Renton Formation (Wikipedia)

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The Renton Formation is a geologic formation in Washington (state) within the Puget Group. It preserves fossils dating back to the Paleogene period.

Puget Group (Wikipedia) The Puget Group is a geologic group in Washington (state). It preserves fossils dating back to the Paleogene period. ¶ Two key formations include the Renton Formation and the Tukwila Formation.
Washington (state) (Wikipedia) Washington (/ˈwɒʃɪŋtən/), officially the State of Washington and often referred to as Washington state to distinguish it from the national capital, Washington, D.C., is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington Territory, which was ceded by the British Empire in 1846, by the Oregon Treaty in the settlement of the Oregon boundary dispute. The state is bordered on the west by the Pacific Ocean, Oregon to the south, Idaho to the east, and the Canadian province of British Columbia to the north. It was admitted to the Union as the 42nd state in 1889. Olympia is the state capital; the state’s largest city is Seattle.

Tukwila Formation (en.wikipedia.og) The Tukwila Formation is a geological formation in King County, Washington within the Puget Group. It is named after Tukwila area, which is close to the formation. The formation consists of various fossils of marine origin.