Umtanum Ridge is a long anticline

Anticline

In structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. The term is not to be confused with antiform, which is a purely descriptive term for any fold that is convex up. Therefore if age relationships In structural geology, an anticline is a fold that is...

 mountain

Mountain

Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...

 ridge

Ridge

A ridge is a geological feature consisting of a chain of mountains or hills that form a continuous elevated crest for some distance. Ridges are usually termed hills or mountains as well, depending on size. There are several main types of ridges:...

 in Yakima County

Yakima County, Washington

Yakima County is the second largest county by area in the U.S. state of Washington. It is named after the Yakama tribe of Native Americans. In the 2010 census, its population was 243,231...

 and Kittitas County in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Washington. It runs for approximately 55 miles east-southeast from the Cascade Range

Cascade Range

The Cascade Range 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, and the notable volcanoes known as the High Cascades...

, through the Yakima Training Center

Yakima Training Center

The Yakima Training Center is a United States Army training center located in south central Washington state. It is bounded on the west by Interstate 82, on the south by the city of Yakima, on the north by the city of Ellensburg and Interstate 90, and on the east by the Columbia River...

 to the edge of the Columbia River

Columbia River

The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

 at Priest Rapids Dam

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 24 miles south of the town of Vantage, and 47 miles...

 and Hanford Reach

Hanford Reach

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

. The eastern end of Umtanum Ridge enters Hanford Reach National Monument

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...

 and the Hanford Site

Hanford Site

The Hanford Site is a mostly decommissioned nuclear production complex on the Columbia River in the U.S. state of Washington, operated by the United States federal government. The site has been known by many names, including Hanford Works, Hanford Engineer Works or HEW, Hanford Nuclear Reservation...

. Umtanum Ridge is paralleled on the north by Manastash Ridge

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...

 and on the south by Yakima Ridge

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 eastern end at Hanford Reach National Monument and the...

. The Yakima River

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. The length of the river from headwaters to mouth is , with an average drop of .-Course:...

 cuts through the ridge at the Umtanum Ridge Water Gap

Umtanum Ridge Water Gap

Umtanum Ridge Water Gap is a geologic feature in central Washington State in the United States.The Umtanum Ridge Water is a water gap cut by the Yakima River through Manastash and Umtanum Ridge anticlines, which are part of the Yakima Fold Belt near the western edge of the Columbia River Plateau...

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Umtanum Ridge is part of the Yakima Fold Belt of east-tending long ridges formed by the folding of Miocene

Miocene

The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...

 Columbia River basalt flows

Columbia River Basalt Group

The Columbia River Basalt Group is a large igneous province that lies across parts of the Western United States. It is found in the U.S. states of Washington, Oregon, Idaho, Nevada, and California...

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External links

• Umtanum Ridge, Bivouac.com