Mantle Plumes May Be Real (or maybe not)

Tuzo Wilson, explaining Earth's plumbing.

Tuzo Wilson, explaining Earth’s plumbing.

Godess making mountains.

The goddess Pele, dreaming of plumes.

Geophysicist Tuzo Wilson had a creepy daydream. He imagined himself lying at the bottom of a creek, looking up at water flowing overhead. He blew bubbles. They rose, were caught by the current, and drifted away. He came back from his mini-nightmare with an idea about the way the Hawaiian islands formed. Bubbles of magma rose from deep within the Earth, broke through the crust, and drifted along because of plate tectonics.

The original Hawaiian settlers had a similar idea. They knew that the weathered northwest islands were much older than the new big island they called Hawaii. They believed that the fiery goddess Pele had successively emerged from the underworld, creating a series of volcanic islands over the ages.

Wilson was 55 at the time that his imagination discovered a way to explain the Hawaii island chain. His first attempt to publish “A Possible Origin of the Hawaiian Islands” failed when the scientists reviewing it at a leading American geophysical journal found the idea too radical. They rejected it. Tuzo scrambled to the Canadian Journal of Physics, which published his paper in 1963 – probably because they didn’t realize it was such a controversial subject, Tuzo figured.

Tuzo Wilson’s paper explained that the Hawaiian islands formed in a string because the Pacific tectonic plate slowly slid across a fixed hotspot while a plume of magma rose directly from deep below.   This was an important idea because plate tectonics – new at the time – was struggling to explain anomalous volcanic activity occurring in places like Hawaii, thousands of kilometres from the rubbing and colliding spots where crustal plates met.

Hawaiian beachSome geophysicists don’t believe in plumes. They suggested that the material creating island paradises is sourced just below the lithosphere. The jury is out; however, most who have studied it for the past fifty years have cautiously agreed with Wilson’s original thesis. Similar streams of hot mantle rising in hot ribbons of rock possibly cause thermal events in Réunion, Yellowstone, Iceland, Galápagos, Tahiti and at least forty other places scattered about the globe. With his near-mystic vision, Tuzo Wilson invented a whole new way to understand what’s causing some of the Earth’s volcanic activity.

But not so fast.  Ten years after Wilson, in 1972, the father and son geology team of Howard and Arthur Meyerhoff took an awkward stand against all forms of plate tectonics and against Tuzo Wilson’s plume theory. They generated vigorous pleas alerting fellow earth scientists to the pitfalls of those new ideas.

Arthur Meyerhoff (1928-1994)

Arthur Meyerhoff (1928-1994)

The Meyerhoffs assembled obscure facts that disputed tectonic motion. They released reasonable commentaries voicing their opposition to the nascent theory. They were usually correct in pointing out weak and contradictory aspects of plate tectonics. They asserted their opposition was based on “geological fact, which nothing can change.”  Almost invariably, however, a scientist who clutches facts that “nothing can change,” is proven wrong. The ‘facts’ often change due to new data, investigation, and confirmation. The Meyerhoffs protested mobile continents, but didn’t provide an alternative that explained earth history as convincingly as plumes and plate tectonics.

In time, the younger Meyerhoff, Arthur,  realized that the role of naysayer wasn’t enough. He needed to add something positive to the discussion. In 1988, he proposed a creative alternative earth-model: an interconnected near-surface world-wide plumbing system that conveyed melted igneous rocks. This relatively shallow plumbing system, he suggested, was being misinterpreted as plate tectonics. He carefully explained it in his posthumously published 1996 book, Surge Tectonics, which became  popular among followers of his surge theory. And, in fact, there has been some evidence to support the notion that sub-crustal flows supply the Hawaiian island chain. In 2011, Qin Cao and her team at M.I.T. seemed to have found a hot pool of magma in the shallow mantle that could be sourcing the growth of the Hawaiian islands – possibly in a non-plume-like manner.

But plumes still has advocates. And more data has changed the idea yet again. Seismic tomography has helped by monitoring earthquake energy waves as they vibrate through the mantle. Receivers record arrivals of the earthquake signals at thousands of surface locations. Variations in those arrivals indicate waves have been influenced by variations in composition, phase, density, pressure, or temperature of mantle rock. Seismic waves travel more slowly through hotter rock. If those changes could be accurately mapped, shallow pipes and plumes might be spotted – if they exist.

Example of seismic tomography. (Source: NASA)

Example of seismic tomography   (Source: NASA)

Using seismic tomography, it should have been straight-forward to map pipes or channels or deep plumes surging with hot streams of mantle. But for over 50 years, we didn’t have an unequivocally clear rendering of a narrow, ribbon-like plume. The idea that hot spots exist became, to some scientists, a kind of belief system. Belief in an invisible God-like force that explained some otherwise inexplicable phenomenon of nature.

daniel and carlA newer technique – telescopic seismic tomography, a focused sort of tomography – recently emerged and has been enlisted in the search for plumes. Arrays of surface receivers collect billions of bits of earthquake data, collate them, and then invert the waves, mapping their probable travel paths. Yet this technique is painfully tedious and can be error-prone. The energy waves arrive steeply dipping; the Earth’s innards are far from uniform; and, a delayed arrival may be due to any combination of composition, density, pressure, phase and/or temperature differences along the seismic wave’s travel path. This underlies a fundamental problem with geophysics: almost any observation can be due to a variety of causes. Nearly every geophysics problem has multiple non-unique solutions.

Thus, for over fifty years, plumes eluded researchers. Until now, perhaps.  With repeated studies and massive data-crunching, wide plumes of low velocity mantle material have finally been discerned. Last fall an important paper was released. It makes the strong and well-supported claim that plumes are real, putting plume atheists on the spot.

RomanowiczBarbara Romanowicz and Scott French published their findings in Nature in September. Broad Plumes Rooted At The Base Of The Earth’s Mantle Beneath Major Hotspots resulted from analysis of whole-mantle earthquake tomographic seismic data. Romanowicz’s group used full-waveform seismic computation in a  process that analyzed  energy waves from 273 large earthquakes and took 3 million hours of computation on a supercomputer.  The data indicate that plumes are real, but are much wider than the innocent trail of creek bubbles envisioned long ago by Tuzo Wilson. From the Nature paper’s abstract:

“We describe the use of a whole-mantle seismic imaging technique— combining accurate wavefield computations with information contained in whole seismic waveforms—that reveals the presence of broad (not thin), quasi-vertical conduits beneath many prominent hotspots. These conduits extend from the core–mantle boundary to about 1,000 kilometres below Earth’s surface, where some are deflected horizontally, as though entrained into more vigorous upper-mantle circulation. At the base of the mantle, these conduits are rooted in patches of greatly reduced shear velocity that, in the case of Hawaii, Iceland and Samoa, correspond to the locations of known large ultralow-velocity zones. This correspondence clearly establishes a continuous connection between such zones and mantle plumes. We also show that the imaged conduits are robustly broader than classical thermal plume tails, suggesting that they are long-lived, and may have a thermochemical origin.”

Are we done? Probably not. This was the state of the art in September, 2015. The conclusion is that plumes are real, are much broader than hypothesized earlier, they originate at the mantle-core boundary, rise almost vertically, and (closer to surface) get distorted by the same horizontal convection currents that drive plate tectonics. It’s our best description of plumes to date, arriving at the surface 50 years after Tuzo Wilson’s first puff of air from his eerie creek bottom.

 

Posted in History, How Geophysics Works, Non-drift Theories, People, Plate Tectonics | Tagged , , , , , , , | Leave a comment

Earth Expands on Mystery Diet

Not long ago, a reader of this blog commented on my story about Alfred Wegener and continental drift. Wegener’s theory, you know, kicked around for about 50 years before enough evidence accumulated to prove its sister theory, plate tectonics. The reader asked if I am “no fan of the Neal Adams’ Expanding Earth videos, then?” No, I’m not a fan of the great cartoonist’s geofantasies. But Adams’ videos are popular. One has over two million views on YouTube. Not a bad take for a purely bonkers pseudo-science video called “Neal Adams – Science: 01 – Conspiracy: Earth is Growing!”

Neal Adams is a notable creative force in comics. He modernized the art and inspired a generation of cartoonists. He championed the creators of Superman (Jerry Siegel and Joe Shuster) and helped them received awards, recognition, and pensions. Neal Adams is a fine cartoonist. He changed the look and style of Batman, Superman, and Green Arrow.  He has been called “the greatest comic book artist alive” – a statement that Adams himself unabashedly repeats on his own website. He is epic with pen and pad, but he is wrong about geology.

Adams’ video, Science: 01 – Conspiracy, begins with Richard Strauss’s Also Sprach Zarathustra which adds melodrama to his pseudo-science film.  But instead of authenticity, the pretentious soundtrack made me laugh. Whenever you hear Strauss, you know that something of great importance is about to unfold. It’s like the alert siren used on public service announcements. In this case, it’s a call to don your tin hat and prepare to hear about yet another science conspiracy – this time, it’s geophysicists hiding the truth about the evolution of the Earth.

Well, it looks like the world’s greatest comic book illustrator has unmasked us geoscientists. For years, we’ve been gathering in dark parkades, exchanging stuffed envelopes of incriminating geophysical formulae. Our goal: to promote the idea of plate tectonics, thereby gaining mastery of the universe. A minute into his video, Adams tells us “There is a kind of conspiracy of science among certain scientists. They know, but are not telling you, that…”  Well, you can watch the video for yourself to see what we know but are not telling you.

Mr Adams would like us to believe that the Earth is rapidly expanding. If you imagine a small balloon with (Hey, look!a squirrel drawn on it,  the eyes of the squirrel drift apart as you add more air. The Expanding Earth Theorists believe the same is happening to our planet, except eyeballs become continents and mystery substances replace air. Our planet Earth fattens because . . .  darn, I didn’t give Mr Adams $5 for his PDF, so I don’t know how to finish this sentence. (But you may go to his website and buy the $5 answer for yourself.)

Drop into Neal Adam’s alternate reality website, nealadams.com, and you’ll be treated to the opportunity to buy his PDF as well as a couple dozen videos explaining his version of the Expanding Earth Theory. Before you do, though, you might want to become familiar with past iterations of the theory. You see, the idea of an expanding Earth has been around since the time of Sir Francis Bacon who (over 400 years ago) wrote that the Earth looks like an expanding flower blossom, as evidenced by the way the African and South American continents have apparently parted.

Heezen and Tharp's Rift Map, 1957.

Heezen and Tharp’s Rift Map, 1957.

In 1909, professional musician Roberto Mantovani wrote a popular  science piece about the Earth expanding. More recently, a series of scientists put their voices to the idea. In the 1950s, Bruce Heezen (who inadvertently helped prove plate tectonics), co-discovered the great mid-ocean rift. He felt that the rift proved that the Earth was breaking and cracking as it expanded. His partner in science, Marie Tharp, believed they had found the source of continental motion and the cradle of oceanic crust. New crust formed at oceanic rifts, pushed the continents apart, then merged into the mantle at subduction zones. She was right; Heezen was wrong.

Another bright geologist/geophysicist who promoted expansion theory was the Australian Warren Carey. Carey adopted the hypothesis of planetary inflation early in his career and advocated it with congenial vigour. Well liked, correct about many things, but rejecting plate tectonics, he clung to expansion as the explanation for the odd way that fossils and rock formations are distributed around the world.  Late in his life, he continued to attend conferences and held court with a dwindling number of like-minded expansionists. Warren Carey, like Neal Adams, fell into the trap of promoting expansion while rejecting plate tectonics. It is not necessarily an either/or situation. Perhaps both drift and expansion are true.

Is our planet expanding? Maybe. A Hungarian geophysicist, László Egyed, calculated that due to internal chemistry, the Earth’s radius increases by a millimetre, or less, each year. That’s imperceptible within the lifetime of a human, who may live on a planet that grows only a single hand’s width in a hundred years.

Model of layered Earth: cooling may result in boundary phase changes.

Model of layered Earth: cooling may result in boundary phase changes.

The cause of expansion, said Egyed, is a change in the materials at the hot boundaries between the inner core, the outer core, and the mantle. Expansion, by his theory, occurs along those adjacent zones.  At each phase change, the Earth’s inner stuff becomes less dense. It expands. Egyed seems correct about those phase changes. They may really be happening, with inner core morphing into outer core, and outer core into mantle. If so, the planet might expand a millimetre a year.

If Egyed is right, our planet’s rotation must slow so that angular momentum is conserved. The Hungarian geophysicist proposed a geomagnetic test, but the results are not yet clear. So far, geophysicists aren’t sure that our planet has expanded as Egyed suggested, but there is no conspiracy rejecting the idea. Instead, it’s examined and studied – as are any credible scientific theories.

But expansion without plate tectonics can’t explain what we see on the Earth’s surface. For example, only plate tectonics accounts for the fact that the oldest seafloor is 180 million years old. Older ocean crust has subducted into the mantle.  To account for the young age of ocean crust, expansionists say expansion just started 180 million years ago. Most expansionists think the planet has doubled in size within this brief window. Neal Adams rejects subduction, but he’s wrong. There is no doubt that heavy ocean crust is pulled under lighter continental crust at subduction zones. Geophysical data from three lines of evidence (gravity, GPS, and seismic) overwhelmingly prove subduction.

What about Neal Adams’ idea that scientists conspire against him? It is hard to seriously study Adams (or anyone else) when part of their argument is that a group of us is quietly withholding secret knowledge about the way the world really works. Real science is quite the opposite. Scientists relish the idea of discovering that a theory is wrong. During the 1960s 70s, and 80s, hundreds tried to disprove plate tectonics. There is no better way to make one’s name than to revolutionize a field. But you’d better have the data to prove your idea.

Neal Adams, in an interview that you can hear at this link, says continents have not twisted and turned, Pangaea never existed (“Everything about the Pangea theory is wrong scientifically. Everything is wrong.”), the Earth has more than doubled in size, mountains didn’t exist until 80 million years ago, subduction is physically impossible, and plate tectonics is wrong. On all of this, Mr Adams is mistaken. Sadly, in the interview, you will hear him give the wrong ages of oceans and mountains, incorrectly explain the evolution of fish, and show a total lack of knowledge about sea salinity and salt domes. Neal Adams’ breadth of misinformation is impressive. So is the fact that over two million people have watched his science video.

We have empirical data – facts, not speculation – confirming continental mobility. These data come from real-time GPS measurements of the crust. Discrete plates twist and turn along paths that confirm plate tectonics and reject the simplified expansion model used by Adams. That does not mean that some expansion is impossible.

But the overwhelming data says that Neal Adam’s theory is incorrigibly false.  As Batman and Robin said, “Boom! Bash! Bang!” – continents collide tectonically, crust subducts, and the cartoonist is wrong.

Posted in Geology, Non-drift Theories, Plate Tectonics | Tagged , , , , , , , , | 2 Comments

Cuba, America, and Oil

With America’s president visiting Cuba this week, I thought it might be helpful to re-post my story “Has Cuba Got Oil?” which I wrote in 2014.  It’s still valid. Cuba still has oil. But I argued that I doubt oil has much to do with normalization of relations between the USA and the tropical island. Cuba’s oil – and there may be quite a bit – is hard to find and even harder to recover. So, petroleum likely has little to do with the pending American-Cuba reconciliation . Here’s my original blog post on Cuba’s oil . . .

Havana lawyer, Dr Fidel Castro, in Washington DC, 1959.

Havana lawyer, Dr Fidel Castro, visiting Washington DC in 1959.

Besides sunshine and sugar cane, what has Cuba got? It looks like the USA is serious about letting Americans party along Havana’s beaches and carry home a cigar or two. It has long bemused me that two of the continent’s closest neighbours have been isolated for two generations, with nary a neighbourly howdy between them. I can understand the American disdain when Castro turned to Russia for help and converted his island into a Communist dictatorship instead of a socialist democracy. But I can also see the point that others have made – sometimes an obstreperous foe’s behaviour changes more quickly by talking rather than isolating.

Let's concentrate on geology

Let’s concentrate on geology

This geology blog tends to steer clear of politics, so instead of pitching my three cents worth of non-expert opinion about embargoes vs free trade, I thought I’d write a few words about Cuba’s major oil fields. There really aren’t any elephants – not yet. Some readers may be surprised by the fact that the politics of oil exploration seems to play no role at all in the new American-Cuban detente.

Cuban village

Cuban village life south of Havana

Three geologists whom I know – Canadians working for three different companies – have spent time exploring Cuba’s subterranean oily treasures. They discovered very little oil, though one found a wife and settled into village life south of Havana. Nevertheless, there is oil within Cuba’s domain – the US Geological Survey estimates billions of (mostly offshore) barrels are awaiting discovery. Unfortunately, after drilling deeply in 2012 just off the north Cuban coast, hopes for the discovery of big oil fields were dashed. At least for now.

Things that make an oil field include source rock (usually oily shale), porosity (fractures and cracks that deliver hydrocarbons to the well), and traps (which can be ancient buried reefs, sand bars, pinched thrust sheets, or a bunch of other structures). There’s much more to an oil field than this, of course, but without a source, porosity, and trap, you’d better keep your derrick stashed in the shed at home. The things that make an oil field economical are the cost of production (depth of well, rock type, existing infrastructure), nearness to market, and the rule of law within the jurisdiction. How does Cuba stack up among these?

Well, all the elements that could create a profitable oil field actually exist in Cuba. The country itself has amazingly varied geology with plenty of source rock and plenty of traps buried in its highly structured geology, although the porosity element is sometimes problematic. Oil seeps were discovered centuries ago – strangely, though, the oil drips from igneous rocks, not the typical sedimentary limestones and sandstones that usually host hydrocarbons. An American Association of Petroleum Geologists’ 1932 paper, Occurrence of Oil in Igneous Rocks of Cuba, estimated that over 200 million barrels of “asphalt grade” oil was locked in rock along the north-central Cuban coast. In places, the heavy oil seeps from intrusive diorite dikes which have cut through 1,500 feet (500 metres) of oily Jurassic limestone and shale. All of this bode poorly for the explorers of the 1930s and it still does today. It means the hydrocarbon setting is complicated and unpredictable – and much of the oil itself is not much better than low-grade tar.

Regardless the US Geological Survey’s prediction of massive potential, Cuba has been energy-starved for a century. To fix this, Cuba famously entered into a deal with Venezuela, shipping well-regarded Havana-trained doctors south in exchange for South American oil. This worked well enough as long as Hugo Chavez was alive, but the flow may be stanched. Cuba needs to pump its own oil. Consumption has been around 155,000 barrels per day; production is one-third that. The shortfall has been purchased or bartered from Russia and Venezuela, but this creates a foreign expense of $5 million dollars a day – about $0.50/person in a country where daily income (GDP/pop) is a dismal $6. Both Russia and Venezuela are former big-bucks oil-ogarchies and were generous benefactors when oil prices were high. But things have changed. Those former sugar daddies have turned into sugar duds.

A Dog's Breakfast of geological puzzlement - USGS Cuba Structure Schematic

Dog’s Breakfast of Geology – USGS Cuba Structure Schematic

With the help of seasoned foreign geologists, Cuba has tried to produce its own oil. A very capable Canadian company – mining giant Sherritt International – explores and develops much of the country’s onshore oil. Sherritt is the largest independent oil producer in Cuba. But there is not an enormous amount of onshore oil. The real prize is waiting off the north coast – that’s where the USGS estimates 4.6 billion barrels of oil will eventually be produced. (The Cuban government claims the number is 20 billion barrels – but they are looking for investment partners.) Deep sea oil is not seeping to the surface – it is locked in rock deep below the ocean floor. Even though Cuba is near huge deep-water oil fields in the Gulf of Mexico, the geology under Cuba’s waters is remarkably different. The sticky prize is under 300 metres of seawater, then beneath 8,000 metres (25,000 feet) of twisted, faulted, thrusted rock. Geologists have a technical name for the jumbled thrust sheets that hold Cuba’s submarine oil – they call such formations a dog’s breakfast. It’s not pretty.

Not far from Cuba’s bit of the Caribbean are Gulf of Mexico oil platforms – some of which each produce 200,000 barrels a day. That’s more than the entire country uses. Large reserves are also under Cuba’s water, but so far none of it has been pumped to the surface. A recent casualty in the deep drilling effort was the Spanish oil company Repsol. After years of seismic exploration and testing under the tropical waters, Repsol gave up in 2012. Others have been poking holes in the Cuban exploration blocks – Brazil’s Petrobras (sometimes considered the world’s expert at deep marine exploration), Russian companies Rosneft and Zarubezhneft, as well as Norwegian, Indian, and Malaysian companies. All have given up on their offshore projects. Venezuela’s national oil company continues to be supportive, but can’t afford to drill the deep tricky wells off Cuba’s coast. Because of the 50-year embargo, American firms have not been involved at all – even though the huge Florida market for the offshore hydrocarbons is only a hundred kilometres to the north.

Greatly complicating things for Cuba, the drop in oil prices has further driven deep sea exploration projects from the stage. Low prices force drillers away from risky targets because the potential for a big financial return is too small. It must be frustrating for the Cuban people to own a non-recoverable resource that even the Americans assess at a $250 billion value. Because of the stubbornly unyielding deep sea reserves, Cuban leaders have refocused their efforts to the original fields – the proven onshore resources that already supply a chunk of the country’s oil. The Cubans have also begun focussing on solar, wind, and biomass energy (garnered from sugar mill waste) in earnest. Cuba’s vice president, Marino Murillo, recently told his parliament that Cuba plans to invest $3.6 billion over the next 15 years to develop alternative energy.

Oil well on Cuban beach

A safe oil well on a Cuban beach

This might be good news for Cuba’s growing tourist industry – oil production lies very near Havana and Varadero and is found on beaches popular with Canadian and European winter holidayers. The threat of leaks and spills worries Cuban residents as well as foreign resort developers. Cuba’s inadvertent switch away from deep sea oil exploration towards other energy schemes reduces their anxiety a bit.

The bottom line to this story is that Cuba and the States may become friendly neighbours but oil is not the reason. Someday the potential offshore Cuban oil reserves may be drilled, but with the current low price of oil and with the difficult geology of Cuba’s thrust and fold belt, development is decades into the future. By then the other elements that make an oil field – including lower cost of production and rule of law – will hopefully be ingrained features of the Cuban business environment.

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Broken Crystals

Rene Just HauyEvery now and then, I write a short post on a long-dead geologist whom I had never heard of before, but have discovered that it’s their birthday anniversary. I do this because it forces me to learn something about someone who perhaps deserves remembrance. And it gives a nod of appreciation to the hammer and chisel folks who came before us. Today we salute  René Just Haüy, born February 28, 1743. He’s a fellow who broke things.

By discovering the geometrical law of crystallization, this French mineralogist is considered  the founder of crystallography. I should hate the man. His discipline created a required university course that was my Achilles’ heel, knee, and thigh. As a colour-blind person, and someone who often mistakes his lampshades for his wife,  recognizing minerals and crystals was brutal for me. By I digress. Today, I honour Father René Just Haüy.

Calcite crystals growing on fossil shell. (Source; Wikipedia)

Calcite crystals growing on fossil shell.
(Source: Wikipedia)

In 1781, the klutzy priest accidentally dropped a valuable calcite crystal that belonged to a soon-to-be ex-friend. The crystal broke into rhombohedral pieces. In rage – or more likely, scientific curiosity – Haüy deliberately broke variously sized crystals of calcites and found similar rhombohedral pieces locked inside each one, like little Kinder surprises. He concluded that molecules of calcite always have the same basic shape, regardless of their size and general outside appearance. Further, he discovered that many other minerals also have basic structures particular to their species – six primary shapes in all. He realized that this meant different classes of minerals have different (but self-similar) angles on their crystal faces. For that inference, he became famous.

Haüy described his mathematical-crystallographic discovery in Traité de minéralogie, leading to immediate induction into the French Royal Academy of Science. A few years later, the king’s mineralogist was thrown in prison by anti-monarch revolutionists.  He escaped execution when Étienne Geoffroy Saint-Hilaire (an evolutionary paleontologist) interceded on his behalf. A good thing, too, because Haüy soon discovered pyroelectricity, a geophysical property of some crystals whereby they acquire an electrical charge when heated or cooled. Nothing much has been done with this discovery yet, but some day it may prove to be a source of power in spacecraft in science fiction epics about aliens from crystal plants.

Eiffel Tower in 1888Keeping his head during the revolution, Haüy was later befriended by friends of Napoleon. In 1802, they appointed him professor of mineralogy at the National Museum of Natural History. There, Haüy founded the Musée de Minéralogie. However, being associated with Napoleon’s people was an honour that eventually backfired. He was stripped of his appointments by the Restoration government that replaced Napoleon. Haüy’s final days were depressingly impoverished. However, when the Resortationists disappeared, Haüy was again in favour. He lived to almost 80, boarding the great celestial crystal cruise (or more likely, not) in 1822.  Securely back in vogue, Haüy’s name was one of just 72 inscribed on the Eiffel Tower. However, his name will probably disappear again when the iron tower is replaced by something more aesthetically pleasing.

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Charles Darwin, the Geologist

I don’t often reblog, but it’s Darwin’s birthday. So I am repeating this piece from one year ago today. Have a slice of cake while you read it!

The Mountain Mystery

Ridiculing Darwin, Hornet magazine 1871Darwin as imagined by Hornet magazine 1871

It’s his birthday. It seems Charles Darwin’s legacy is experiencing a renaissance. Sure, some 60% of Americans vilify the man and hope he is roasting in hell. Or undergoing reincarnation as a toad, or is still awaiting release from purgatory. I guess that the eternal damnable punishment for writing a pretty good book depends on one’s own vision of a just and loving supreme being. Darwin has somehow caught the heat and hate of a lot of people who have trouble with scientific inquiry – and where such inquiry may lead.

Nevertheless, few scientists were as meticulous, thoughtful, and cautious as Charles Darwin. Though we celebrate his ideas of natural selection, survival of the fittest, and the origin of species, the idea that biology continually sorts and rearranges itself evolved slowly in the years before Darwin. The notion of evolution became evident to…

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Wegener’s Death and Drift’s Hiatus

Alfred Wegener, 1930, in Greenland

Alfred Wegener, 1930, in Greenland

Over the past few days, I’ve written about Alfred Wegener’s continental drift theory, which is celebrating its 100th year as a spunky idea that explains a lot of our geology. From mountains to earthquakes and deep sea rifts to island arc volcanoes, it’s all tied together in plate tectonics, which began just over a hundred years ago as continental drift.

If you’ve been following my past week’s  posts, you saw Alfred Wegener enter our story as a meteorologist, you saw how fossils and climate inspired his theory, then looked at the publication of Wegener’s papers and book  between 1912 and 1915, and yesterday, you read about the ugly rejection of his drift theory.  Now I’d like to give you a bit about Wegener’s death in Greenland and its immediate impact.

NYT headline

March 30, 1930 – NYT

Wegener was on his fourth scientific expedition to the Arctic and he was director of the Danish-Greenland polar research camp. He was much better known around the world for his northern exploration than for his relatively obscure ideas about drifting continents. In fact, the New York Times covered his departure at the start of Wegener’s last trip and charitably did not mention his drift theory at all in their lengthy science article.

Wegener’s fourth mission to Greenland included testing a new seismic method to measure the thickness of the icecap that covered the island. He believed it was much thicker than the assumed 3,600 feet previously measured. Sending sound waves into the ice and timing their returning echoes with seismic equipment would give him a better estimate of the icecap’s thickness. The expedition also involved preparations to establish a permanent station that would gather continuous meteorological data. But food shortages, extremely cold weather, and unpredictable blizzards put outlying camps at risk.

Alfred Wegener and his colleague Rasmus Villumsen were last seen on Wegener’s 50th birthday, November 1, 1930.  The day following his birthday, Wegener and Villumsen set off  to deliver supplies to a small outlying camp which had been cut off by foul weather. The two were overtaken by a blizzard. Wegener’s body was not found until the following spring, on May 12, 1931. He was lying upon a reindeer hide, placed there by Villumsen, who was never found. When news of his death reached the world, it was front-page news. The New York Times headline read: “Wegener Gave Up His Life to Save Greenland Aides; Left So Food Would Last”.

Fritz Loewe, right, suffering frostbite

Fritz Loewe, right, suffering frostbite

Upon Wegener’s death, leadership of the Greenland expedition passed to his friend Fritz Loewe. Loewe had trained as a lawyer in Berlin, but developed a passion for science and exploration, earning a PhD in physics. He became a meteorologist and understudy to Alfred Wegener. Before the expedition, Loewe had earned the Iron Cross as a young soldier in the German army and had already spent time in the arctic.

During the fatal 1930 expedition, Loewe’s feet froze and a colleague at their Greenland camp clipped off nine of Loewe’s toes with tin-snips and a pocket knife to avoid gangrene. Returning to Germany, Loewe, a Jew, was soon dismissed from his post with the Meteorological Service. He left with his wife and two young daughters for England. He finally found permanent work, in 1937, as a lecturer in Melbourne, Australia, where Loewe co-discovered the southern jet stream. Few students knew the remarkable background of their professor with the awkward gait who clomped the university corridors for 25 years.

Following Wegener, only a handful of geologists were willing to inherit the orphaned continental drift theory. Arthur Holmes, Alexander du Toit, and Reginald Daly spring to mind. They all believed the data and accepted the theory, but they each had busy jobs as geologists – proving drift theory was an interest, but neither an occupation nor obsession. Drift theory did not take a complete hiatus, but the years between 1930 and 1955 saw very few converts to the cause.

Arthur Holmes, 1912

Arthur Holmes, 1912

Arthur Holmes was born on the moors in north England and educated in London At age 20, he discovered a way to measure the age of the Earth using radioactive decay. He was the first to know that the planet is over a billion years old. Then he figured out mantle convection and claimed that this was the power source that Wegener needed to make the continents drift. The final chapter of his 1944 book, Principles of Geology, is about the mobility of the Earth’s crust. It has the first drawing of the mantle convecting and includes this line: “Currents flowing horizontally beneath the crust would inevitably carry the continents along with them.”

Alexander du ToitAlexander du Toit was a South African geologist who quickly accepted Wegener’s theory. Some consider Du Toit the greatest field geologist who ever lived. From 1903 to 1910, he travelled the whole of southern Africa on foot, ox cart, and bicycle with a mapping table slung over his shoulders.  In 1923, he was awarded a Carnegie Institute grant to travel to South America to test his thesis that rock formations that ended on the edge of Africa picked up precisely the same in Brazil. They do, convincing him that continents had once been joined and have drifted apart. Alexander du Toit wrote Our Wandering Continents in 1937 and dedicated the book to Wegener’s memory.

Reginald DalyReginald Daly, a Canadian who headed Harvard’s geology department, was a renowned field geologist who visited dozens of countries and every American state (except South Dakota) at least once. His expertise was basalt (“no rock type is more important to the Earth”) and he recognized ocean crust was heavy basalt while continents were mostly lighter granite. Quite early, Daly agreed with continental drift and supported the idea with data he personally gathered around the world. He mischievously put the words E pur si muove! (“And yet, it moves!”) on the cover of his 1926 book, Our Mobile Earth.

I’ll write more, in a few weeks, about Holmes, du Toit, and Daly. They each deserve to have their stories told. They kept the idea of mobile continents alive when almost no one believed them.  Besides Holmes, du Toit, and Daly, there were only a few other geologists during the 1930s and 40s who supported crustal mobility theories. Overwhelmingly, established geologists were convinced that the Earth’s continents were immobile.  It would take another thirty years before geologists accepted continental drift – modified as plate tectonics. Only then would the names of Alfred Wegener and the others inspire courage of convictions, rather than serve as a stark warning against breaking with scholarly tradition and dogma.

Science, they say, progresses one funeral at a time. This is especially true about the gradual acceptance of plate tectonics. But there is an unspoken (and unknowable) corollary. Science is sometimes stalled by a single death. We will never know how continental drift would have evolved had Wegener not died in Greenland. Had he lived to 1967, the year that nearly all geologists accepted plate tectonics, he would have been 87 years old. He could have lived to see the transition and perhaps even have sped its arrival. We will never know.

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100 Years of Drift: Part 4

Today, we continue with Alfred Wegener and his continental drift theory. Today’s piece will not be pretty.

At times, suppression of Wegener’s idea was ugly. There are a lot of reasons for the vilification. He was an outsider, a meteorologist who tried to revolutionize geophysics. His scientific technique was not really science, but seemed to harken back to the age of Aristotle, a time when logical conclusions were drawn from observations without much experimentation.  Recent historians have said that Wegener represented a regressive sort of science that was not as open and egalitarian as multiple-hypotheses American science was rumoured to be. Wegener was a World War I veteran who fought on the ‘wrong’ side of the bitterly divisive war, leading to astringent assaults and thinly veiled insults. His uncompromising persistence was interpreted as arrogance.

In today’s entry, we’ll review all of this and see why it would take another 50 years before continental drift morphed into plate tectonics and was finally accepted.

As we saw yesterday, Alfred Wegener build a strong circumstantial story that the continents move. It was based largely on paleoclimate and fossil evidence. However, there were problems with both his story and his presentation.

heavy-loadWegener had a strong-willed personality, was selective in his choice of examples, had no formal background in geology, and showed little apparent appreciation for the work and traditions of established geologists. Meanwhile, earth scientists pointed out the most serious flaw in Wegener’s grand idea – continents couldn’t be moved by any force weaker than God.

He suggested that continental drift was due to tidal action from solar and lunar gravitational forces, but physicists quickly proved those forces were too weak. Wegener had a theory that explained how fossils came to be distributed, but he had no way of explaining how continents themselves came to be distributed. We know now, of course, that convection currents spread oceanic rifts and create subduction zones that move the continents and create and devour crust. This idea had never occurred to Wegener nor to his contemporaries.

Scientists who glanced at Wegener’s thesis felt he was arguing that the continents sail around the oceans. A colleague, the respected geologist Franz Kossmat was particularly unconvinced. He had published over twenty geology and mineralogy books and lectured for thirty years in Graz and Leipzig. He is remembered as the first to dismiss Wegener’s continental drift in writing, insisting oceanic crust is too firm for continents to simply plow through.

In 1925, French geologist Pierre Termier said continental mobility was “a beautiful dream, the dream of a great poet. One tries to embrace it, and finds that he has in his arms a little vapour and smoke.”

In Britain, a year after the first English translation of Wegener’s Origin of Continents and Oceans, Philip Lake said this about Wegener at a meeting of the Royal Geographical Society: “He is not seeking the truth; he is advocating a cause, and is blind to every fact and argument that tells against it. It is easy to fit the pieces of a puzzle together if you distort their shape, but when you have done so, your success is no proof that you have placed them in their original positions. It is not even a proof that the pieces belong to the same puzzle or that all the pieces are present.”

British geophysicist Sir Harold Jeffreys was especially unyielding, certain that the crust’s rigidity made continental drift impossible. His influence was enormous. His disciples denounced Wegener’s hypothesis for decades and lugged Sir Jeffreys’ animosity into fifty years of future debates against plate tectonics. Jeffereys himself lived to 1989, dying at age 98, long after plate tectonics was mainstream – but still opposed the idea.

But most European geologists were reserved in their criticism. It was in America that Wegener was most severely berated.

“Utter damned rot,” said William Scott, geology professor at Princeton (and President of the American Philosophical Society) in 1923, describing the theory of continental drift. Edward Berry, an American palaeobotanist, called Wegener’s theory “a selective search through the literature for corroborative evidence, ignoring most of the facts that are opposed to the idea, and ending in a state of auto-intoxication.” Bailey Willis, a renowned earthquake seismologist and geologist for the US Geological Survey, reportedly said “further discussion of it merely encumbers the literature and befogs the minds of fellow students. [It is] as antiquated as pre-Curie physics. It is a fairy tale.” Willis also claimed Wegener was more “an advocate rather than an impartial investigator.”

Although the American geologists never took their fight to the streets, there opposition to continental drift was spirited.

American geologists never actually took their fight to the streets, but opposition to continental drift was spirited.

America was the hotbed of anti-drift hostility. Ralph Chaney, an American expert on plant fossils and ancient climates, wrote “It is amusing to note that in taking care of their Tertiary forests, certain Europeans [Wegener] have condemned our forests to freezing.” Chaney dismissed Wegener’s palaeoclimatology as amateurish, apparently unaware that Wegener, with his father-in-law Wladimir Köppen, wrote the world’s primary textbook on the subject. Others, such as Chester Longwell of Yale, rejected the concept of mobile continents in the 1920s and stayed opposed into the 1960s, even as the evidence became overwhelming. In 1968, Longwell sniffed, “Although partisans favoring drift may have been right, they based most of their case on the wrong reasons and were unable to visualize a mechanism.” His statement rings of revisionist history with a touch of sour grapes.

Many in the States were opposed to the climate scientist’s theory, but the most powerful opponent to Wegener’s idea was Rollin T. Chamberlin, a geologist at the University of Chicago. He was also editor of Science and a founder of a philosophical society. Chamberlin wrote about drift, “Can geology still be considered a science if it is possible for such a theory as this to run wild?” Later, in 1928, Chamberlin quoted an unnamed colleague, “If we are to believe Wegener’s hypothesis we must forget everything which has been learned in the last 70 years and start all over again.”

1928 aapg coverTo deride the idea, the Americans branded the theory as continental drift, though Wegener referred to his idea as Die Verschiebung der Kontinente, literally, The Displacement of the Continents. By 1928, the Americans had renamed the displacement process as continental drift, conveying a more whimsical sense. They used the phrase as the title of a collection of papers presented at a symposium sponsored by an oil explorers’ organization. As continental drift, the derision was clear. The American Association of Petroleum Geologists (AAPG) symposium seems to have been organized primarily to discredit Wegener and the few other proponents of his theory of displaced continents. The AAPG published the collected papers in a volume which has become a permanent record of the many New World scientists who rejected displacement and even engaged in personal attacks against Wegener.

One of the most aggressive anti-drift scientists at the AAPG gathering was Charles Schuchert. His presentation included a clay model of the continents. He slid it around in front of his audience, showing that the continents could never fit together into a supercontinent. The illustrations, British geophysicist Edward Bullard said much later, “were so bad that it is difficult to trace the reason for this extraordinary and quite false result.” Schuchert said an unnamed friend thought the fit of Africa and South America was “made by Satan” to confuse geologists.  Schuchert also had a troubling habit of referring to continental drift as “that German theory.”

Twenty years after the AAPG conference in New York, continental drift was still generally rejected without discussion, said film producer David Attenborough. He attended a British university in the late-1940s. In a 2012 interview, Attenborough recalled asking one of his lecturers why continental drift wasn’t being discussed. He says, “I was told, sneeringly, that if I could prove there was a force that could move continents, then he might think about it. The idea was moonshine, I was informed.”  Thirty years later, Attenborough presented some of that moonshine in his 1979 series, Life on Earth, demonstrating the evolution of life and planet.

Historian Naomi Oreskes suggests that a lot of the American animosity to Wegener and his drift theory stems from cultural differences in the way science was pursued. She points out that a prevailing scientific philosophy based on multiple working hypotheses “reflected American ideals expressed since the 18th century linking good science to good government. Good science was anti-authoritarian, like democracy; good science was pluralistic, like a free society. . . And if good science was a model for a free society, then bad science implicitly threatened it.”

And there was the personal aspect. Geophysicist Bullard observed, “It is interesting to consider why Wegener’s arguments did not carry conviction, since it is now clear that many of them are, in principle, sound. The reasons were, in part, associated with the nature of Wegener’s presentation. He argues too hard and was often accused of advocating a cause rather than seeking truth.”

Dismissing continental drift theory as simplistic, Chester Longwell suggested that for advocates of the idea, “a definite choice of creed brings some peace of soul that is denied to the scientific skeptic.”  It was not the last time Wegener’s theory would be described as a pseudo-scientific cult. But there may have been more to the disdain for Wegener’s theory. Rarely mentioned, but sometimes alluded to, is the fact that Wegener had been a German soldier. Americans such as his fierce critic Longwell had once had Wegener in their cross-hairs. Captain Longwell was a graduate student at Yale when the Great War broke out. He spent part of his two-year army service overseas where “his composure under unusual circumstances made all officers of the regiment admire and respect him.” The ugliness of the Great War cannot be overstated.

Wegener, his wife and daughter, 1916

Wegener, his wife and daughter, 1916

During their advance into Belgium, Wegener was shot through the arm. After two weeks in hospital, he was sent back to the line and hit again – this time a bullet lodged in his neck. Finally, the directors of the German Army sent their great scientist off to work in the meteorological service.  After the war, both sides sought cooperation in the sciences, but it did not help Wegener that his methodology displayed “cultural differences.” His theory languished on the edge of acceptability for years. Geologists saw no evidence that Greenland was trudging away from Europe at a rate of two or three metres per year, as Wegener had suggested. They argued continents are not strong enough to plow through ocean crust yet weak enough to buckle into mountains. And there was the lack of a strong force able move continents.

The idea of mobile continents passed from a peculiar notion to a real scientific theory when Alfred Wegener suggested that scientists might be able to measure the pace of continental motion. This was a testable question for his hypothesis. Measurement would authenticate his theory, he said. Using old, but unreliable maps, Wegener estimated North America and Europe are separating at a rate of 250 centimetres each year. Wegener was wrong, the actual velocity is a hundred times slower. Wegener thought astronomical measurements would eventually become precise enough to measure the growing gap between Ireland and Newfoundland. He optimistically expected new techniques “will soon remove the last doubts about the reality of this movement.” But when newer data arrived a few years later, it neither confirmed nor denied continental drift.

Wegener would not live long enough to see his theory proved. Measurements made in the 1980s finally confirmed his wild notion. Laser beams bounced between widely-separated pylons, charting continental drift. Recently, Earth-orbiting satellites have since marked the movement with a  precision unimaginable in 1912.

After Wegener’s death, a trio of scientists kept his drift theory simmering on the back burners of the science kitchen: Alexander du Toit, Arthur Holmes, and Reginald Daly. In future essays, I’ll give each of these scientists a voice. Tomorrow, we will look at Alfred Wegener’s immediate legacy and his last days, spent trying to help colleagues during a Greenland blizzard.

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100 Years of Drift: Part 3

wegener pipe outdoorsIn today’s blog post, we continue our story of the development of the theory of continental drift – an idea which just celebrated its 100th birthday. Before Alfred Wegener’s 1915 book on contintents in motion, a few others had the idea, yet no one had developed it as thoroughly. In Part 1 of this series, we covered a bit of Alfred Wegener’s early life and some of his initial work. Yesterday, we showed how fossils and palaeoclimate figured into his continental drift theory. Today, we continue with Wegener by looking at his idea in a little detail.

On Saturday, January 6, 1912, Wegener presented a lecture that unveiled his hypothesis of a supercontinent and the idea that it fractured into our modern continents. He gave his talk to the German Geological Society at the Senckenberg Museum in Frankfurt.  Probably no one in attendance believed his notion – they knew that the continents were fixed rigidly in place. Wegener finished to disinterested and polite applause. It was the sort of speculative lecture suited for the Saturday afternoon it was given. Graduate students listened, few questions were asked, and the meteorologist Alfred Wegener was expected to return to launching his weather balloons in Greenland.

Wegener_KontinenteBut three years later, in 1915, Wegener expounded upon his theory. He envisaged a grand unified continent, or Urkontinent, which once had held all of Earth’s life. Wegener had spent the previous three years quizzing acquaintances and gleaning geology journals for scraps of evidence – anything that would support his theory. It was backwards science – selectively enlisting information to prove a point. Later, he would be taken to task for this approach. However, by the time he published Die Entstehung der Kontinente und Ozeane (The Origin of Continents and Oceans), he had collected hundreds of examples of corroborating evidence related to continental movement, including:

1) The outlines of most continents fit together like a jigsaw puzzle;
2) There are geological similarities including mountain belts, river trends, ore deposits, and rock types along the Europe-North America and Africa-South America coasts;
3) Fossils of land vertebrates and plants extend across those same continents, though now separated by oceans; and,
4) Tropical plants once thrived in Antarctica while glaciers scratched striations, or grooves, into rocks in North Africa – occurrences best explained by continents moving across climate zones.

Kontinente_und_Ozeane mapThus, he presented Pangaea, his conglomeration of all the continents clustered into an ancient supercontinent. On Pangaea,  freely roaming lifeforms had scattered their fossils and mountain ranges and ore deposits were continuous. According to Wegener, some unknown force caused Pangaea to break up, separating fossils and ores alike. The old supercontinent’s pieces slid about on the Earth, arriving at the positions we are familiar with on today’s maps.

Although the circumstantial evidence was significant, without a massive power source to displace the continents, it was difficult for established scientists to seriously consider his idea. At the Frankfurt meeting, Wegener had said, “the forces that displace continents are the same as those that produce great fold-mountain ranges. Continental displacement, faults, and compressions, earthquakes, volcanoes, transgression cycles, and polar wandering are undoubtedly connected on a grand scale.”  They undoubtedly are, though Wegener had not discovered the mysterious forces.

Wegener described the continents splitting, gliding, wandering, and colliding but he could not propose any engine strong enough to propel them.  Nor could he explain why there were apparently no trails gouged into the seafloor behind the continents, scratched into the substrate as they plowed along. The idea that rigid, heavy continents could wander the Earth’s surface was preposterous to reasonable geologists. But Wegener continued sifting through the evidence that supported mobility. Over the next few years he followed his Frankfurt lecture with three papers and his 1915 book, which we have just noted. His Origins book – written in a popular and accessible style – was updated several times before Wegener’s early death, 15 years later.  In those revisions, he answered detractors and built his defense from his observations and his immense library of correspondence with geologists.

But Wegener the meteorologist was isolated and his idea received as much goodwill as most pseudo-science is given today (the difference, of course, drift would be modified into plate tectonics and eventually proven correct). Tomorrow, we conclude this saga and hear how one American geologist responded to Wegener: “Utter damn rot!” That sentiment, from a Princeton geology professor, was not a lonely debunking of Alfred Wegener. It was the nearly unanimous voice of reason that would prevail in earth sciences for another 50 years.

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100 Years of Drift: Part 2

It’s been 100 years since Alfred Wegener proposed his idea of continental drift. Today’s blog continues the story we began yesterday – the tale of Wegener’s life and the development of his grand idea of mobile continents. This time, we’ll look at the significance of fossils and climate and how these contributed to the drift theory. 

By 1900, most geologists and biologists accepted Darwin’s description of species evolution. Darwin noted that the offspring of various creatures, isolated from each other and exposed to different environments, evolve into quite different beings with the passage of time. For example, bison arose on the American plains while the wildebeest fills a similar ecological niche in Africa. Both form huge herds, mostly survive by grazing (eating grass and seeds), but also by a little browsing (munching on the odd shrub). Both animals have manes, wild beards, and both look like trouble.

2 beasts

But you would instantly distinguish a bison from a wildebeest. Significant changes have taken place in the millions of years since the two animals  shared a common ancestor. In addition, with very little practice, you would quickly discern the fossilized bones of each.  No African creatures evolved to exactly resemble the American bison and no wildebeest herd ever roamed the Kansas grasslands. Similar, but distinct – though they have common ancestors.

So it was hard to explain, a century ago, how fossils of absolutely identical creatures, such Lystrosaurus, Mesosaurus, Cynognathus, and a myriad of lesser fossilized animals (such as snails and lizards) could be found on separate continents. Geologists also observed fossils of the  tropical fern Glossopteris in Antarctica’s coal beds as well as parts of India, Africa, and South America. None of these lifeforms could swim an ocean. Without admitting a supercontinent’s former existence, rupture and subsequent drifting, it was difficult to explain how those plants and animals could have populated several remote continents simultaneously – unless the former continents were once merged in a unified land upon which they traipsed. Merged, like this:

continental drift creatures
Most geologists believed that some sort of land bridges, now sunken below the waves, had helped creatures (including plants and snails) roam freely between the continents. There are modern land bridge examples – Central America links the American continents, allowing migrations; Alaska and Russia have periodically shared a land bridge that animals such as horses, camels, and humans have crossed. This, with a stretch of imagination, could solve the problem of the distribution of fossils. However, by 1900, no signs of any long-lost sunken bridge between South America and Africa had been discovered. Nor between Newfoundland and Norway, nor Australia, Asia, and Antarctica, nor any of the other dozen places they were needed to account for fossil similarities. An alternative solution was to assume that the problematic fossils had arisen upon a single supercontinent which split apart, pieces drifting off to become autonomous landmasses, thus disconnecting those ancient plant and animal fossils in the process. But to most geologists at the time, drifting continents seemed highly improbable.

The person who best explained how fossils might have become scattered without the help of land bridges was not trained as a palaeontologist, botanist, nor even as a geologist. He was, instead, a polar explorer, a university professor, and a meteorologist. Although Alfred Wegener is at the heart of the theory that would eventually explain how fish fossils appeared on mountain slopes, he was not an Earth scientist.

Wegener was more comfortable on icy plains than mountain ridges. But as an outsider, he offered a fresh perspective on the Earth’s changing landscape. Wegener and other climatologists wondered aloud about tropical fossils (and coal deposits) discovered north of the Arctic Circle and ancient signs in the Sahara (rock scratches called striations, plus distinctive rock rubble) that could only be made by glaciers.

Before the Permian, 300 million years ago, there had been a hot swampy period with leafy foliage dominating the landscape and creating the billions of cubic metres of carbonaceous rocks – coal – that would eventually add smoke and energy to our industrial age. Today, those coal layers stretch around the world, even to Canada’s most northerly island, Ellesmere, just a few hundred kilometres from the North Pole. While others assumed the entire Earth was once tropical, Wegener’s explanation for coal in the arctic was continental movement. Wegener showed that all the land once clumped together into one large continent centred on the steamy equator where the coal developed. Then the landmass slid to extreme southern latitudes where it was covered by glaciers, like this:

Pangaea's proposed visit to the south pole. Lines indicate glacial striations.

Pangaea’s proposed visit to the south pole. Arrows indicate glacial striations.

Finally, Wegener broke his supercontinent into drifting pieces which distributed coal seams, fossilized coral reefs, glacial striations, and salt beds to places that are impossible in today’s climate. Continent mobility, as improbable as it seemed to geologists a hundred years ago, best explained such strange climate relics.

WegenerFor meteorologist Wegener, the world-wide distribution of ancient glacial remains such as till, drummonds, eskers, and especially striations, were compelling evidence that the continents had moved. Something very odd had happened to the Earth. The planet’s surface had been hot, then experienced a deep freeze at the start of  the Permian. Wegener noted glacial striations are found in North and South America, India, Asia, Europe, and even the Sahara. Such grooves are uniquely etched by the weight of glaciers as they drag stones across underlying rocks, leaving telltale scratches, or striation signatures. Nothing else causes them. This was a major problem for geologists. How could so many locales – including places on the equator – have been massively iced?

Unencumbered by colleagues or mentors attached to established geological precepts, Wegener weighed the evidence. His detachment enhanced his daring innovation, but it also made him a target for rejection, a rebel dismissed as an uninformed outsider producing misguided speculations. Ultimately, his contribution to geology led to the best model for explaining the Earth’s dramatic scenery. With Wegener everything – earthquakes, volcanoes, distribution of rocks, glacial debris, and fossils – falls neatly into place. He advanced the crucial theory that answered the most enigmatic puzzles about the Earth. But his big idea was rejected for fifty years. His contributions were only appreciated decades after his death in a blizzard on his final Greenland expedition.

We will continue our story about Alfred Wegener tomorrow when we examine his papers, his big idea – which he called continental displacement, but Americans translated more whimsically as continental drift, and his book, Die Entstehung der Kontinente und Ozeane (The Origin of Continents and Oceans). We’ll also begin to look at the extreme animosity that greeted his work.

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100 Years of Drift: Part 1

Alfred Wegener, in Greenland, 1930

Alfred Wegener, in Greenland, 1930  (photo by Fritz Loewe)

Fifty years ago, we finally figured out why the Earth has mountains. But one hundred years ago, Alfred Wegener had already offered an explanation – it took those extra 50 years for his grand idea to catch on. The continents, Wegener said, wander about. They bump into each other. Accidents cause mountains.

Yea, it’s been a hundred years since Wegener first wrote about continental displacement. A few other people had similar notions earlier. In the 1600s, Francis Bacon speculated that the southern hemisphere’s continents were arranged “like an opening blossom.” Some say Bacon was wondering if they had drifted from an original supercontinent, though Bacon never really said that.

In the 1800s, a few notable geologists (particularly Antonio Snider-Pelligrini, in France, and Richard Owen, in the USA) claimed that the continents were mobile. But their cases weren’t as compelling as Alfred Wegener’s, whose idea was compelling, but also derided, ridiculed, rejected, denounced, smeared, and otherwise not taken too seriously by anyone anywhere. Over the next couple of blog posts, we’ll give Wegener’s theory a bit of an airing.

Snider-Pelligrini's 1858 map of continental drift

Snider-Pelligrini’s 1858 map of continental drift

Alfred Wegener, born November 1, 1880, in Berlin, was the youngest of five children in a middle-class family. His mother, Anna Schwarz, and his father, Richard Wegener, lived in Berlin Mitte, the city’s main centre and cultural and intellectual hub.  The elder Wegener taught classical languages and lectured as a theological philosopher. (Some popular histories make much of Wegener’s father, describing him as “an evangelical preacher.” In 1880s Germany, non-Catholic Christians were usually called ‘evangelical‘. The senior Wegener wasn’t a preacher, he taught theology.)

Humboldt University

Humboldt University in Berlin

Young Wegener studied at nearby Köllnische Gymnasium, where he ranked first in his school in everything, particularly excelling in physics. Afterwards, he studied in Berlin, then Heidelberg, and Innsbruck. He returned to Berlin’s prestigious Humboldt University where philosopher Walter Benjamin and physicist Max Planck, as well as Albert Einstein, Karl Marx, and Friedrich Engels had all been either instructors or students. During graduate studies, Alfred Wegener assisted at Berlin’s Urania Astronomical Observatory.

30-year-old Alfred Wegener in 1910

30-year-old Alfred Wegener in 1910 (photo credit)

Although armed with a PhD in astronomy, Wegener acquired an interest in climatology. He took a position at the Lindenberg Observatory where his older brother was already a meteorologist. Among other duties, Kurt and Alfred Wegener pioneered weather-balloon tracking of storms. They also tested a new celestial navigation quadrant by climbing aboard experimental balloons. One of their flights, in April 1906, set a record for the longest time anyone had ever been airborne – they spent 52 uninterrupted hours floating above Europe.

Also in 1906, Wegener was invited to join a Danish expedition to Greenland. It was the first of his four field studies on the frozen island. He later regarded the expedition as a turning point in his scientific career – exploring the  arctic became his great passion. Greenland offered opportunities for discovery. By the early part of the twentieth century, much of coastal Greenland had been charted, but there were remote unknown stretches along the northeast coast which he explored. The arctic experience tested Wegener’s resolve. His mentor and team leader died during the 1906 expedition while exploring Greenland’s interior by dog sled in conditions similar to those that would later take Wegener’s own life, 20 years later.

snug as spoonsWegener’s curiosity, and some of his Greenland observations, led him to stray into the unresolved issues of geology. He devoured  journals and corresponded widely with geologists. He admits he was seduced by the potential snug fit of the African and South American coastlines. In December 1910, Wegener wrote to his lady friend, “Doesn’t the east coast of South America fit exactly against the west coast of Africa, as if they had once been joined?” (She married the young romantic.)

After returning from the first of his four Greenland expeditions, Wegener spent the next six years lecturing cosmic physics, applied astronomy,  and climatology at the University of Marburg.  He was an unusually spirited professor – his students appreciated the small, energetic teacher who presented clear, organized lectures. His course notes were so well-formed that he was able to gather them into one of the first text-books explaining meteorology. His 1911 text became the standard climatology text for several decades and it was the first to include detailed observations and weather data from the Arctic.

As a result of his climate studies, Wegener noted evidence of glacial remains in the Sahara desert and tropical fossils north of the Arctic Circle. Consequently, Wegener developed his idea that the continents are in motion.  At first, Wegener claimed, he was unconvinced of his own theory. But in the fall of 1911 he stumbled upon a paper that listed fossil similarities between Africa and South America. Wegener pursued fossil distributions and palaeoclimate evidence. He finally concluded that the continents had split apart, plowed through oceans, and drifted to their present temporary positions. He saw the Earth’s surface as dynamic and alive with motion. He even thought he saw signs of continental drift when he compared his observations in Greenland with maps produced a few generations earlier. On January 6, 1912, Wegener took the risky step of publicizing his unorthodox thoughts about mobile continents. 

Tomorrow, we shall see the personal consequences of his continental drift idea and we’ll look at some of the fossils that helped lead him to his conclusion.

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