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

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Beautifully shaped gneiss in Massaschluct (Route 1 in the Valais Alps)

Canyon formation

Although plate tectonics are responsible for the formation of the Alps and the distribution of its rock types, the rugged landscape seen today is largely due to glaciation. Over the last two million years there have been a number of periods of glacial advance and retreat that have done much to remodel the region. The last glacial period ended some 10,000 years ago, when the climate changed so quickly that the glaciers retreated into the mountains over only a few hundred years – a mere blink of an eye in geological terms. Colossal sheets of ice were set in motion across the mountains, scouring deep channels into the rock and forming conduits for billions of tons of melt-water – the canyons we see today.

Limestone environments are susceptible to another, more subtle process – karstification. Limestone is one of the few rocks soluble in rainwater (a weak acid), and it gradually dissolves over time to form a number of characteristic landforms, including caves, dissected plateaus and deep slot canyons.