I shall leave Brexit aside today. I’ve had quite enough of it.
For the past year or so I’ve been thinking about ice ages, using the very simple idea that sheets of ice and snow act as thermal insulation on the surface of the Earth, causing it to warm, and to then melt the overlying ice.
It’s an idea that is a little akin to the theory of Plate Tectonics, which is that the continents on the surface of the Earth act like the foam on top of a stirred cup of cappuccino coffee, parting and merging as they move on the currents beneath them.
In school Geography lessons in the early 1960s we were not taught this theory, largely because it only became current in the late 1960s. It was a very new idea. And as soon as I heard of it I became an instant believer.
Why? Because it was a Big Idea, an all-embracing, captivating idea, and also a very simple idea. All you needed to understand Plate Tectonics was a cappuccino coffee and a spoon, and you’ll soon be seeing Africa and America and Australia moving round and round, with black coffee oceans opening up and closing between the whirling foam continents.
And it seems that it was such a simple and plausible and obvious idea that it completely captured Geology in the space of a couple of decades. It was Wegener’s 1920 idea of continental drift, but with the continents now being powered by convection currents deep inside the mantle of the Earth. Plate Tectonics seems to have swept Geology like Hernán Cortés swept the Aztec Empire in the two years between 1519 and 1521. It seems to have prefigured the very similar capture of Climatology by the Global Warmers and their invincible carbon dioxide a couple of decades later.
Were there any Plate Tectonic sceptics? Did everyone become true believers in Plate Tectonics?
It seems that the Russians in the Soviet Union were deeply sceptical about the theory of Plate Tectonics (and maybe many still are). But it seems that elsewhere there slowly emerged an organised opposition to Plate Tectonics:
…in the 1950s and 60s the new theory of Plate Tectonics was propounded
by “Geophysicists” (Physicists) and mainly young Geologists with little experience, depth of understanding or respect for existing geology. The theory, although admittedly simplistic and with little factual basis but claiming to be all embracing, was pursued by its proponents in an aggressive, intolerant, dogmatic and sometimes unfortunately an unscrupulous fashion. Most geologists with knowledge based locally or regionally were not confident in dealing with a new global theory which swept the world and was attractive in giving Geology a prestige not equalled since the nineteenth century.
So Plate Tectonics was the invasion of Geology by the all-conquering army of Physics. The geologists, with their little hammers and collections of rock samples, had about as much hope of defeating the Geophysicists as the Aztecs had of defeating Cortés.
All these new Big Ideas always seem to be “aggressive, intolerant, dogmatic and unscrupulous.” The doctrine that Smoking Causes Lung Cancer was another aggressive, intolerant, dogmatic, and unscrupulous idea that began to sweep the world in the 1950s. And Global Warming is another aggressive, intolerant, dogmatic, and unscrupulous idea that gained currency in the 1990s. And it seems that the proponents of Plate Tectonics in the 1960s were just as nasty.
The geological resistance movement to Plate Tectonics, which seems to have gradually mounted over the decades subsequent to the 1960s, now seems to find its expression in New Concepts In Global Tectonics, which has been publishing papers and journals since about 1998, all critical of Plate Tectonics in one way or other.
Some of their criticisms include:
- Subduction: The volume of crust generated at ocean ridges is supposed to be equalled by the volume subducted. But the ocean ridge system is allegedly producing new crust along a total length of 2 x 74,000 km, whereas there are about 43,500 km of trenches and 9000 km of “collision zones” – or a third of the amount of “spreading centres”.
- Subduction: How ocean crust can be thrust down into the denser mantle has never been satisfactorily explained. An analysis of the mechanics of subduction suggests that it could probably never have started, let alone continued (James, 2000).
- Hotspots: Hotspots are commonly attributed to “mantle plumes” rising from the core-mantle boundary. Sheth (1999) showed that plume explanations are ad hoc, artificial, and inadequate, and that plumes are not required by any geological evidence. A mantle plume from a deep hotspot would broaden upward as a result of drag forces, and would attain a surface width of several hundred kilometres, far beyond oceanic island dimensions.
- India and Tethys *: There is overwhelming geological and palaeontological evidence that India has been an integral part of Asia since at least mid-Proterozoic time (Chatterjee and Hotton, 1986; Ahmad, 1990; Saxena et al., 1985; Saxena & Gupta, 1990; Meyerhoff et al., 1991). Yet on the basis of palaeomagnetic data and marine magnetic anomalies, plate tectonicists claim that India detached itself from Antarctica sometime during the Mesozoic, and then drifted northeastward up to 7500 km, at speeds of up to 18 cm/yr, until it finally collided with Asia in the Eocene (55 Ma), pushing up the Himalayas and the Tibetan Plateau.
I’m rather struck by the thought that, while we can apparently see 13.4 billion light years out into space (one light year = 9,460,730,500,000 kms), we can’t see further than 12.2 kilometres into the Earth beneath our feet. So our beliefs about the interior of the Earth, including the supposed convection currents within the mantle of the Earth, are all at best educated guesses, and at worst wild speculation. For nobody has been there and measured the temperatures, or brought back samples of mantle or core, like Cortés brought back the products of Mexico to Spain.