The Renaissance of Continental Drift

The Renaissance of Continental DriftThe Renaissance of Continental Drift – an original piece by Alan Mason

The one hundredth anniversary of the publication of Alfred Wegener’s Theory of Continental Drift was recently marked on deskarati by the posting of a festschrift (tribute) to the man. I have long admired Wegener and became convinced of the correctness of his theory long before it became the orthodoxy that it is today.

Wegener was, I believe, very shabbily treated by the geological/geographical establishment of the twentieth century who never really gave his work the serious attention it deserved. The man should have been honoured with a Nobel Prize for one of the great scientific theories of the century. Ask yourself, “How many scientific theories published a hundred years ago get a mention nowadays practically every week in a variety of publications from children’s books to scientific journals?” The answer is almost none, with the exception of Wegener’s Theory of Continental Drift.

1. The new island of Surtsey, off Iceland, was created in 1963-67 by undersea volcanic eruptions due to upwelling magma below the Mid-Atlantic Ridge

In a comment on the original deskarati posting, I claimed that his theory had undergone something of a renaissance in the 1950s. Penguin Books produced a series of pocket-sized quarterly scientific reviews entitled “New Biology” during the 1950s and 1960s. The articles were authoritative as they were written by working scientists in the field.

Number 29 published in 1959 contained an article by a palaeobotanist, W G Chaloner, of University College, London, entitled, “Continental Drift”. I have not included any of the text or its illustrations, which are now rather old-fashioned, but several of Chaloner’s arguments are advanced here.

1. THE SAMFRAU GEOSYNCLINE

The name SAMFRAU is derived from the continents – (S)outh AM)erica, A(FR)ica, and (AU)stralia, as these are the regions in which this particular geosyncline has been observed. A syncline is a U-shaped distortion of what were originally horizontal strata.

 2. The formation of a syncline

A geosyncline is a major structural feature of a continental surface, often an elongated basin which becomes gradually filled with more and more sediments. The weight of these sediments causes the progressive subsidence of the basin floor.

The SAMFRAU geosyncline is a characteristic geological feature which today is found scattered about different parts of the southern continents. Figure 3 shows the SAMFRAU geosyncline on the modern world map and a comparison with the Palaeozoic period when the southern continents were close together and the geosyncline was more or less continuous.

3. The SAMFRAU GEOSYNCLINE on a modern world map (top) and (lower) on a Palaeozoic assembly of the world’s continents.

 2. GLACIATION IN LATE CARBONIFEROUS TO EARLY PERMIAN PERIODS

Geologists have uncovered evidence of a major Ice Age at the end of the Carboniferous Period and the beginning of the Permian Period about 300 million year ago. If the resultant ice sheet was superimposed on the modern map of the continents it would have locked up most of the water on the planet. (4)

If, however, we assumed the southern continents were much closer together, then this southern ice sheet would have been much the size of the northern ice sheet of the recent ice age about one million years ago. The picture from assumed continental drift is altogether more believable.

 4. Carbo-Permian Glaciation shown on modern (top) and ancient (lower) world maps.

3. DISTRIBUTION OF SOME KEY FOSSILS

Glossopteris was an ancient fern. (Pronounced glosso terris as the Greek p is silent) Its fossils are widely distributed in the southern continents, including Antarctica, along with a range of other plant fossils typical of the period. These are now called “the Glossopteris flora” and they define a particular habitat of the Permian period 300 million years ago.

Figure 5 shows a photograph of a Glossopteris fossil which has been graphically processed so that it appears green as in life. Ferns reproduce by microscopic spores which are spread by the wind. The spores are produced in brown-coloured sporangia, also shown in the enhanced illustration.

5. Two fossils from the Permian period 300 million years ago

The mesosaurs (meaning “middle reptiles”) are ancestors of the later dinosaurs and they are known from fossils in two widely separated regions, central South America, and West Africa. A reconstruction of the type genus, Mesosaurus, is shown in Figure 5.

The modern world map shows the rather puzzling distributions of the two fossils. (6) Glossopteris is seen to have a world-wide distribution but only in the southern tips of the southern continents. How could this be? Was it once found over the whole world, even though there is no evidence for this? How else can we explain the isolated populations in India and the tip of Africa, as well as the completely separate continents of Antarctica and Australia?

When the southern continents are grouped together, as in Wegener’s theory, shown in the lower illustration of Figure 6 all becomes clear. Glossopteris had a wide, single, and continuous distribution in the Permian. It was probably a tropical fern and only flourished in the warmest regions.

In Permian days Antarctica was thousands of miles from the South Pole, and only moved southwards during the next 300 million years. The gradual exploration of Antarctica in the last 60 years has amply confirmed its previous geological history in more northerly and warmer regions.

The modern distribution of mesosaur fossils is even more of a puzzle than that of Glossopteris. How could we have identical sets of fossils from two regions widely separated by thousands of miles of open ocean? The mesosaurs were not aquatic reptiles. When we look at the lower map in Figure 6, all becomes clear. The mesosaurs had a central, but limited single distribution, in a geographically distinct region. What is now South America, and West Africa, gradually broke apart at the Mid Atlantic Ridge. By then the mesosaurs, having given rise to a range of dinosaur ancestors, had become extinct leaving only their fossils behind to puzzle future generations.

6. Modern and Permian Distributions of Glossopteris and Mesosaur Fossils

THE WORK OF ALFRED WEGENER

Wegener presented his ideas to the German Geological Association in Frankfurt on 6 January 1912. It was not well received and neither was the repeat lecture in Marburg four days later. The geologists of the time simply could not believe that the continents were capable of breaking apart, or that they could drift on their underlying base.

One of the few German geologists to support him was Wladimir Koppen who became a lifelong advocate of Wegener’s theory. Koppen advised that promoting such a revolutionary idea could harm Wegener’s academic career, and this proved to be the case.

Later that year Wegener joined an expedition to Greenland to make meteorological and geological observations. He wintered with the party on the Greenland ice-cap. (7) On returning to Germany in the spring of 1913 he married Koppen’s daughter, Else. Within a year he was called up to serve as an infantry officer on the outbreak of war in August 1914.

 7. Alfred Wegener In His Younger Days

Despite his military appearance, (7) Wegener hated war. He was wounded in the arm and the neck and fortunately was eventually transferred from the front to the Army’s new meteorological service. This enabled him to pursue his scientific studies and he produced a book in 1915 which expounded his ideas in more detail.

The British Royal Geographical Society considered Wegener’s theory in 1923. Though admitting that it explained much the group as a whole rejected it. One speaker said that no one who “valued his reputation for scientific sanity” could support such a theory. He was correct; the strength of scientific conservatism was very strong. He was more violently criticised for “not seeking the truth, but advocating a cause, and is blind to every fact that tells against it.” (Philip Lake)

In America the response was much the same. The President of the American Philosophical Society called the idea of continental drift, “utter, damned rot!” All this affected Wegener’s professional progress and he remained a lecturer, unable to obtain a professorship in a German university. He left Germany for Austria in 1924, and a professorship was created for him by the sympathetic University of Graz.

In 1928 Wegener attended a symposium in New York where his theory was roundly attacked by a succession of experts, who frequently treated him with scorn and discourtesy. He remained largely silent, realising years ago that this kind of meeting was simply a circus, and few were prepared to listen dispassionately or examine the actual evidence.

Apart from Wladimir Koppen in Germany, Wegener had geological allies in Émile Argand in Switzerland, and Alexander Du Toit in South Africa.

8. Greenland Pony Hauling Sledges of Supplies For Wegener’s 1930 Expedition

In 1930 Wegener led another expedition to Greenland. There were supply problems for the most isolated of the outposts and Wegener had to lead a rescue expedition. He was successful in the attempt but on the return journey to the base camp with a local Greenlander, Wegener died, probably of a heart attack. He was 50 and had celebrated his birthday only a few days beforehand.

His companion had buried him in the snow, and had carefully marked the spot with skiis and ski poles for the later search parties. The Greenlander, Vullemsen disappeared after burying Wegener and was never seen again. The rescue parties, having discovered Wegener’s body, re-interred it and erected a cairn of snow blocks over the site. This is still Alfred Wegener’s last resting place.

As Russell Miller concludes, “the obituaries were laudatory and filled with lavish praise of Wegener’s achievements,” but there was little mention of continental drift, “which by then was generally considered to be nothing more than a bizarre fantasy – an aberration in an otherwise exemplary life.” (p. 59, Miller, op.cit.)

Had Wegener survived into his eighties he might have had the satisfaction of seeing his theories finally vindicated.

REFERENCES

As stated earlier, the principal source for the ideas in this short article was “Continental Drift”, by W G Chaloner, in Volume 29 of “New Biology”, Penguin Books, 1959. Further information on Alfred Wegener came from “Continents in Collision” by Russell Miller, Time-Life Books, 1983.

ILLUSTRATIONS

1. The new island of Surtsey, off Iceland, created in 1963-67, (Miller, op.cit.)

2. The formation of a syncline (Author)

3. The SAMFRAU Geosyncline (Author)

4. Carbo-Permian Glaciation (Author)

5. Two fossils from the Permian period (Mesosaur, Miller, op.cit. and Glossopteris after Chaloner, op.cit.)

6. Modern and Permian Distributions of Glossopteris and Mesosaur Fossils (Author)

7. Alfred Wegener In His Younger Days (Miller, op.cit.)

8. Greenland Pony Hauling Sledges of Supplies (Miller, op.cit.)

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One Response to The Renaissance of Continental Drift

  1. Deskarati says:

    A very enlightening piece Alfy. I particularly enjoyed the works and life of Alfred Wegener

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