Three Forks Shale

{{Short description|Geologic formation in Montana and North Dakota, United States}}

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| name = Three Forks Shale

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| type = Formation

| age = Devonian

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| region = Montana

| country = United States

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The Three Forks Shale is a geologic formation in Montana and North Dakota. It preserves fossils dating back to the Devonian period.{{cite web|title= Fossilworks: Gateway to the Paleobiology Database|author= ((Various Contributors to the Paleobiology Database))|url= https://www.fossilworks.org|access-date= 17 December 2021}}