The isolated Cape Verde islands, 570 kilometres off the West African coast are a series of volcanic islands thought to have formed over a “hot spot” in the Earth’s mantle.
This archipelago of ten islands and eight smaller islets sits in a horseshoe formation in the Atlantic Ocean, with the islands divided into two groups: the Ilhas de Barlavento (“windward” islands) to the north and the Ilhas de Sotavento (“leeward” islands) to the south.
Three of the islands are fairly flat, sandy and arid but the majority of the landmasses, including the principle island of Santiago, are rugged and rocky, indicating their volcanic origins.
The Cape Verde islands are believed to have formed over a volcanic “hot spot”: an area on the Earth’s surface where molten magma from deep within the Earth rises up through the crust.
These plumes of hot material create isolated volcanoes on the surface of the Earth, which do not have to appear over a plate boundary; this helps to explain the isolated location of the
islands, away from any other chains of volcanoes or landmasses.
Magnetic anomalies studied by geophysicists around the archipelago suggest that the island structures are approximately 150 million years old, which is very young in geological terms, and the current islands date from eruptions occurring just eight to 20 million years ago.
Evidence of these eruptions can be clearly seen across the islands with volcanic peaks and rock dominating the landscape.
The beautiful pillow lavas found along the coast of Maio are an excellent example: these marshmallow-shaped formations are created by molten lava erupting into the sea and rapidly cooling in the water.
The largest and most active volcano in the region is Pico, found on the island of Fogo, named by Portuguese settlers after its fiery eruptions.
It has a prominent eight kilometre wide caldera and rises 2,829 metres above sea level, with its last major eruption in 1995 which caused the widespread evacuation of the island.