ALFRED WEGNER
Alfred Wegner, a glaciologist and a climatologist first advocated that the continents (although Isacc Newton is really credited with a suggestion to this effect based on his observations on variation of gravitational constant) were first grouped in a single landmass called Pangaea which split up to give rise to present day continents and oceans. His thesis was first based on the matching coast lines either side of the Atlantic ocean but later he also showed geological and palaeontological similarities on either side. His book die erstehung der kontinente und ozeana in German was first translated into English in 1928 and A L du
Toit, a South African geologist considerably developed on this and suggested an orogenic belt called SAMFRAU across the Gondwanaland. Wegener died in Greenland on his third expedition in 1930, covered by an avalanche. His theory forms the base on which the theory of sea floor spreading and plate tectonics was later developed principally from geochronologic and palaeomagnetic
evidence Perhaps Alfred Wegener's greatest contribution to the
scientific world was his ability to weave seemingly dissimilar, unrelated
facts into a theory, which was remarkably visionary for the time. Wagener
was one of the first to realize that an understanding of how the Earth
works required input and knowledge from all the earth sciences.
.Wegener's scientific vision sharpened in 1914 as he was recuperating in a
military hospital from an injury suffered as a German soldier during World
War I. While bed-ridden, he had ample time to develop an idea that had
intrigued him for years. Like others before him, Wegener had been struck
by the remarkable fit of the coastlines of South America and Africa. But,
unlike the others, to support his theory Wegener sought out many other
lines of geologic and paleontologic evidence that these two continents
were once joined. During his long convalescence, Wegener was able to fully
develop his ideas into the Theory of Continental Drift, detailed in
a book titled Die Entstehung der Kontinente und Ozeane (in German, The
Origin of Continents and Oceans) published in 1915.
Wegener obtained his doctorate in planetary astronomy in 1905 but soon
became interested in meteorology; during his lifetime, he participated in
several meteorologic expeditions to Greenland. Tenacious by nature,
Wegener spent much of his adult life vigorously defending his theory of continental
drift, which was severely attacked from the start and never gained
acceptance in his lifetime. Despite overwhelming criticism from most
leading geologists, who regarded him as a mere meteorologist and outsider
meddling in their field, Wegener did not back down but worked even harder
to strengthen his theory. A couple of years before his death, Wegener finally achieved one of his
lifetime goals: an academic position. After a long but unsuccessful search for a
university position in his native Germany, he accepted a professorship at the
University of Graz in Austria. Wegener's frustration and long delay in gaining a
university post perhaps stemmed from his broad scientific interests. As noted by
Johannes Georgi, Wegener's longtime friend and colleague, "One heard time
and again that he had been turned down for a certain chair because he was
interested also, and perhaps to a greater degree, in matters that lay outside
its terms of reference -- as if such a man would not have been worthy of any
chair in the wide realm of world science."
Ironically, shortly after achieving his academic goal, Wegener died on a
meteorologic expedition to Greenland. Georgi had asked Wegener to coordinate an
expedition to establish a winter weather station to study the jet stream (storm
track) in the upper atmosphere. Wegener reluctantly agreed. After many delays
due to severe weather, Wegener and 14 others set out for the winter station in
September of 1930 with 15 sledges and 4,000 pounds of supplies. The extreme cold
turned back all but one of the 13 Greenlanders, but Wegener was determined to
push on to the station, where he knew the supplies were desperately needed by
Georgi and the other researchers. Travelling under frigid conditions, with
temperatures as low as minus 54 °C, Wegener reached the station five
weeks later. Wanting to return home as soon as possible, he insisted upon
starting back to the base camp the very next morning. But he never made it; his
body was found the next summer
Wegener was still an energetic, brilliant researcher when he died at the age
of 50. A year before his untimely death, the fourth revised edition (1929) of
his classic book was published; in this edition, he had already made the
significant observation that shallower oceans were geologically younger. Had he
not died in 1930, Wegener doubtless would have pounced upon the new Atlantic
bathymetric data just acquired by the German research vessel Meteor in
the late 1920s. These data showed the existence of a central valley along much
of the crest of the Mid-Atlantic Ridge. Given his fertile mind, Wegener just
possibly might have recognized the shallow Mid-Atlantic Ridge as a geologically
young feature resulting from thermal expansion, and the central valley as a rift
valley resulting from stretching of the oceanic crust. From stretched, young
crust in the middle of the ocean to seafloor spreading and plate tectonics would
have been short mental leaps for a big thinker like Wegener. This conjectural
scenario by Dr. Peter R. Vogt (U.S. Naval Research Laboratory, Washington,
D.C.), an acknowledged expert on plate tectonics, implies that "Wegener
probably would have been part of the plate-tectonics revolution, if not
the actual instigator, had he lived longer." In any case, many of Wegener's
ideas clearly served as the catalyst and framework for the development of the
theory of plate tectonics three decades later.
Some account credited to USGS site
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