Polar Podcasts

17: Allen Nutman: “Paired for life” – the beginning of a career mapping the oldest rocks in the world

October 20, 2020 Julie Hollis Season 1 Episode 17
Polar Podcasts
17: Allen Nutman: “Paired for life” – the beginning of a career mapping the oldest rocks in the world
Show Notes Transcript

In this episode we hear from Allen Nutman, Professor of Geology at the University of Wollongong in Australia, about his early years working as a field assistant in Greenland while studying geology at Exeter University, which led him to work for the Geological Survey of Greenland and later, to life-long research collaborations with two other geologists, particularly focused on some of the oldest rocks on Earth.

Transcript

17: Allen Nutman: “Paired for life” – the beginning of a career mapping the oldest rocks in the world

Based on interviews held on August 23–24, 2019 in Nuuk, Greenland

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.

________________________

Allen 0:01

Certainly conditions were very er, different in the field then as compared to now. Basically, we were left on our own for the best part of three months. We had one geologist and a field assistant. So basically, field assistants were, you know, paired with a, a geologist for life, shall we say.

Julie 0:22

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 from Allen Nutman, Professor of Geology at the University of Wollongong in Australia, about his early years working as a field assistant in Greenland while studying geology at Exeter University, which led him to work for the Geological Survey of Greenland and later, to life-long research collaborations with two other geologists, particularly focused on some of the oldest rocks on Earth.

Allen 1:15

In the later years of high school, I was wondering what to do with my life, and then I saw a program on BBC TV which was called The Restless Earth. And I can only, nowadays, remember two little snippets. One was this snippet about this crazy New Zealander, who had found these amazingly ancient rocks in Greenland and I remember a scene of him being filmed in a jolle approaching the outcrops and then explaining a little bit about it. The other image I can remember was that photograph of somebody er, sitting somewhere very high up in the Alps, sketching, tectonic structures. And really those two images, one of Vic McGregor in Greenland and somebody on the top of the Alps, I decided, I want to be a geologist.

In the UK system you could make five applications. Of those applications, four universities turned me down flat and the only university that offered me a place was Exeter University. And I remember in the interview, being told, ‘Oh, we actually have a mapping project in Greenland and we take undergraduate students along as mapping assistants’. And I thought, oh that sounds really great. So anyway, I started at Exeter. I came first in the sort of mid-session exams and then I was invited to go to Greenland as a field assistant at the tender age of 19. So that’s how I first really got in to Greenland. It was the Buksefjorden mapping project being run by the Greenland survey, just south of Nuuk, being serviced by a GGU base camp down in Midgaard. 

Julie 3:02

GGU is an acronym for the Geological Survey of Greenland

Allen 3:07

Certainly, conditions were very er, different in the field then as compared to now. Basically we were left on our own for best part of three months. We had one geologist and a field assistant. So one actually became extremely sensitive to other people’s little idiosyncracies after three months. So basically, field assistants were, you know, paired with a, a geologist for life, shall we say.

We had two single-skinned tents, which were actually more suitable for summer camping in Denmark than Greenland. You had this little yellow tent and you had a somewhat bigger white tent. And it just simply wasn’t practical to have different people sleeping in different tents. So one either used the big white tent as a sort of joint both sleeping and living tent and the kitchen was in the little yellow tent with stores. Or one was sometimes, just simply sleep in the little yellow tent and then have a sort kitchen-living in the bigger white tent.

I can certainly remember at night in storms being out in my underpants trying to tie on guy ropes again because between the guy ropes and the and the canvas of the tent there were these little plastic rings and if you had a big gust of wind these little plastic rings would snap. And then basically the guy rope would become detached and of course the tent would then start billowing in. So if  you have a nice sheltered coastal campsite it’s fine. But certainly in the higher areas it was certainly not so good things to have. Our emergency equipment consisted of a tarpaulin to get under if the tents, blew down.

The normal environment in those days when one was working with the Greenland survey is that if you’re inland, you would have camps nominally for about a week at a time. The idea was that you were put in by helicopter and then you’d access as much of the geology as you can within walking distance of that camp. There was a radio back to base camp. On the actual frequency you’d often have bizarrely interference coming from a radio station from an African country. So I distinctly remember, for example, hearing Feiko Kalsbeek, who was the leader of the base camp in Midgaard, the sound of bongo drums in the background. So it was just one of these weird freaks of the ionosphere.

On the camp radios you actually had to put out a very long aerial and you had two poles, which you had to put up, and then the aerial was strung in between and then the lead off from the aerial went into the tent for the radio. And this comes on toe the subject of Arctic foxes. Arctic foxes have some bizarre fetish regarding copper wire. And I don’t know how they know that there is a copper wire hanging up there somewhere. But it was on several occasions you’d have an Arctic fox actually bringing down one of the supporting poles just to get at the copper wire and chew it. The other thing about Arctic foxes is that you never left your soap or toothpaste outside of the tent because again they had a lovely penchant for soap and toothpaste.

There were these two calls. In the morning call, every camp was called to make sure everybody was ok and there’d be an evening call from the basecamp, everybody checking in to make sure that everything was alright. Particularly the evening calls there’d be a bit of transaction so if somebody was planning on being moved the next day then there would be sort of information approximately when the helicopters would be turning up. Food orders would be put in, which leads me off into the other subject, which is the food.

Shall we say, the food was not the best. There were food boxes, which were supposed to last two people you know for six days. And there was an A box, a B box, and a C box. And in the field season you went in a rotation through that. Some of the food boxes were more than a year old. So that, for example, all packaged rye bread in it had gone mouldy. We used to have some really weird and disgusting stuff. I remember we had this, what was supposedly corned beef from the People’s Republic of China, which I guess was almost inedible, and we used to call it basically the Cultural Revolution [laughs]. The idea that you know, people that had been killed, that’s what had happened to them. There was the, what was nominally supposed to be Russian tuna, which we used to call cardboard in motoroil. It was just awful. So this was you know, all through the 70s, boxes were really awful. 

So after two and a half to three months of that, I was actually not put off at all. And then on the second year, end of second year at university, I was also chosen, to come along as a field assistant in the same project, and then after that, there was one PhD position, left on that particular project. And I was, offered that PhD project, which was to, focus entirely on the early Archean rocks

Julie 8:41

That is rocks older than 3.6 billion years.

Allen 8:45

And, by today’s standards, undertake some very primitive geochemical, investigations. So I started that in 1976. And we had 2 field seasons – 76 and 77. And it was actually at the end of the 1976 field season that two long-standing working relationships started, because when I’d finished my obligations for the Greenland survey, I was then met up with Vic McGregor on his boat and there was this other English guy on the boat called Clark Friend. And basically I remained a collaborator with Vic McGregor up to his death in 2000, and as I speak now, I’m still a collaborator with Clark Friend. So we’ve been collaborating together for 43 years, which may be approaching some Guinness Book of Records for scientific collaborators.

And then in 1978, there was what was called a NATO advanced studies field workshop on the old rocks just south of Nuuk. And I was invited along as a, one of the field guides because, some of the sites we visited were actually on my PhD area. And one thing led to the other and out of that I ended up being offered a combined Geological Survey of Greenland plus Royal Society of London research fellowship, once my PhD was completed. And that research fellowship was to focus on Isua.

Julie 10:24

Isua is a large area that borders the ice cap inland Nnortheastof Nuuk, which comprises the largest extent of the most ancient rocks on Earth – rocks that are almost 4 billion years old.

Allen 10:37

It had been realized that, of course, over the past eight years or so that Isua was an extremely special place, unique in the world. Despite a lot of intensive research around the world, it is still a unique place in the world in terms of the fidelity of some of the information one can get about the very early Earth.

So, although there had been, shall we say, a preliminary geological map of the area made by a survey geologist called Jan Allart, it was realized that actually a much more detailed map was required of this very special geological area.

So there were two strands to that postgraduate research fellowship. One was contractual obligations to the Greenland Survey to make a much more detailed map of not only the Isua supracrustal belt, but also the adjacent areas dominated by gneisses, which had literally been untouched, apart from a few spot landings and an occasional walk out from the Isua Supracrustal belt. And the other obligation of course was research into the Isua Supracrustal belt. That lasted for two years.

I then returned umemployed to the UK. And then what happened after I’d been there a couple of months – it seems very quaint these days – a letter arrived from the Greenland Survey saying, regrettably, due to the tragic death, of Jan Allart, that they wanted in 1982, for me to continue, the mapping out from the immediate Isua, area. So I ended up getting a Carlsberg Fund short term fellowship for about one and a half years, where I returned to Copenhagen and I was involved in producing a one to forty-thousand scale map of Isua, with a accompanying eighty-page bulletin.

So that was the um, end of that particular era. All options had run out, based in Copenhagen, and at that stage I moved over to St Johns in Canada because I had, in a summer off from Greenland, in 1983 actually been working on the early Archean in Labrador, which is basically a continuation of the geology in west Greenland. So that project continued in a entirely laboratory fashion, but I couldn’t wrench myself away from Greenland.

Moving over to Canada, St John’s Memorial University in Newfoundland. Of course in the same province you have Labrador snd in northern Labrador you have bits of little slivers of er, very old crust as well, which I had already spent one field season on. So having made a sort of big move across the Atlantic, why did I continue, or wish to continue, working on the Greenland stuff? I guess because one felt that one was at a really exciting point in the studies of the Greenland stuff that one just didn’t simply want to walk away from. In that respect, I’m not talking so much about the early Archean, at this stage, but actually at the stage we were at in looking at the way tectonics worked in the Archean, particularly the tectonostratigraphic terrane model that we were starting to build up, from the previous field season.

Julie 14:11

The terrane model Allen refers to is the idea that the rocks in the Nuuk area, although most of them appear superficially quite similar, actually once formed parts of distinct small continents that stretch back in age to the earliest history of the Earth and collided with each other about 2.7 billion years ago. Untangling the puzzle of how many distinct small continents there were, the nature of their different ages and histories, and mapping them out would prove to be a lifetime of work.

Allen 14:43

So, I think that’s one reason. Of course another very important reason is one had such a good working relationship with the people who were also working in Greenland. So altogether, I decided not to abandon Greenland, but instead continue.

There was also logistically a little bit easier than one would think, that one didn’t have to um, go all the way back over the Atlantic, get on a plane in Copenhagen or, or whatever, but by one way or another, I actually managed to get onto American military transport planes, which used to in those days come up to Søndre Strom or Kangerlussuaq.

Julie 15:25

Søndre Strømfjord, or Kangerlussuaq in Greenlandic, is the name of the old American military base and the current international airport in West Greenland

Allen 15:35

So what I had to do there was to find my way to get a flight to a place called Goose Bay in Labrador and then, brandishing the right bit of paper, I was actually able to get on to military transport planes from Labrador into Greenland. Of course you had to go through the military base in Søndre Stromfjord and of course the military like the pecking order to be exactly right. So because I was a junior scientist, I was afforded the military rank of captain in the American air force, just so that everybody knew on what sort of level [laughs] I was on. So that meant that you could go to the, you know, the officers’ mess as opposed to the non-officers’ mess. So that was also a little bit of a bizarre thing. So that’s how I was able to get over to Greenland and continue work. So in 1985 I went over that way, 1987 and 1988.

There was a very, very big controversy going on in geology at that time. Should one believe what, what expert field geologists or should you believe what the isotope geochemists are telling us? Because there were some rocks where we believed that these particular rocks were very ancient, based on their field characteristics. On the other hand, isotope geochemists from Oxford, they were presenting isotopic evidence to show that actually these rocks were much younger. So there was, if you like, a complete, divide of diametrically opposed views about what the field geologists were saying and also what the isotope geologists were saying. We knew we actually had to do a lot more detailed work.

Julie 17:33

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

Julie 17:42

In the next episode, we hear more from emeritus senior scientist Agnete Steenfelt about introducing a stream sediment sampling program to Greenland, which would grow to decades of work and tens of thousands of samples.