unusual rock in east Greenland that led to years of research about the nature of the Earth’s mantle.