40 million years – 40 meters
Alps. (M. Klüber / Wikimedia Commons)
The Alps rise as Africa collides with Europe. The main groups of mammals and over half of the current orders of birds exist.
Image: The Alps. M. Klüber | Wikimedia
The main uplifting phase of the Alps occurred at this time. The Alps belong into a long mountain chain that runs from the Pyrenees in the west, all the way to the Himalayas in the east. The formation process of this long mountain chain started already much earlier, at about 300 million years ago, as the continents were starting to move apart from the Pangaean supercontinent. At that time, or even earlier, the Tethys ocean had formed in between the Laurasian and Godvana continents. As the continents moved in respect to each other, this old ocean was closed, and gradually disappears, as the African plate was moving towards north, and pushing over the Eurasian plate. The old bottom sediments of the Tethys ocean were push up in front of the continental movement, and nowadays they occur high upon the mountain slopes. For instance the Matterhorn mountain, the landmark of the Alps, is formed in a layered fashion such that its top is formed of the African plate, the mid slopes contain the metamorphosed bottom sediments of the old Tathys ocean, with their sea-bottom fossils, and the base of the mountain is formed of the European plate. The surface of the upper crust of the Southern Apulian plate was thrusted over the European crust, and became the later Austroalpine nappes. The high pressure of the continental movement caused decollement of the thrusting mountain areas, which later become to be the Helvetic nappes. The formation of the Alpean Mountains still continues, and is manifested in form of frequent earthquakes in the area.
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