Chert sedimentary environment

Bass and Mescal Limestone should not have been similarly depleted by this mechanism. Second, an evaporitic depositional environment would result in compensating trends of 0-enriched water and anomalously high local temperature that might effectively cancel each other. For example, the cherts from Lake Magadi, which have OsMow values ranging up to +44%c, are among the most 0-enriched of all terrestrial sedimentary rocks even though they formed in an evaporitic environment (O Neil and Hay, 1973). 

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