Chert nodules (black) in chalk, formed by concretionary enrichment of silica after the chalk has been deposited in marine environments. Cretaceous for

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Chert nodules (black) in chalk, formed by concretionary enrichment of silica after the chalk has been deposited in marine environments. Cretaceous formation of the Avedat, Negev desert, Israel.

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Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: avedat, chalk, chert, concretionary, cretaceous, desert, enrichment, environment, formation, formed, geological, geology, israel, marine, mineral, nature, negev, nodule, nodules, rock, silica