Tenerife is an island created volcanically, building up from the ocean floor 20-50 million years ago
According to the Theory of Plate Tectonics, the ascent of magma originating from the Earth's mantle is produced by the effects of tectonic activity from faults or fractures that exist at the oceanic plate. These fractures lie along the structural axes of the island itself, forming themselves from the Alpine orogeny during the Tertiary Period due to the movements of the African plate.
Underwater fissural eruptions originated from the pillow lava, which are produced by the rapid cooling of the magma when it comes in contact with water, obtaining their peculiar shape. This pillow-lava accumulated, constructing the base of the island underneath the sea. As this accumulation approached the surface of the water, gases erupted from the magma due to the reduction of the surrounding pressure. The volcanic eruptions became more violent and had a more explosive character, and resulted in the forming of peculiar geological fragments.
