Geography and Geology of Cape Verde

The Cape Verde Islands are volcanic in origin, having been formed by the accumulation of rocks resulting from eruptions on submarine platforms. These rocks rose from a depth of approximately 3000 meters from the seabed, from a large topographic elevation called the Cape Verde Ridge.

Volcanic activity in the archipelago is the result of a hotspotThis is a region of the earth's mantle where columns of hot magma rise through the earth's crust and erupt at the bottom of the sea.

Cape Verde's geological resources

Cape Verde's geological resources mainly include basic rocks with a predominance of basaltic rocks, phonotrachytic rocks and pyroclastic products (bombs, lapilli, sands and tuffs). 

Sedimentary rocks are found throughout the archipelago (sand, alluvium, beach gravels, flood deposits and slope deposits), with a greater incidence on the island of Maio, where clays, marls, Jurassic and Cretaceous limestones appear. It should be noted that the percentage of sedimentary rocks is higher than that of magmatic rocks on the island of Maio, unlike the others.

Cape Verde's soils are generally shallow, poor in organic matter, poorly differentiated and rocky. Their substrate is volcanic rock (80% basalt) and sedimentary rock.

Only 10% of the territory's land is potentially arable/cultivable (around 40,000 ha). This is one of the country's main vulnerabilities, since most of what is consumed is imported.

Topography and relief of the Cape Verde islands

Despite their common volcanic origin, the islands of Cape Verde vary in terms of relief and topography. In topographical terms, the islands can be divided into two groups:

• Flat islands: made up of a group of islands of gentle relief, with only a few scattered low peaks; this group includes the islands of Maio, Boa Vista, Sal and Santa Luzia.
• Mountainous islands: characterized by steep and rugged terrain, often with impressive cliffs, gorges and steep slopes.

This group includes the islands of Santo Antão, São Nicolau, Santiago, Fogo and Brava.

The island of São Vicente occupies an intermediate position between these two groups, both in terms of topography and relief.

With the exception of the flatter islands (Santa Luzia, Sal, Boavista and Maio), the relief of the archipelago is considerably rugged. The landscapes vary greatly between the islands, from mile-long beaches (such as Santa Mónica beach on the island of Boavista) to extensive salt pans (on the islands of Sal and Maio), stunning cliffs (mainly on Santo Antão, São Nicolau and Brava) and even an active volcano on the island of Fogo.

Cape Verde's highest points

The following table summarizes the highest points in Cape Verde, their location and respective altitudes.

O Cape Verde's highest point is Pico do Fogowith an altitude of 2829 meters above sea level.

Age of the Cape Verde Islands

Although there is little consensus on the age of the islands, it is estimated that the islands of Sal, Maio and Boavista are the oldest. As a result of strong wind erosion over time, these islands are very sandy and flat.

On the other hand, the islands with a more "wrinkled" and rocky appearance are more recent, with the islands of Fogo and Brava estimated to be the youngest in the archipelago.

The following figure illustrates the approximate age of the Cape Verde islands.

Volcanic activity in Cape Verde

Despite the volcanic origin and some latent volcanic activity throughout the archipelago, it is mostly unnoticeable. The last volcanic eruption in the country occurred in 2014, with no human losses.

Generally, between the premonitory signs of volcanic activity and the explosion of magma to the surface, weeks to months can pass, allowing protective actions to be taken.

Cape Verde's National Institute of Meteorology and Geophysics has 18 seismometric stations distributed throughout the archipelago, which monitor any volcanic activity on the islands. The island of Fogo also has three inclinometer stations that make it possible to monitor the deformation of the ground produced by magmatic intrusions, as a complementary way of monitoring the Fogo volcano. These measures aim to ensure that safety measures are taken in good time in the event of significant volcanic activity.

Conclusion

Cape Verde has a remarkable geological diversity, with impressive landscapes ranging from steep mountains to white sandy beaches and crystal clear waters. This diversity offers great adventure options throughout the islands.

If you are interested in learning more about the topic or would like help exploring the best that Cape Verde has to offer, please contact us.