Elk River Formation

{{Short description|Geologic formation in Oregon, United States}}

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| name = Elk River Formation

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| type = Formation

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| region = Oregon

| country = United States

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| overlies =Port Orford Formation

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The Elk River Formation is a geologic formation in Oregon. It preserves fossils.{{Citation needed|date=June 2024}} It consists of terrace deposits overlying the Port Orford Formation.{{Cite web |title=USGS Geologic Names Committee Archives: Port Orford Formation |url=https://ngmdb.usgs.gov/Geolex/stratres/cards?q=PortOrfordFormation |website=National Geologic Map Database |publisher=United States Geologic Survey}}