Umtanum Ridge is a long

anticline In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the ...

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and ...

ridge A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...

Yakima County Yakima County is a county in the U.S. state of Washington. As of the 2020 census, its population was 256,728. The county seat and largest city is Yakima. The county was formed out of Ferguson County in January 1865 and is named for the Yakama t ...

and

Kittitas County Kittitas County () is a county located in the U.S. state of Washington. At the 2020 census, its population was 44,337. Its county seat and largest city is Ellensburg. The county was created in November 1883 when it was carved out of Yakima Coun ...

in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on ...

. It runs for approximately 55 miles east-southeast from the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, ...

, through the

Yakima Training Center The Yakima Training Center (YTC) is a United States Army training center, used for maneuver training, Land Warrior system testing and as a live fire exercise area. It is located in the south central portion of the U.S. state of Washington, bounde ...

to the edge of the

Columbia River The Columbia River (Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, C ...

Priest Rapids Dam Priest Rapids Dam is a hydroelectric, concrete gravity dam; located on the Columbia River, between the Yakima Firing Range and the Hanford Nuclear Reservation, and bridges Yakima County and Grant County, in the U.S. state of Washington. The dam is ...

and

Hanford Reach The Hanford Reach is a free-flowing section of the Columbia River, around long, in eastern Washington state. It is named after a large northward bend in the river's otherwise southbound course. Hanford Reach is the only section of the Columbia i ...

. The eastern end of Umtanum Ridge enters

Hanford Reach National Monument The Hanford Reach National Monument is a national monument in the U.S. state of Washington. It was created in 2000, mostly from the former security buffer surrounding the Hanford Nuclear Reservation. The area has been untouched by development or ...

and the

Hanford Site The Hanford Site is a decommissioned nuclear production complex operated by the United States federal government on the Columbia River in Benton County in the U.S. state of Washington. The site has been known by many names, including SiteW a ...

. Umtanum Ridge is paralleled on the north by

Manastash Ridge Manastash Ridge is a long anticline mountain ridge located in central Washington state in the United States. Manastash Ridge runs mostly west-to-east in Kittitas and Yakima counties, for approximately 50 miles. The ridge is part of the Yakima Fol ...

and on the south by

Yakima Ridge Yakima Ridge is a long anticline mountain ridge in Yakima County and Benton County in the U.S. state of Washington. From its western end just north of the city of Yakima, the ridge runs east-southeast through the Yakima Training Center to its ea ...

. The

Yakima River The Yakima River is a tributary of the Columbia River in south central and eastern Washington state, named for the indigenous Yakama people. Lewis and Clark mention in their journals that the Chin-nâm pam (or the Lower Snake River Chamnapam Nat ...

cuts through the ridge at the Umtanum Ridge Water Gap. The name Umtanum comes from

Sahaptin The Sahaptin are a number of Native American tribes who speak dialects of the Sahaptin language. The Sahaptin tribes inhabited territory along the Columbia River and its tributaries in the Pacific Northwest region of the United States. Sahaptin-s ...

, probably /ɨmtanam/, possibly meaning "taste" or "mouth full", from the root /ɨm/, "mouth". Umtanum Ridge is part of the

Yakima Fold Belt The Yakima Fold Belt of south-central Washington, also called the Yakima fold-and-thrust belt, is an area of topographical folds (or wrinkles) raised by tectonic compression. It is a structural-tectonic sub province of the western Columbia Plat ...

of east-tending long ridges formed by the folding of

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

Columbia River basalt flows.Complete Report for Saddle Mountains structures
, USGS Earthquake Hazards Program

References

External links

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Umtanum Ridge
Bivouac.com Ridges of Washington (state) Ridges of Yakima County, Washington Landforms of Kittitas County, Washington Washington placenames of Native American origin {{YakimaCountyWA-geo-stub