As a young man, Charles Darwin found the fossil of a marine animal far inland. If it were true that marine animals had once lived in this place, then the existing theories of the earth’s history were wrong. Darwin showed his find excitedly to an eminent geologist, who replied: “Oh, let’s hope it’s not true.” The geologist preferred to believe that someone had dropped the fossil there, after a trip to the seaside! From the standpoint of common sense, it appears incredible that continents should move. Our eyes tell us that this is not so. The average velocity for that kind of movement is around 1-2 centimetres a year. Therefore, for normal purposes it may be discounted. However, over a much longer period of millions of years, these slight changes produce the most dramatic changes imaginable.

On the top of the Himalayas (almost 9,000 metres above sea level) there are rocks which contain fossils from marine organisms. This means that these rocks, which originated at the bottom of a prehistoric sea, the Tethys Ocean, were thrust upwards over a period of 200 million years to create the highest mountains in the world. Even this process was not a uniform one, but involved contradictions, with tremendous upheavals, advances and retreats, through thousands of earthquakes, massive destruction, breaks in continuity, deformations and folds. It is evident that the movement of the plates is caused by gigantic forces inside the earth. The entire make-up of the planet, its appearance and identity is determined by this. Humanity has direct experience of only a tiny fraction of these forces through earthquakes and volcanic eruptions. One of the basic features of the earth’s surface is the mountain ranges. How do these develop?

Take a bunch of paper sheets and press it against a wall. The sheets will fold and deform under the pressure and they will “move” upwards, creating a curved feature. Now imagine the same process when an ocean is being pressurised between two continents. The ocean is being forced under one of the continents, but the rocks at that point will be deformed and fold, creating a mountain. After the total disappearance of the ocean, the two continents will collide, and the crust at that point will be thickened vertically as the continental masses are compressed. The resistance to subduction causes large nappe folds and thrust faults, and this uplift gives rise to a mountain chain. The collision between the Euro-Asian and the African plates (or parts of Africa) created a long mountain chain, starting from the Pyrenees in the West, passing through the Alps (collision of Italy and Europe), the Balkans, Hellenic, Tauridic, Caucasus (collision of South Arabia and Asia) and finally the Himalayas (collision of India–which was originally an island–and Asia). In the same manner, the Andes and Rocky mountains in America are located over the zone where the Pacific Ocean plate is dipping under the American continent.

It is not surprising that these zones are also characterised by intense seismic activity. The world’s seismically active zones are exactly the borders between the different tectonic plates. In particular, zones where mountains are being created signify areas where colossal forces have been accumulated over a long time. When continents collide, we see the accumulation of forces acting on different rocks, at different locations and in different ways. Those rocks, which are composed of the hardest material, resist deformation. But, at a critical point, quantity is transformed into quality, and even the hardest rocks are broken or plastically deformed. This qualitative leap is expressed in earthquakes, which despite the spectacular appearance actually represent only a tiny movement of the earth’s crust. The formation of a mountain chain requires thousands of earthquakes, leading to extensive folding, deformation and the movement upwards of rock.

Here we have the dialectical process of evolution through leaps and contradictions. The rocks, which are being compressed, present an initial barrier, offering resistance to the pressure of subterranean forces. However, when they are broken, they turn into their exact opposite, becoming channels for the release of these forces. The forces that operate under the surface are responsible for creating mountain chains and ocean trenches. But on the surface there are other forces operating in the opposite direction.

Mountains do not continuously rise higher and higher, because they are subject to opposing forces. On the surface we have weathering, erosion and transportation of matter from the mountains and the continents back to the oceans. Solid rocks are worn away by the action of strong winds, intense rain, snow and ice, which weaken and fracture the outer shell of the rocks. After a period, there is a further qualitative leap. The rocks gradually lose their consistency, small grains begin to separate from them. The effect of wind and water, especially rivers, transport millions of grains from higher levels to basins, lakes, but mainly oceans, where these rock-particles are gathered together again at the bottom of the sea. There they are buried again, as more and more material is accumulating above them and a new operation appears, the opposite one – rocks are being consolidated again. As a result, new rocks are created, which will follow the movement of the ocean bed until they are once again buried under a continent, where they will melt, possibly emerging once again at the top of a new mountain somewhere in the earth’s surface.