Horse Ridge is series of

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates a ...

ridges in eastern

Deschutes County Deschutes County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 198,253. The county seat is Bend. The county was created in 1916 out of part of Crook County and was named for the Deschutes ...

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. It is located south of

Highway 20 Route 20, or Highway 20, may refer to: International * European route E20 Australia * Sturt Highway (NSW/VIC/SA) * Yarra Bank Highway Brazil * BR-020 Canada * Alberta Highway 20 * British Columbia Highway 20 * Manitoba Highway 20 *New B ...

, west of the Millican community, and south of the

Oregon Badlands Wilderness The Oregon Badlands Wilderness is a wilderness area located east of Bend, Oregon, Bend in Deschutes County, Oregon, Deschutes and Crook County, Oregon, Crook counties in the U.S. state of Oregon. The wilderness is managed by the Bureau of Land ...

. The Horse Ridge

Research Natural Area Research Natural Area is a designation for certain protected areas in the United States. Research Natural Areas (RNAs) are part of a nationwide network of ecological areas set aside for both research and education. The network includes areas man ...

occupies predominantly north and northeast facing slopes of the ridges. It was established in 1967. The

Brothers Fault Zone The Brothers Fault Zone (BFZ) is the most notable of a set of northwest-trending fault zones including the Eugene–Denio, McLoughlin, and Vale zones that dominate the Geology of Oregon, geological structure of most of Oregon. These are also ...

bisects the ridges and exposed

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

lava rock has been dated to 7.5 ma. Horse Ridge is a winter

mountain biking Mountain biking is a sport of riding bicycles off-road, often over rough terrain, usually using specially designed mountain bikes. Mountain bikes share similarities with other bikes but incorporate features designed to enhance durability and pe ...

recreation area with about of trails.

References

{{authority control Landforms of Deschutes County, Oregon Mountains of Oregon National Natural Landmarks in Oregon Ridges of Oregon Volcanoes of Deschutes County, Oregon Volcanoes of Oregon Volcanoes of the United States