Which term best describes sediment composed of the calcareous shells of marine microorganisms such as foraminifera?

Which term best describes sediment composed of the calcareous shells of marine microorganisms such as foraminifera?

• A. Coccolithophore
• B. Foraminiferan
• C. Diatom
• D. Evaporite

Answer: (B)

Calcareous ooze forms when calcium carbonate shells from marine microorganisms accumulate on the seafloor. Foraminifera are one such group that build calcium carbonate tests, and their shells collecting as sediment is described as foraminiferan sediment. Among the options, this is the best fit because diatoms yield siliceous shells and would form diatomaceous ooze, coccolithophores form coccoliths that create coccolith ooze, and evaporites are chemical precipitates, not shell-based sediment. So the sediment composed of these calcareous shells is best described as foraminiferan (foraminiferal) sediment.

Calcareous ooze forms when calcium carbonate shells from marine microorganisms accumulate on the seafloor. Foraminifera are one such group that build calcium carbonate tests, and their shells collecting as sediment is described as foraminiferan sediment. Among the options, this is the best fit because diatoms yield siliceous shells and would form diatomaceous ooze, coccolithophores form coccoliths that create coccolith ooze, and evaporites are chemical precipitates, not shell-based sediment. So the sediment composed of these calcareous shells is best described as foraminiferan (foraminiferal) sediment.