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I agree that there has been a tendency to rewrite Wegener's history as a rejected loner. Being schooled in geology in the 1960s in southern Africa, we were taught continental drift as virtually proven because the geological evidence was so strong that the geophysicists would have to find a way to make the process work---which they eventually did with dazzling effectiveness for the theory of plate tectonics. Continental drift was an accepted idea in southern Africa largely due to the efforts of Alexander du Toit, the greatest geologist produced by South Africa. His two books, "A Geological Comparison of South America with South Africa" (1927) and "Our Wandering Continents" (1937) supplied overwhelming geological support to Wegener's brilliantly creative speculations and coined the supercontinent terms Laurasia and Gondwanaland. Our impression as students in the 1960s was that the hypothesis of continental drift was sympathetically received throughout Gondwana and by British geologists acquainted with Gondwana geology because of historical ties. Martin Jackson -----Original Message----- From: Tectonics & structural geology discussion list [mailto:[log in to unmask]] On Behalf Of Krueger, Scot Sent: Thursday, October 25, 2012 1:29 PM To: [log in to unmask] Subject: Re: alfred wegener It seems to me that the legacy of Wegener, and particularly the notion that his theory was not widely accepted until the early 1960's, contains a fair bit of revisionist history. I will admit up front that my grandparents were not even born yet when Wegener first published Origin of Continents, and I did not become a professional geologist until well after plate tectonics was firmly established, but I have had many conversations with senior geologists from the generations before mine and they all feel that the theory was widely recognized as having potential to explain a good many geological phenomena, but that there were still serious unresolved scientific issues. The biggest drawback came from wegener's own rhetorical flourishes of describing continents as sailing through the mantle like boats. The physics of the day was well enough established to show that it was mechanically impossible for something as relatively squishy and deformable as quartzofeldspathic crust to rigidly plow through much more durable olivine-pyroxene mantle. That physics still holds today. The continents do not drift with respect to their immediately underlying mantle. It was only the wartime efforts to better understand the oceans that led to the discoveries of things like ridges and fracture zones and oceanic magnetic stripes that finally forced the scientific community to realize that the flaw was not in the concept of continents moving with respect to each other, but with the fixist view of the mantle. We now know that the mantle convects and the continents largely go along for the ride. The opposition to continents drifting through the mantle was sound. It was only when the evidence for shifting surface plates became irrefutable that the light came on and numerous people realized it was the mantle that was moving. It was this new synthesis, where the mantle moves and the continents go along for the ride, that allowed the plate tectonic theory to become nearly universally accepted as the dominant paradigm for understanding the large scale behavior of the Earth's surface. The revisionist history comes from the folks who suggest that Wegener's theory was essentially ignored for decades and was nearly forgotten by the 1950's. From the discussions I have had it does not seem that this was what happened. The handful of people I have talked to who went through university in the 40's and 50's were all taught Wegener's theory. They all felt it had potential to alter our view of the Earth and explain many geological paradoxes. But they were also taught the reason's why the theory, as postulated, did not fit with a lot of our clear understanding of the physics of rocks. Arthur Holmes ended his 1944 book, Principles of Physical Geology, with a chapter on continental drift. I've heard that continental drift was very popular in Australia in the 1950's. but with an expanding Earth spin which has since been discarded. My father, who attended the geology department at the University of Minnesota in the early to mid 1950's, recalls that his teachers taught Wegener and continental drift in a very positive light. The geological evidence from common stratigraphy and faunas across oceans was fairly compelling to most geologists, as it had been to geologists like Lyell and Wallace as far back as the mid 1800's. Much of the opposition came from the geophysical community, who were more in tune with concepts of rock strength and rheology. Once continental drift was recast as plate tectonics, where the mantle was moving rather than just the continents, the opposition melted away and the prevailing paradigm was born. I would love to hear any opinions on the matter from anyone else who has had discussions with the earlier generations who came into the field in the 30's to 50's to see whether they have heard similar stories. I wonder if the degree of acceptance or dismissal was different in different parts of the world. Scot Krueger -----Original Message----- From: Tectonics & structural geology discussion list [mailto:[log in to unmask]] On Behalf Of Van Staal, Cees Sent: Thursday, October 25, 2012 11:29 AM To: [log in to unmask] Subject: Re: alfred wegener On this topic, there is a brilliant paper in press in Geoscience Canada written by Paul Hoffman concerning Wegener's scientific career and the intricacies of the response of his peers to his continental drift theory. The paper is 5MB and hence can not be appended to this message, but for those interested I could send you the PDF separately. I append the last paragraphs of Hoffman's paper, which I think are very telling. " The noted American historian Mott T. Greene pointed out that neither Wegener's opponents nor his supporters, "seemed to have a clear grasp of a theory which comes having read it carefully" (Greene 1984). He suggests that, "the reason for this is a kind of guilty secret: most scientists read as little as they can get away with anyway, and they do not like new theories in particular. New theories are hard work, and they are dangerous-it is dangerous to support them (might be wrong) and dangerous to oppose them (might be right)." He concludes that, "most scientists wait until someone they trust, admire, or fear supports or opposes the theory. They can get two for one-they can come out for or against without having to actually read it, and can do so in a crowd either way." There is a good deal of truth in this, but a case could be made that Wegener's opponents tended to read him too closely, fixating on problematic details while missing the merits of the big picture. Finally, some say that Wegener was a loner, who had no students and founded no school of followers. Yet, Wegener's colleagues consistently describe how unaffected Wegener was by fame, how students were attracted by his openness, humility and clarity of expression (Benndorf 1931; Wegener 1939; Georgi 1962). Wegener had students and followers; they followed him to Greenland, not continental drift. I yield the last word to Sir Edward Bailey, writing (coincidentally) on the 50th anniversary of Wegener's The Origin of Continents (Bailey 1962), the nadir of his theory's prospects, and a decade before the plate tectonic revolution: "From the human point of view there are two features of the Wegener hypothesis that arouse my continual wonder. The first is that Wegener stumbled on what may yet prove to be the greatest geological discovery of all time before he himself had begun to study geology. The second, that, after he had ransacked the literature and marshalled a hitherto meaningless wealth of apparent corroboration, he is treated by most geologists and physicists as a mere purveyor of nonsense." Cees van Staal Dr. Cees van Staal, senior scientist Geological Survey of Canada / Commission Géologique du Canada Natural Resources Canada / Ressources Naturelles Canada Government of Canada / Gouvernement du Canada 625 Robson Street / 625 rue Robson Vancouver, BC, V6B 5J3 Canada 604-666-2997 fax/télécopieur 604-666-1124 [log in to unmask] -----Original Message----- From: Tectonics & structural geology discussion list [mailto:[log in to unmask]] On Behalf Of Stuewe, Kurt ([log in to unmask]) Sent: October 24, 2012 08:48 To: [log in to unmask] Subject: alfred wegener As most of you will know, 2012 is the 100st anniversary of the 1912 publications of Alfred Wegener on continental drift that are often hailed as the discovery of plate tectonics. Alfred Wegener later became a Professor at Graz University (until his death in 1930) and we are therefore organizing a small symposium in honor of his discovery on November 9th at Graz University. Should any of you be near enough so that the interest in the event outweighs the burden of travel, then we very much welcome you to the event ! I attach an invitation. Kurt Stüwe ------------------------------------------ Ao Prof. Dr. Kurt Stuewe Institut fuer Erdwissenschaften Universitaetsplatz 2 A-8010 Graz AUSTRIA http://wegener.uni-graz.at http://www.alpengeologie.org --------------------------------------------