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Duyurular
Duyurular

Mr President, Ladies and Gentlemen

I appear before you today to undertake a task that marks one of the happiest occasions of my entire life: to present to you Professor Kevin Burke as this year’s Penrose medallist, the highest honour the Geological Society of America can bestow on a geologist. Yet it is an impossible task at the same time, simply because neither the time allotted to us this evening, nor any other time span that may be allotted to such a task can possibly be sufficient to do justice to it. A very appropriate short-cut would have been to say  that Kevin Burke has massively furthered geology during his lifetime. If such a statement is made about most geologists, one would think that the person in question has contributed to one or more branches of the vast field of geology. In Kevin’s case, ‘furthering geology’ must be taken at its literal sense, implying furthering the entire earth sciences taken at one embrace, as, for example,  did sir Charles Lyell in his time, or Eduard Suess, for I am unable to think of any branch of geology, taken at its Lyellian breadth, that Kevin has not furthered.

Last time I looked at his vita, his published papers had neared 400 in number. They start with standard field descriptions in his PhD area in western Ireland and continue, till the mid-sixties, through his field papers concerning African tectonics while detailed by the British Geological Survey to the the British Atomic Energy Commission, papers on the Caribbean while he was busy founding the Geology Department in Kingston, Jamaica, and when he was in Ibadan Nigeria, where in 1966 he initiated the Benue Valley Project. Already in these early years one sees the inclination to diversify in problems tackled (from granite problems in Ireland to marine geology in Jamaica and to beryllium prospecting and the gases in the African lakes in the Great Rift Valley, in addition to the classical field descriptions, geomorphological problems ranging from processes of tropical erosion to pedology and gravity  studies) and a predilection to put forward explanations in the form of daring, but testable hypotheses. In those days this was not common among field geologists. Indeed, such projects as the Yallahs basin in Jamaica and the Benue Trough Project in Ibadan were generated because of Burke's interest in understanding the processes that underlay the objects he was studying.

When plate tectonics came about in the mid-sixties, Kevin was one of the readiest geologists to receive it. Already in 1970 we see him outlining what later came to be known as the Burke hypothesis (so named by the late Marshall Kay) of continental separation caused by plume-generated uplifts and the rift-rift-rift junctions forming atop them. His type examples were the Red Sea-Gulf of Aden and the Ethiopian Rift and the Benue Trough-Central Atlantic-South Atlantic. The Benue Trough could play such a significant place in the formulation of the Burke hypothesis owing to the data collected largely because of Kevin's initiatives in Ibadan. At the same time he conceived, with his life-long colleague and friend John F. Dewey,  another Penrose Medallist, the Pan-African orogeny to be an ancient analogue of the Himalayan/Tibetan area of wide orogeny and thermal basement reactivation. This was Burke's response to Kennedy's problem of having wide areas of thermal basement reactivation—much wider than could be accommodated in classical models of orogeny in pre-plate tectonic days and those inherited by plate tectonics. This is a nice example illustrating Burke's originality, broad knowledge of world geology, and quickness of mind. Both the Burke continental rifting model and the Himalayan/Tibetan model of wide orogeny were applied to problems elsewhere in now-classical papers he wrote with John Dewey in 1973 and 1974.

Also in the early seventies Burke worked together with Tuzo Wilson, the father of plate tectonics, and Bill Kidd, then a young assistant professor just out of university, on the problem of the fixity of mantle plumes. In a paper published in Nature, they showed, for the first time (antedating Peter Molnar's similar results), that mantle plumes are not stationary but that they move with respect to each other, albeit at rates considerably slower than plate motion rates. Burke also showed, in conjunction with Wilson, that the anomalous elevation of Africa (known since the hypsometric studies by Chavanne in 1881) was most likely due to its having been stationary with respect to the pattern of mantle convective circulation beneath it. This provided an elegant solution to the long-standing problem of the origin of African basin and swell structure (which Burke had learned as an undergraduate in London, from Holmes' famous text-book and later explained using the Thiessen polygon method with his student Richard Thiessen) and the concomitant magmatism, a group of processes that Erich Krenkel had called magmarsis in 1922. Magmarsis had remained mysterious and unintelligible until Burke tackled it and in the process made the entire post-Palaeogene tectonics of Africa intelligible. In 1996 he was invited to give the Du Toit lecture in South Africa where he summarised his view of the tectonics of the continent since 30 Ma ago.

In the early seventies we see also other studies by Kevin concerning Nigerian observations as applied to world-wide problems. For example his demonstration of the role of the earth worms (over that of termites) in the formation of laterites, field data on rare catastrophic erosion processes (rain heaving of boulders and the damage they do as they are rolled down slopes where they normally stand in a metastable condition), and the publication of a Bouger gravity map of Nigeria.

My path crossed Burke's in 1975. I had met him in Albany during a Christmas visit to the Deweys. He later came to Houston (where I was a student) with Bill Kidd for a NASA meeting. It was then that I told him that the Burke model of continental rifting did not work for the Rhine rift in western Europe. He listened carefully to my arguments. When I joined the Albany department in 1976, I ended up writing a paper with him on the Rhine rift, which was the source of our later paper on the passive versus active rifting distinction.

At about that time Burke became involved with the tectonics of the Archaean. He knew the Archaean from Africa and from Canada. He knew that the then current synclinal model of the greenstone belts did not do justice to the structural complexity the greenstone belts displayed. Together with Dewey and Kidd, he compared the greenstone belts tectonically with the present-day sutures lined by island arcs and accretionary complexes. I realised the depth of his insight when, years later, I myself visited the Yilgarn, Superior and the Issua greenstone belts. Kevin's contribution to our understanding of the Archaean tectonics has been probably greater than most people who devoted lifetimes to the Archaean. In the seventies Kevin also looked at the Proterozoic and recognised the old suture belts and adjoining belts of thermal reactivation in former Tibet-type plateaux. This was, and remains, the best interpretation of many areas of previously enigmatic, so-called anorogenic granite magmatism. His paper with Dewey and Kidd on the distribution of sutures in the world was the first attempt to show the operation of plate tectonics through time on a truly world-wide basis. It was a Penrose conference that he organised in 1977 with peter Molnar that initiated the modern phase of geological research on Tibet on an international basis.

In the late seventies Burke organised a project to map the sutures and rifts of the world for NASA to form a basis for satellite geophysical data interpretation. The AGTG (Albany Global Tectonics Group) reports that resulted from that project have been the basis of many a later regional study by many groups who received the reports from NASA. Alsa an offshoot of the same was the contribution by the Albany group (headed by Kevin) to the tectonic aspects of the Basaltic Volcanism Project.

In the beginning of the eighties Burke turned his attention again to the Caribbean and together with his students undertook detailed field studies of the northern, southern and southwestern parts of the plate and its active frame. This was in part triggered by his realisation that the Caribbean oceanic crust was anomalous and represented a plateau that came from the Pacific and trapped in its present position. This hypothesis was corroborated but brought with it numerous implications for the tectonics of the frame of the Caribbean. Among numerous one, an offshoot was his study of the nature and timing of the closure of the Panama isthmus and the influence of that closure to the world climate.

With world climate considerations Burke began concentrating on global events and published with me (the idea came from him) a paper on the influence of the sudden flooding of the South Atlantic basin in the Aptian on the world-wide sea-level. He showed that the estimates of the Vail group in Exxon for the Aptian regression were far too large (60 metres versus 10 metres).

In the eighties he headed the Lunar Science Institute of Houston, which he quickly turned into a meeting place of diverse talents from diverse parts of the world. His studies, among others, on the tectonics of Venus (Ishtar as a compressional plateau) and the Quaternary drainage history of the Sahara and the documentation of the palaeo-course of the Nile system belong to this episode.

In the nineties, Burke returned to rift problems and began taking Africa apart in some detail. He hopes to publish a book on the geology of Africa (as far as I know, nobody is better qualified for the job) and his Du Toit lecture in 1996 is the first fruit of this concentrated effort. He also documented the detailed tectonics of the great Amazon rift and showed its tectonic ecology in the framework of the late Proterozoic-early Palaeozoic tectonics of Gondwana-Land.

Ladies and gentlemen: tryying to list Kevin’s contributions is impossible; impossible even if one keeps only to the general topics he tackled during his lifetime. This is so not only because the numbers prevent us from doing so, but also because of the ways Kevin contributed to science: in addition to his published books, papers and abstracts, he has been always a great debater in meetings and an enthusiastic conversationalist. In his numerous conversations he has generously given ideas and data to many a future author. His memory is unequalled, his knowledge of world regional geology truly staggering. I have not yet met a geologist anywhere more knowledgeable than Kevin Burke in the entire sweep of the earth sciences, i.e., geology in the old, Lyellian, that is to say, proper sense. incredible quickness of mind, the speed with which he can review and bring to bear upon whatever may be at hand, the relevant information, are a wonder to watch.

I have been Kevin's student in Albany for six and-a-half years, during which I have come to know him and his family closely. I have admired Kevin Burke as a great teacher (not only in geology, but also in literature, music, history, philosophy, geography and many subjects pertaining to general culture). The atmosphere he and John Dewey created in Albany was the best academic and research atmosphere I have ever breathed anywhere in the world. I have learned from Kevin how to write papers, how to review papers, how to find information about diverse topics, regions, past research achievements in geology. His generosity with his time, his books, papers and his boundless knowledge belongs to the most cherished of my memories. Being with Kevin was like being at a rich and delicious fountain of knowledge from which one could continuously drink.

The most valuable thing I learned from him was how to think in and about science. His boldness in generating hypotheses and his mercilessness and unbending honesty in testing them, including his own most cherished views, may perhaps best be compared with the similar attitude of Sir Charles Lyell. His curiosity is without limits and highly contagious. Being a student in the vicinity of Kevin must be the best preparation any research student can hope to have.

He and his family (together with the Dewey family) essentially made my life in Albany possible. Their homes were always open to their students. Amidst a very heavy research and teaching schedule, Kevin (who was also the department chairman) was always ready to listen to any student who wished to talk to him any time. He always appeared as if he had all the time in the world to listen to him or her and consequently made the student feel comfortable. He and Dewey set lofty examples with their affectionate family lives to their students. One has always felt the warmth of human affection pervading their lives and it is a feeling that I have cherished as a foreign student. To this day I remain deeply nostalgic about my days in Albany. Kevin had a huge share in creating that unforgettable place, now referred to among us, the Albany students of those remarkable days, as the 'Camelot.' That department is no more, possibly appropriately so. I cannot imagine any leader today being able to do justice to its  glorious past. It was a unique achievement, somewhat like Eduard Suess’ school of Viennese giants in the last quarter of the nineteenth century, administered by Kevin’s genius as a science administrator, so little talked about, because it is so massively overshadowed by his original contributions as a researcher.

It is impossible for me to write about Kevin without feeling very emotional. I do not have the intellectual capacity to judge him as a geologist or as an intellectual. He towers far too high above me in brains and in knowledge. Without him, it would have been impossible for me to obtain what modest success I may have obtained, or to be able to taste the immense joy I have had in pursuing geology. He was my teacher and has remained my teacher ever since. His friendship is one of the most cherished attainments of my life.

I have been both a student of geology and its history. I have closely studied the lives of many great geologists. Three of them remind me of Kevin most by their character and accomplishments and their love for, what Kevin calls, 'our beloved planet': Alexander von Humboldt, Sir Charles Lyell and Eduard Suess. Giving Kevin the Penrose Medal honours not only for Kevin Burke, but also the Geological Society of America and will add further luster to its already illustrious annals. That this honour comes to Kevin (and to the Soceity) at this late stage in Kevin’s career is I think the best testimony to his being so farther ahead than most and to his sincere modesty (masked for many by his ebulliant enthusiasm at times wrongly interpreted as arrogance). But that it did come reflects on us all as members of the international geological community comprehended under the illustrious umbrella of the GSA and we  all bask in the glory that Kevin Burke has added to the attainments of our wonderful science.

Mr President, Ladies and Gentlemen, I consider it as one of the most momentous instances in my life to present to you our this year’s Penrose medallist, Professor Kevin Charles Antony  Burke, geologist.