Mid-Atlantic Ridge

At Thingvellir, the North American plate is moving away from the European plate at an annual rate of 2 cm/0.8 in. Thingvellir marks the position of the Mid-Atlantic Ridge, a constructive plate boundary where new material is formed by the cooling of lava. There are steep-sided rift valleys, and a broad flat plain in the centre of the rift valley.

A steep rift-valley wall at Thingvellir, Iceland. Rift valleys are created when tectonic plates pull apart, and part of the Earth's crust subsides. The Mid-Atlantic Ridge can be seen in action here at Thingvellir, where the North American plate is pulling away from the European plate.

Rocks at Thingvellir, in Iceland, are disrupted by earth movements as two plates of the Earth's crust move apart, as well as broken down by repeated freeze-thaw action.

A river runs through a steep-sided rift valley. This valley was formed as a result of the movement of tectonic plates on the Mid-Atlantic Ridge at Thingvellir, Iceland.

The steep inclines on these massive slabs of rock at Thingvellir, Iceland, testify to the tectonic forces at work here. This is the site of part of the Mid-Atlantic Ridge, where the North American plate is pulling away from the European plate. This is a constructive plate boundary, where new material is formed by the cooling of lava, but it also leads to the subsidence of some of the Earth's crust.

A plain in southern Iceland covered with the remains of former lava flows. The Reykjanes peninsula has many lava flows, as well as geothermal fields and crater lakes. Tectonically active, Iceland is located on a mid-ocean ridge where the North American and European plates move apart.

Mid-ocean ridge that runs along the centre of the Atlantic Ocean, parallel to its edges, for some 14,000 km/8,800 mi - almost from the Arctic to the Antarctic. Like other ocean ridges, the Mid-Atlantic Ridge is essentially a linear, segmented volcano.

The Mid-Atlantic Ridge runs down the centre of the ocean because the ocean crust has continually grown outwards from the ridge at a steady rate during the past 200 million years. Iceland straddles the ridge and was formed by volcanic outpourings.