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Richat Structure
Jan 29, 2026 9:17 PM

  Richat Structure geographic feature, Mauritania Ask the Chatbot a Question Ask the Chatbot a Question Also known as: Eye of Africa, Eye of the Sahara, Guelb er Richât Written by Frannie Comstock Frannie Comstock is a writer based in Chicago. Frannie Comstock Fact-checked by The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors. The Editors of Encyclopaedia Britannica Last Updated: Nov 22, 2024 • Article History Table of Contents Table of Contents Ask the Chatbot a Question Arabic: Guelb er Richât (Show more) Also called: Eye of the Sahara or Eye of Africa (Show more) { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type" : "Question", "name" : " What is the Richat Structure? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "The Richat Structure is a large geographic feature with concentric rings located in the Sahara near Ouadane, Mauritania. It is an uplifted geological dome formed by molten rock during the Cretaceous Period." } } , { "@type" : "Question", "name" : " Why was the Richat Structure initially thought to be an impact crater? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "It was initially thought to be an impact crater because of its raised outer perimeter and sunken center, but it lacks key features of impact craters, such as a central peak and evidence of molten rock from impact heat." } } , { "@type" : "Question", "name" : " How old is the Richat Structure? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "Geologists agree that the Richat Structure is at least 100 million years old." } } ] } Top Questions What is the Richat Structure? The Richat Structure is a large geographic feature with concentric rings located in the Sahara near Ouadane, Mauritania. It is an uplifted geological dome formed by molten rock during the Cretaceous Period.

  Why was the Richat Structure initially thought to be an impact crater? It was initially thought to be an impact crater because of its raised outer perimeter and sunken center, but it lacks key features of impact craters, such as a central peak and evidence of molten rock from impact heat.

  How old is the Richat Structure? Geologists agree that the Richat Structure is at least 100 million years old.

  Richat Structure, large geographic feature with a diameter of about 50 km (30 miles), consisting of a series of concentric rings located in the Sahara near the town of Ouadane, Mauritania. Named for a Berber term for “feather,” the Richat Structure was originally thought to be an impact crater because of its raised outer perimeter and sunken center. However, the structure lacks key features of impact craters, such as a central peak and evidence of molten rock from the heat of impact. It has since been determined to be an uplifted geological dome, or domed anticline, originally formed by molten ...(100 of 567 words)

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