Eye of the Sahara: A Colossal Eye in the Sahara Desert

This is the Richat Structure in northwestern Mauritania, otherwise known as the “Eye of the Sahara.

The Eye of the Sahara, also known as the Richat Structure or Guelb Er Richat, is a colossal geological marvel situated in the heart of the Sahara Desert, characterized by its striking resemblance to a bull’s eye pattern. This awe-inspiring formation, known as the Eye of the Sahara, the Richat Structure, or Guelb Er Richat, encompasses a vast expanse of approximately 40 kilometers within the borders of Mauritania and has remained largely undiscovered for centuries, known only to a select few local nomadic tribes.

In the 1960s, the Eye of the Sahara received its first visual documentation when Gemini astronauts utilized it as a reliable reference point to monitor the progress of their landing stages. These astronauts took pictures of the distinct formation from space out of scientific curiosity. Subsequently, the Landsat satellite contributed to the exploration of this remarkable geological structure by capturing additional images, thereby furnishing crucial data pertaining to its dimensions, elevation, and overall extent.

Key Takeaways: The Eye of the Sahara (Richat Structure)

  • The Eye of the Sahara, also known as the Richat Structure, is a stunning and unique geological formation located in Mauritania, West Africa.
  • It is a massive circular feature, around 50 kilometers in diameter, resembling a bullseye or “eye” when viewed from above.
  • The Eye of the Sahara was initially thought to be an impact crater, but it is now recognized as an eroded dome-shaped structure, likely formed by uplift and subsequent erosion over millions of years.
  • The distinct appearance of the Eye of the Sahara has made it a recognizable landmark for astronauts in space.

The Impressive Nature of the Eye of the Sahara

The Eye of the Sahara or Richat Structure photographed from the International Space Station.
Richat Structure photographed from the International Space Station. Image: NASA.

Geologists have extensively investigated the Eye of the Sahara and have come to the definitive conclusion that it represents a geological dome. Within this remarkable formation lie rocks that have withstood the test of time for an astonishing 100 million years or more, predating the emergence of life on our planet. Among these rocks are both igneous, arising from volcanic activity, and sedimentary layers, consisting of wind-blown dust and water-borne deposits.

Presently, the Eye of the Sahara boasts a diverse array of volcanic rock types, including kimberlite, carbonatites, black basalts akin to those observed on the Big Island of Hawaii, and rheolites.

Millions of years ago, the region surrounding the Eye of the Sahara experienced vigorous volcanic processes that emanated from the depths of the Earth’s interior. Contrary to the arid desert landscape we see today, these regions were considerably more temperate, with abundant flowing water. During that era, sandstone rocks with distinct layers were gradually deposited at the bottom of rivers and lakes, facilitated by prevailing winds. As time progressed, underground volcanic activity exerted pressure, lifting the upper layers of sandstone and other rocks.

Upon the cessation of volcanism, the dome-shaped rock layers became susceptible to the relentless forces of wind and water erosion. Consequently, the region began a gradual subsidence and inward collapse, leading to the formation of the strikingly circular “eye” structure that we marvel at today, the Eye of the Sahara.

Origins of the Eye of the Sahara

"Eye of the Sahara" in Northwest Africa
NASA Earth Observatory
“Eye of the Sahara” in Northwest Africa. Image: NASA Earth Observatory.

Through meticulous examination of ancient rocks within the Eye of the Sahara, researchers have successfully retraced the origins of this geological wonder. Their investigations suggest that the earliest formation of the Eye can be linked to the period when the supercontinent Pangea initiated its fragmentation. As Pangea underwent the process of breaking apart, the waters of the Atlantic Ocean began to encroach upon the region.

The geological processes responsible for the creation of the Eye began with the ascent of magma from the Earth’s mantle as Pangaea gradually disintegrated. This upward movement of molten material culminated in the formation of a circular sandstone dome. Subsequently, the forces of erosion began to act upon both the igneous rocks and the sandstone, shaping the structure further.

As time progressed, the circular dome underwent a process of subsidence, resulting in the formation of prominent ridges. These ridges contributed to the current submerged, circular shape known as the Richat Structure. Presently, the Eye is observed to be slightly sunken in comparison to the surrounding terrain, adding to its unique and captivating appearance.

The End of the Eye of the Sahara

The Eye of the Sahara holds a magnetic appeal, attracting both tourists and geologists who are drawn to its captivating geological features. Visitors flock to this unique site to study and marvel at its intriguing formations. Fortunately, the location’s remote and sparsely populated surroundings, coupled with minimal rainfall, protect it from the immediate dangers of human destruction.

However, despite its current resilience, the future of the Eye remains subject to the inexorable forces of nature. If left unchecked, the effects of ongoing erosion could potentially lead to the gradual deconstruction of this magnificent spectacle. Additionally, the impact of climate change, which contributes to increased desertification in the region, may result in heightened sand accumulation from wind-blown particles. In the distant future, this scenario could potentially lead to the filling of the Eye of the Sahara with sand and dust, altering its distinctive appearance.

Regrettably, if such a future unfolds, visitors arriving at the site in subsequent generations may find no trace of what was once one of Earth’s most striking geological structures, underscoring the transient nature of our planet’s most remarkable features. It emphasizes the importance of preserving and understanding these natural wonders while they still exist in their full splendor.

The Eye of the Sahara (Richat Structure) at a Glance


What other names is the Eye of the Sahara known by?

Besides the Eye of the Sahara and the Richat Structure, this geological formation is also referred to as the Eye of Africa due to its location in the African continent.

Was the Eye of the Sahara ever considered to be an impact crater?

Yes, initially, the Eye of the Sahara was thought to be an impact crater created by a meteorite strike. However, further geological studies ruled out this hypothesis and suggested alternative mechanisms for its formation.

Can tourists visit the Eye of the Sahara?

Yes, tourists can visit the Eye of the Sahara and explore its unique geological formations. However, being located in a remote and arid region, it may require careful planning and guided tours for a safe and fulfilling visit.

Are there any scientific research efforts in the Eye of the Sahara?

Yes, the Eye of the Sahara continues to attract scientific researchers from various fields, including geology and earth sciences. Studies and research on the geological history and processes of this landmark contribute to our understanding of similar structures on Earth and other planets.

Is the Eye of the Sahara visible from space?

Yes, the Eye of the Sahara is easily visible from space due to its distinct circular shape and large size. Astronauts onboard the International Space Station have captured images of this unique geological feature.