Dan McKenzie interviewed by Alan Macfarlane 11th May 2007

0:05:23 Born in Cheltenham 1942; grandfather was a well known doctor in Harley Street; my father went to Highgate School and then to Caius and also became an ear, nose and throat surgeon like his father; during the war he was in the R.A F. and I was brought up as a small child in the house where John Hampden refused to pay Ship Tax in Buckinghamshire; when my parents found it it was in terrible repair and falling down but it was a very beautiful Elizabethan house; they rented it and could not do any refurbishment; left there at seven and moved to London; before that went to a girls' school in Aylesbury; in London lived above my father's consulting room in Harley Street; went to a private school in Kensington; mother's background was completely different; she was brought up in Leeds and father was a labourer; she got a State Scholarship and applied to come to Newnham to read English; at her interview made her read aloud which emphasized her Yorkshire accent and turned her down; she never forgave this snobbery; instead she went to Royal Holloway but had friends at Cambridge; when I remember her she had no accent, her Yorkshire accent had just gradually disappeared

7:21:05 Went to Westminster Under school then Westminster itself; had a grand public school education with extremely bright teachers; until puberty I was hopeless; vividly remembered the change when I suddenly discovered physics and chemistry and to some degree biology and after that never looked back; younger brother who had been considered the bright child found me going from bottom of the class to top; there were two maths teachers and a physics teacher of importance; one maths teacher was a German refugee, Adolf Prague, who was terrific and taught pure maths; the other was Fisher who taught applied maths; Austin Stokoe taught physics but I adored chemistry as it was so logical; top in both physics and chemistry year after year; got a major scholarship to King's on basis of this success; came to King's because Austin Stokoe still had friends here; he wrote to one of them saying they should interview me; interviewed before I had any results by John Raven; spent an hour talking about Dostoevsky's novels and the orchids of the chalk and on the basis of this he gave me a place in King's to read physics

13:07:10 Unremembered incident about religious beliefs at school; very much influenced by my mother, my father less; father particularly good at languages and did rather belatedly try to encourage me to become a doctor; my mother was very interested in landscape planning and geology; she was a very forceful character; she got breast cancer while I was at school which was successfully operated on and did not recur but when I was an undergraduate she got cancer of the womb which was not operable; she had got an honorary degree in landscape architecture on the basis of a book 'New Lives, New Landscapes' which became the standard textbook; she was extremely encouraging and interested in my intellectual life

18:27:10 School had more effect on my than me time as an undergraduate ; after getting a scholarship to King's decided to stay at Westminster for a year and to become a mathematician as the teaching was so good, probably better than at Cambridge; at the end of that year got another scholarship in mathematics; at the same time got politically very active with the fairly violent left wing; also rowed like Pat Bateson who was also at Westminster; then came up to Cambridge and found politics here half-baked and right wing so had no interest in politics here; parents absolutely old Labour because of the Welfare State which my father had joined as soon as it started; real delight of Cambridge was that so many of the major figures in their subject were here lecturing to undergraduates; went to Dirac's lectures and Hoyle's; found the natural sciences tripos rather easy so went to all kinds of lectures right across the sciences; lucky to get a first at the end as my heart was not in it; came up to be a chemist but started geology in preference to physiology which had been taught at Westminster; had read Darwin and Lyell with total fascination but the course here was awful with no intellectual interest; did maths and physics which I liked but gradually realized that the part of physics which really excited me was what had happened before the war and not what people were doing then; particularly interested in quantum mechanics, Dirac's work; in my third year Maurice Hill was my director of studies; also knew Drummond Matthews who was a research fellow; they decided to turn me into a geophysicist; sent me to see Teddy Bullard as I was too theoretically inclined for either of them; became his graduate student; got a 2:1 in final degree in physics, a reflection of my increasing disinterest in what I was being taught

27:25:21 As a graduate student, Teddy suggested the subject of thermodynamic variables for research, on the basis of which got a research fellowship at King's College at the beginning of my second year; mother had read the dissertation and had given guidance on presentation which has stood me in terrific stead ever since; this changed my life completely as I could do what I wanted; gave up doing what Teddy had suggested and got interested in how does the interior of the earth convect which was completely speculative at that time; taught myself fluid mechanics and went off to Scripps at the University of California, San Diego, having got very bored with Cambridge at that time, on the invitation of Freeman Gilbert and Walter Munk; in those days there was lots of money for research, especially as the American Navy was extremely interested in anything to do with deep sea oceanography; knew nothing about how to go to the States and get paid so went to the Embassy and got an immigration visa; did not realize that this would mean I was liable for the draft; received registration papers at the end of six months; this was the time of the Vietnam war so I got on a plane and came home; but nothing in my early life as a scientist had such a profound effect as those eight months in California; it was a completely different world where no one was interested in my background but simply in me as an intellectual scientist

34:31:00 Came back to Cambridge and wrote a PhD informed by the time in California; went back to America and took up a fellowship at Caltech; as my visa was of a different sort I was not expected to do military service; just after I submitted my PhD in 1966 Teddy was invited to a conference in New York which was called 'The History of the Earth's Crust' and he suggested that they should invite me as well; this was the beginning of the complete revolution as there were two people, Fred Vine, who had been an undergraduate a year ahead of me at Cambridge, and Lynn Sykes gave talks showing that without any doubt at all data showed that the continents were moving, and they weren't looking at the continents but looking at the oceans, looking at the processes which happened on spreading ridges which produced magnetic anomalies and earthquakes; came back completely convinced what I should do and did my first paper on plate tectonics looking at the thermal structure of the oceanic plates as they were formed and cooled; this was done between coming back and being examined for my PhD and ended up being one of the earliest papers on the whole of this subject and was published in 1967; it needed the maths and physics I had been taught as an undergraduate and used an approach I'd learnt from the fluid dynamicists who do everything in terms of dimensionless variables which is totally opaque to everybody else but is an extremely powerful way of thinking about things; this was the first use of this in solid earth geophysics; all mathematics and analytical and all done in five pages but the computation and pictures left until I was at Caltech and that was a huge undertaking at that time

39:50:21 Caltech Seismological Laboratory, which is in the granite hills where it was possible to record earthquakes, was  a wonderful environment with a small group of people who knew each other well and were doing absolutely first class seismology; that was when I became an earthquake seismologist; earthquakes are wonderful as they not only propagate through the earth but are also generated by the plate motions so you have two things, the structure and the mechanism that makes them; only stayed there six months then went back to Scripps for a further six months; there decided to read all the papers on plate tectonics; read one of Teddy Bullard's which had been written while I was a graduate student on how to do continental reconstructions; he used a theorem by Euler; reading his paper made me think it was the obvious way to think about all these global motions and turned the magnetic anomalies and earthquakes into a really precise mathematical theory; wrote this up over a weekend with Bob Parker. He had a program that would do mapping from a sphere to a plane in any projection that you chose; we put this together and sent the paper to 'Nature'; we finished the paper on a Saturday in October 1967  and went down to the main post office to send it off and found it shut; got quarters and fed the stamp machine until we had enough to send it airmail to the U.K.; Herbert Huppert's wife Felicia remembers meeting us just after we'd done this and us being very happy and pleased to have got it off; heard nothing from 'Nature' and got no referees reports and it was published in the last issue of the year in December 1967 which meant that our paper was dated that year rather than everybody else's which was dated 1968; this was a piece of luck as what then happened was that I heard that Jason Morgan on the East Coast had actually had the same idea and it turned out later on that he had actually talked about it at the A.G.U. Conference in the Spring where I had been; it so happened that I had not thought much of the abstract of his talk and had gone to another session; he didn't talk about his abstract at all but about plate tectonics; nobody understood his paper but Xavier Le Pichon; he was French, working at Lamont, and went back and secretly worked flat out to do all the reconstructions using these ideas and said nothing to anyone, as Lamont, the research laboratory at Columbia University is big, secretive and extremely competitive; I knew nothing about this until much later; so what I did was independent but 3-4 months later than Jason Morgan at Princeton; it has been alleged that I heard his talk; curious how a lot of the ideas of plate tectonics were discovered by two people working independently at the same time; left Scripps to spend 3-4 months at Lamont; at Lamont discovered that everybody was working on plate tectonics and also discovered the story of Morgan's lecture; sent a telegram to 'Nature' saying that I would like to hold this paper but it was too late; previously I'd asked Bill Menard at Scripps who knew a little of what I'd been working on and advised publication; at Lamont everybody was working on the oceans and I wondered whether it would work on continents too; knew one should look at very large areas contemporaneously so looked at earthquakes from the Azores to Eastern Iran; then went to Princeton where I found that in the previous year Morgan and I had solved two or three problems using identical mathematics in exactly the same way – plate tectonics was one, another was the thermal structure of the oceans and another was looking at earthquake mechanisms in a different way to seismologists; revelation to me that subjects get to a certain point and then its obvious; glad that I was born in 1942 as I would have missed this wonderful time if born later; I was in right at the beginning, published two of the first papers in it, had a research fellowship at King's, no attachment in the university, and could simply work flat out on the development; published papers on all aspects including one with Nick Jardine on the implications for the evolution of animals and plants

52:57:24 I came back to Cambridge in 1968 and lived in King's for six months; went on a cruise in the Indian Ocean with a friend from Scripps, John Sclater, and we found magnetic anomalies on the sea floor of the Indian Ocean which were formed when India moved northwards and collided with Tibetan Himalayas; decided between us to work out the whole geological history of the Indian Ocean and we got it right and wrote an enormous paper which occupied the whole issue of the 'Geophysical Journal of the Royal Astronomical Society'; later on this got us fellowships at the Royal Society; that was published in 1971 and up until then I had spent six months in Cambridge, six months in California; I had gone from being an unknown graduate student to someone who everybody in the field knew of in just two years – an extraordinary sensation; got a senior research fellowship for another four years and a University position, both in 1969; at same time was offered a full professorship at Manchester but I had no desire to be on my own and so visible; I wanted to get on with my research and I liked Cambridge; it was not a teaching department so I had no duties apart from a few graduate students; only problem was that I was about to get married and was rather poor; quite sure now that I made the right decision because of the intellectual attraction of this place; you do science with others not by yourself