Mima mounds

PatternsSoil

Mima mounds are low, flattened, circular to oval, domelike, natural mounds that are composed of loose, unstratified, often gravelly sediment that is an overthickened A horizon. These mounds range in diameter from 3 to more than 50 m; in height 30 cm to greater than 2 m; and in density from several to greater than 50 mounds per hectare, at times forming conspicuous natural patterns. Mima mounds can be seen at the Mima Mounds Natural Area Preserve in Washington state. "Mima" is a name derived from a Chinook Jargon term meaning "a little further along" or "downstream".Theories for the origin of Mima mounds include burrowing by pocket gophers; accumulation of wind-blown (aeolian) sediments around vegetation to form coppice dunes or nebkhas; seismic ground shaking by major earthquakes, though none have been observed to form Mima mounds; and shrinking and swelling of clays in hog-wallow or gilgai landforms. Though the definitive Mima mounds are common in North America, it has not been shown that all North American mounds result from the same causes. Superficially similar phenomena occur on all continents, and the proposed causal factors do not occur in all regions that have been studied. Nor is it clear that all such mounds really are the same, either physically or functionally; for example, the so-called fairy circles of Southern Africa tend to be less mound-like and occur in different climatic and ecological conditions from Mima mounds. Furthermore, it has been argued that the possibly distinct heuweltjies of the South Western Cape region of South Africa are of an origin far different from either.

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Mima mounds
Mima Mounds South Loop Trail,

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Latitude	Longitude
N 46.89856 °	E -123.05048 °

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Mima Mounds South Loop Trail

Mima Mounds South Loop Trail
98556
Washington, United States
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Nearby Places

Mima Mounds Natural Area Preserve

Mima Mounds Natural Area Preserve is a state-protected Natural Area in southwest Washington state, United States. The preserve includes some of the Washington mima mounds, the origin of which still is not fully understood. The site comprises 637 acres (258 ha) of Garry oak woodland, oak savanna, and prairie grasslands. Several state and federal endangered species of butterfly depending on the unique prairie conditions can be found in the preserve, including Mardon skipper, zerene fritillary, Puget blue and Taylor's checkerspot.In 1966, the mima mounds were designated a National Natural Landmark.

Waddell Creek (Black River tributary)

Waddell Creek is a stream in Thurston County in the U.S. state of Washington. It is a tributary to the Black River.Waddell Creek was named after the family of Robert Waddell, which settled near its course in the 1850s.

Bordeaux, Washington

Bordeaux is a ghost town in Thurston County, in the U.S. state of Washington.

Littlerock, Washington

Littlerock is an unincorporated community in Thurston County, Washington, United States. Littlerock is 11 miles (18 km) southwest of Olympia. The town is west of Interstate 5 and Maytown. Littlerock is located near several protected lands, such as the Mima Mounds Natural Area Preserve and Capitol State Forest.

Mima, Washington

Mima is an unincorporated community in Thurston County, in the U.S. state of Washington. The area is located between Littlerock and Gate.

Mill Creek (Thurston County, Washington)

Mill Creek is a stream in Thurston County, Washington. It is a tributary of Mima Creek.Mill Creek was named for a sawmill along its course.

Mima Creek

Mima Creek is a stream in Thurston County in the U.S. state of Washington. It is a tributary to the Black River. The upper course of Mima Creek contains the Mima Falls, a waterfall."Mima" is a name derived from a Native American language meaning "a little further along" or "downstream".

Salmon Creek (Black River tributary)

Salmon Creek is a stream in Thurston County in the U.S. state of Washington. It is a tributary to the Black River.Salmon Creek was so named on account of its stock of salmon.

Lake Lucinda

Lake Lucinda is a lake in the U.S. state of Washington. It is impounded by the Lake Lucinda Dam.Lake Lucinda took its name from a nearby residential complex.

Noski Creek

Noski Creek is a stream in Thurston County in the U.S. state of Washington. It is a tributary to Waddell Creek.A variant name is "Noschka Creek". The creek was named after a pioneer who settled near it in the 1880s.

Rochester, Washington

Rochester () is a census-designated place (CDP) in Thurston County, Washington, United States. It was founded in 1852, and the 2020 census recorded its population at 6,064. According to the United States Census Bureau, the CDP has a total area of 2.3 square miles (6.0 square kilometers), all of it land. Rochester Schools had 2,105 students registered in 2021-22 School Year.

Delphi, Washington

Delphi is an unincorporated community in Thurston County, in the U.S. state of Washington. The community is located approximately west of Tumwater and Black Lake. The town of Littlerock lies to the south.