Exploration Insights Great Geos ebook | Page 86

86 | Great Geologists that were strongly suggestive of a supercontinent assembly were dismissed for the want of a theory to explain them. Not all eminent geologists of the time were opposed to Wegener’s ideas. The South African Alexander du Toit published a comprehensive favourable comparison of South American and African geology in 1927 and published Our Wandering Continents in 1937. The British geologist Arthur Holmes provided an illustration of how convention currents in the mantle could drive continental movement in 1929, an argument that Wegener himself had advanced in later editions of his “Origins…” book. To quote Holmes “granted convection currents the continents may open out and reclose in an endless pattern of varieties.” Nonetheless many of the leading geologists of the time, especially Americans such as Charles Schuchert, Edward Berry (an article entitled “Germanic Pseudo-Science” gives a flavour of his sentiments) and Bailey Willis, were “united in a crusade against mobilism” and remained staunchly against continental drift for the entirety of their careers. It would take the 1960’s development of plate tectonic theory drawn from oceanographic and paleomagnetic observations to convince geologists that Wegener had been right in his hypothesis that the continents were not fixed. Wegener died not long after his 50th birthday in 1930 when participating in his fourth Greenland expedition. After delivering supplies by dog-sled to the Eismitte research station near the centre of the Greenland ice sheet, he suffered an apparent heart attack on the return journey on skis to the west coast. His body was buried by his Inuit companion (who himself perished soon after) and discovered the following year. At the request of his widow, his grave remains on Greenland, the location of some of his most important meteorological research. What is striking about Wegener’s geological work is the holistic approach he took. For him, “the forces which displace continents are the same as those which produce great fold- mountain ranges. Continental drift, faults and compressions, earthquakes, volcanicity, transgression cycles and polar wandering are undoubtedly connected causally on a grand scale.” No geologist today would argue with the sentiment of this conclusion. We owe a great debt to Alfred Wegener for directing geological thought to this bigger picture. REFERENCES This essay has drawn upon information from the following sources: Frankel, H.R. 2012. The Continental Drift Controversy. Volume I: Wegener and the Early Debate. Cambridge University Press. 604pp. Gohau, G. 1990. A History of Geology. Rutgers University Press. 259pp. Greene, M.T. 1982. Geology in the Nineteenth Century. Cornell University Press. 324pp. Greene, M.T. 2015. Alfred Wegener. John Hopkins University Press. 675pp. Hallam, A. 1973. A Revolution in the Earth Sciences. Clarendon Press, Oxford. 127pp. Hallam, A. 1983. Great Geological Controversies. Oxford University Press, 244pp. Lawrence, D.M. 2002. Upheaval from the Abyss. Rutgers University Press, 284pp. Le Grand, H.E. 1988. Drifting Continents and Shifting Theories. Cambridge University Press. 313pp. Molnar, P. 2015. Plate Tectonics: A Very Short Introduction. Oxford University Press, 136pp. Oldroyd, D.R. 1996. Thinking About the Earth. The Athlone Press, 410pp. Oreskes, N. 1999. The Rejection of Continental Drift. Oxford University Press. 420pp. Powell, J.L. 2015. Four Revolutions in the Earth Sciences. Columbia University Press, 367pp.