31: Allen Nutman: A lifelong love of making geological maps

In this last episode of Polar Podcasts, we hear more from Allen Nutman, Professor of Geology at the University of Wollongong in Australia, about his lifelong passion for making geological maps, focused particularly on the Nuuk region, where he has spent decades mapping some of the oldest rocks in the world.

Transcript

Transcript

31: Allen Nutman: A lifelong love of making geological maps

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.

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Allen 0:01

All of our early maps, they had to be hand-drawn. With my PhD thesis, I had 20 big maps to colour in by hand. Of course, if you excuse the pun, nothing is set in stone. The real great disadvantage about making those maps is, if next year you decided you wanted to revise the map, if the revisions were serious enough, then you had to just literally start again.

Julie 0:30

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 last episode of Polar Podcasts, we hear more from Allen Nutman, Professor of Geology at the University of Wollongong in Australia, about his lifelong passion for making geological maps, focused particularly on the Nuuk region, where he has spent decades mapping some of the oldest rocks in the world.

Allen 1:18

So, I have a love of making geological maps. I have a love of being able to walk around and develop the understanding of the geology. A geological map is where the different types of rock, where they occur are indicated. You can not only show what the different types of rocks are there, but you can also provide a whole lot of other information that you gather when you are actually walking around. It can be, for example, something particular about the minerals that you see in that rock and so on and so forth.

There are of course modern remote sensing technologies, which can actually be very remarkable in delineating some things that the human eye cannot er, see. However, when it comes down to the real basics of what rocks are here, what rocks are there, still nothing beats actually being right out on the ground, walking around and recording what you see.

Nowadays of course, because there is GPS technology, which was actually another invention of RSES.

Julie 2:35

RSES is the Research School of Earth Sciences at the Australian National University, where Allen was based for many years.

Allen 2:44

Where, even with extremely cheap instruments, you can know your position on the Earth to within one metre. So that of course is an amazing thing because er, you want to know er, not only what rocks you’re standing on, but you want to be exactly sure where you are.

When people were mapping in the 1970s, of course that technology just simply didn’t occur. It was basically, at that stage, a brainchild of somebody who was involved in developing it for the space program. But in those days, you actually had to work out where you were on the basis of visual comparison of an aerial photograph of where you were walking around and trying to fix yourself according to features that you could see on that photograph. So in, in that respect, depending on where you are, you could be again accurate to, within 5 or 10 metres. If you were on a nice complicated wiggly coastline, you could certainly fix yourself quite well, to say OK, I’m absolutely certain I’m standing exactly here. This is what the rock is. Of course, if you were in more featureless places away from a coastline then the degree of accuracy was somewhat less.

So, that was one aspect of old-style mapping is that you had to be not only geologically conscious, you actually had to be geographically conscious as well. Nowadays, you have to be geologically conscious, but you have a GPS which does the geographic thing for you.

Also once you had produced your geological map as an overlay on an aerial photograph, by literally walking across the area and recording what you could see, you then had to manually transfer that off into a, whatever best topographic map there was available at the time, in order to make a, a proper map. So that was again a process which had to be done by a combination of science and art and come up with a map. 

I have a love of being able to make a fusion between art and science of a coloured geological map that can try and express to people what is actually there. It is a fusion between art and science because of course what you put on that map should be scientifically as accurate as you possibly can be. But it is art because you’ve got to, via a combination of different colours and so on on that map, you’ve got to convey that information in the most intelligible way to anybody looking at the map. So, for example, you can make really awful maps by literally the choice of a wrong colour or colour densities on a map.

So all of our early maps, they had to be hand-drawn, of course. Hand drawn in the field and then you go through a process of compilation. That would again be hand-drawn. Generally the compilation for doing your first published colour map would be done on basically a big sheet of, for want of a better word, tracing paper – drafting film – with black ink line work.

You would then put that through something called a dyeline printer. And then, you would hand-colour the map. So I remember with my PhD thesis, I had four quite big maps related to my thesis. I had to do five copies of my thesis. Therefore I had 20 big maps to colour in by hand.

But the real great disadvantage about um, making those maps is, if next year you decided you wanted to revise the map, then if the revisions weren’t too bad you’d go back to you dyeline and very, very carefully scrape out all the sections of lines that you wanted to revise. You had to do it carefully cause if you started to make sort of any sort of irregular cuts across the plastic film, then if you started running another ink line across there, of course the ink would bead along those cross fractures. But, of course, if the revisions were serious enough, then you had to just literally start again and do a new ink drawing map. So it was a very tedious business, but one did of course still manage to produce some nice products in the end.

Allen 7:44

But there was a time, I guess, for all technologies to come to an end and in the, shall we say, middle of my career in the middle of Clark’s career, digital production of maps, digital technologies were starting to become available, to individual cartographers, geographers, geologists, rather than it simply being something only possible in very big organisations. And we’d in the late 80s, after we’d come up with the terrane model, our first terrane geology maps of the Nuuk region were the old fashion ones, hand-drawn on a the plastic sheet of paper. And then things were advancing so fast that we were having to repeatedly completely redraw the map again. And then it was Clark talking to cartographers in his university heard about this program called Freehand. And then we decided the time was to shift over and actually digitize in Freehand. And so that is how we did actually start getting out of the Stone Age and into the modern age.

So we were starting to produce these terrane maps of the region and Ole Christiansen of NunaMinerals was very interested in it and he suggested, why don’t you actually try and make a digital set of hundred thousand maps of the whole of the Nuuk region to replace the simply lithological ones, which had been produced by the survey. So he gave us a little bit of support to help with that and out of that grew a series of our versions of the GEUS or GGU

Julie 9:44

GEUS is the Geological Survey of Denmark and Greenland and GGU is its predecessor, the Geological Survey of Greenland.

Allen 9:52

one to hundred thousand maps of the Nuuk region. And then I guess about 5 years ago I thought well, why are we reproducing these areas exactly of the official published printed map sheets? Nowadays people want seamless maps. Ok some people will print them out and have them nice on their wall, but largely people are going to be looking at maps either on a computer in their office or even on a tablet when they’re in the field. And as long as it’s done with a good resolution and scalable then it makes a lot more sense to actually have as seamless as possible maps across the whole area. And that’s where we decided to actually make a seamless map of the whole of the Nuuk region geology at the scale of a hundred thousand.

And to give you some kind of idea of the size of that, at full hundred thousand scale, if you print it out, the map would be about two metres tall. So this was all hand digitized most of the clicking being done by Clark.

So um, that is how the one to hundred thousand scale seamless geological map of the whole of the Nuuk region came into being. It is a fusion of a lot of people’s work. What you see in that map, it would have been impossible for us to do entirely by ourselves. So on a lot of the maps the lithological boundaries

Julie 11:27

The boundaries between rocks of different types

Allen 11:30

have been mapped throughout the decades by many geologists who have been employed by GEUS, GGU, and so on. What we have done is, with the very large amount of geochronology we’ve done over the area and our new geological model, basically put our own slant on that by dividing all the geology up into these separate tectonostratigraphic terranes, proven via a combination of field observation in many critical places, plus also a very, very large amount of geochronological data. Most of the geochronological data in the Nuuk region, it has been supported by the good taxpayer of Australia, and to a lesser extent the taxpayer in Japan, and in even lesser extent the taxpayer in Denmark and Greenland.

So that is actually how that particular map came into being. Clark’s involvement in the geology of that is 48 years. My involvement in the geology from the time I first started at 19 as a field assistant has been 45 years. And of course there’s all the other effort expended by the contract mappers for the Greenland Survey over the years, 

Of course, if you excuse the pun, nothing is set in stone and actually in 2019, Clark and I, even though we’re getting very long in  the tooth, we are not giving up on map projects and I guess probably our final things in our careers will be even more crazy than some of the early things that we did. We intend to make a geological map of the entire west coast in Greenland.

My mother told me that even at the age of five, I was drawing imaginary maps. So obviously there’s something about me and maps and I do enjoy making maps. Not only for the sort of, shall we say, the scientific satisfaction of it, but I also want to be able to look at that map when it’s finished as a sort of a balanced work of art as well because a scientifically accurate map should also be a pleasure to look at. 

We have now produced a seamless geological map over the whole of the Nuuk region. That is a culmination of decades of work. It’s something which really I can look up on the wall and I don’t see it as a scientific geological map – of course it is. We’ve done our best stab at being accurate. What I see when I look at that map is a whole lot of personal memories come flooding back to me.

Julie 14:34

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