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Stromatolites are layered structures formed primarily by... | QuestionStock

Representative image for question: Stromatolites are layered structures formed primarily by which organisms that trap sediment and precipitate minerals?

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Nature

Stromatolites are layered structures formed primarily by which organisms that trap sediment and precipitate minerals?

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Stromatolites are layered structures formed primarily by which organisms that trap sediment and precipitate minerals?

Options:

Cyanobacteria
Diatoms
Foraminifera
Fungi

Correct answer: Cyanobacteria

Explanation: Stromatolites are built by cyanobacteria that trap sediment and precipitate calcium carbonate; fossil stromatolites occur in rocks older than 3.5 billion years, recording some of Earth's earliest life.

Created 2026-03-10T17:16:16.194Z. Updated 2026-03-10T17:16:16.194Z.