The pioneer who moved continents and uncovered oil
He died in 1930. His grave, in a remote part of the central Greenland ice cap, now lies under 100 metres of accumulated snow. His ideas were scorned in his own lifetime. But 2012 marks the centenary of the German meteorologist Alfred Wegener's theory of continental drift, now the foundation of modern geology. His insight continues to provide oil explorers with new discoveries even today, and explains the fabulous oil and gas wealth that underlies the Middle East.
Wegener proposed that, instead of being fixed as most geologists of the time thought, the continents gradually move across the Earth's surface, and oceans open and close. He asked why the traces of ancient glaciers are found in what is today the scorching Sahara Desert, and why the Scottish mountains are identical to those of Newfoundland in Canada.
He suggested the near-perfect fit of the coasts of Africa and South America shows they had once been joined. The ancient fern Glossopteris, found not only in Africa and South America, but also in India, Australia and Antarctica, is evidence that they were in ancient times a great southern supercontinent, Gondwana.
His work was met with disbelief from the geological profession. They did not see how these huge masses of rock could plough across the ocean floor. But from the 1950s, a new generation of brilliant scientists, including Harry Hess from Princeton, Toronto's Tuzo Wilson and my old professor Dan McKenzie from Cambridge University, took up Wegener's concept.
They used new magnetic data and ocean floor surveys to develop it into the theory of plate tectonics, with the Earth's crust divided into seven or eight major plates and many minor ones. This comprehensively explains the main features of the Earth's surface: mountain belts, ocean trenches, volcanoes and earthquakes, the distribution of fossils and the location of oil and gasfields.
Even today, plate tectonics continues to offer new clues for oil companies. The UK's Tullow, which struck oil in little-explored Ghana, then thought to look across the Atlantic to South America, from which Africa separated around 100 million years ago. Tullow was at once rewarded by a major find in French Guiana in September last year.
The geography works in reverse too. After the massive "pre-salt" oil discoveries in Brazil, it was natural to wonder if West Africa also had potential beneath two kilometres of sea and five kilometres of rock and shifting salt layers. Denmark's Maersk was the first to succeed, striking oil in pre-salt rocks in Angola in January; the US mid-cap Cobalt followed in February. Now, Total, BP, Statoil, ENI, Repsol and ConocoPhillips are looking in the same place.
And it is plate tectonics that created the Middle East's extraordinary petroleum wealth. For much of geological time, the region was covered by a shallow subtropical sea in which the remains of countless tiny plants and animals piled up. When Arabia and the Zagros region, part of the same plate, ran into central Iran, this organic matter was cooked into oil and gas, which accumulated in the massive geological folds forced up by the collision.
A better understanding of the Middle East's plate tectonics is hampered by regional suspicions and lack of freely available data. In particular, modern work in Iran and Iraq has been difficult because of lack of access. Saudi Arabia, Qatar, Kuwait and Bahrain are not even involved in the One Geology initiative, a scheme to unify the world's geological maps.
Nevertheless, in this region as elsewhere, Wegener's century-old insight continues to be the foundation of petroleum geologists' work. Oil is found, first of all, in the mind, and there are many new frontiers yet to discover.
Robin Mills is the head of consulting at Manaar Energy, and author of The Myth of the Oil Crisis and Capturing Carbon
Published: December 18, 2012 04:00 AM