The Richat Structure Anomalies

The Richat Structure, known locally as Guelb er Richât and to a generation of astronauts as the Eye of the Sahara, is a near-perfect concentric formation roughly fifty kilometres in diameter on the Adrar Plateau of central Mauritania. Its origins are now reasonably well understood, the consensus interpretation being a deeply eroded uplifted dome rather than an impact crater, but the surrounding terrain has accumulated a substantial body of folkloric and contemporary anomaly reports that mainstream geology cannot fully account for.

Historical Context

The structure entered Western awareness only in 1965, when astronauts aboard the Gemini IV mission photographed it from orbit and asked geologists at Houston to identify the strange bullseye on the desert floor. To the Reguibat and Imraguen peoples of the surrounding region, however, the formation had been known for centuries as a place of baraka, a difficult Arabic concept that combines blessing, danger and supernatural charge. Caravans on the salt routes from Ouadane traditionally avoided the centre of the structure, and oral tradition collected by the French colonial geologist Théodore Monod in the 1930s and 1940s described unaccountable silences, periods during which water in animal-skin bags would unaccountably warm or cool, and infrequent appearances of what guides called the lights.

Monod, one of the most respected Saharan field scientists of the twentieth century, was sufficiently struck by the consistency of these accounts that he devoted several pages of his 1958 Méharées to them, recording them as ethnographic data without paranormal commitment.

Witness Account

The most widely cited modern report belongs to a French geologist, Bertrand Fouché, who led a small uranium prospecting expedition to the inner ring of the structure in 1973. Fouché’s field notes, later excerpted in the journal Sciences et Avenir, describe an evening at the central plateau during which all four members of the team independently noticed a sudden cessation of the desert’s normal sounds. The wind dropped, the camp’s transistor radio fell to static, and a magnetic compass on the geological table began to rotate slowly through more than ninety degrees over the course of perhaps thirty seconds before settling at a new orientation roughly forty degrees off true. Two members of the team reported a brief greenish glow above the eastern ridge of the inner ring. The phenomenon, whatever it was, lasted no more than three minutes.

Subsequent expeditions have reported smaller-scale anomalies. In 1998 a National Geographic survey team documented persistent compass deviation at three locations near the central feature, attributing it provisionally to localised concentrations of magnetite-rich igneous intrusions. A 2014 expedition led by the French archaeologist Robert Vernet recorded brief radio interference at the same locations and noted that local guides continued to refuse to camp inside the inner ring overnight.

Investigation

The geological case for the structure being an eroded igneous dome is strong, and recent satellite gravity surveys have largely settled the question of its origin. The persistence of anomaly reports at the site is therefore unusually interesting, because it cannot be parsimoniously absorbed into the impact-crater speculation that briefly fashionable in the late 1960s and early 1970s. Instead, the reports cluster around three specific phenomena: magnetic deviation, sudden acoustic stillness, and infrequent glowing lights observed at low elevation above the inner rings.

Magnetic deviation is geologically credible given the structure’s mineralogy. The acoustic and luminous phenomena are harder to characterise. A 2011 paper in Geophysical Research Letters on dust devils and electrostatic discharge in the Sahara offered a possible mechanism for the lights, suggesting that triboelectric charging of dust columns in the structure’s distinctive bowl topography could generate brief corona effects. The same paper offered no explanation for the reported silences, which several witnesses describe as feeling subjectively pressure-like, as though the air itself had thickened.

Cultural Impact

In Mauritanian tradition the centre of the Richat Structure remains a place to be approached with care. Local guides accompanying foreign expeditions will often perform a brief recitation of protective verses upon entering the inner ring, and some refuse outright to overnight there. The site has attracted increasing attention from speculative writers since the publication of Jimmy Bright’s 2010 article identifying the structure as a candidate location for Plato’s Atlantis, a claim that no professional archaeologist takes seriously but which has driven a small wave of tourism to the area.

The Richat reports sit alongside other Saharan anomaly traditions including the door to hell at Darvaza in Turkmenistan, and they share a common atmospheric quality with the desert lights described in the Empty Quarter of Saudi Arabia. Whether one regards the phenomena as geophysical, perceptual or paranormal, the Eye of the Sahara has accumulated more than half a century of consistent strange-experience reporting, and continues to do so.

Sources

• Monod, Théodore. Méharées: Explorations au vrai Sahara. Editions Je Sers, 1958.
• Fouché, Bertrand. “Une nuit au cœur du Richat.” Sciences et Avenir, July 1974.
• Vernet, Robert. La Mauritanie: archéologie et préhistoire. Sépia, 2007.
• Matsui, T. et al. “Triboelectric phenomena in Saharan dust columns.” Geophysical Research Letters 38 (2011).