Читать книгу Canyoning in the Alps. Graded routes in Northern Italy and Ticino, Austria, Slovenia and the Valais Alps онлайн

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Geology of the Alps (for canyoners)

A brief history of the Alps

The Alps, like all great mountain ranges, were created by the collision of continents. They began rising some 90 million yeas ago as Italy, inching slowly northwards, collided with the southern edge of mainland Europe. The ocean floor that once divided the two continents gradually disappeared, driven into the Earth’s mantle as the gap between them closed. As the land masses collided, their margins buckled, folded and slid over each other to form immense overlapping thrust sheets, or nappes, which pushed northwards as Italy continued to advance. In this way, great rock masses from the Italian plate were displaced far to the north to create mountains in what are now Switzerland, Austria and France. As the Alps rose, the rocks of the ancient seabed were exhumed, now metamorphosised by the immense heat and pressure of the Earth’s interior. Today these hard-wearing metamorphic rocks (the so-called Penninic nappes) form much of the backbone of the Western Alps.