The Gros Ventre landslide ( ) is in the Gros Ventre Wilderness of Bridger-Teton National Forest,

Wyoming Wyoming () is a state in the Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to the s ...

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. The Gros Ventre landslide is east of

Jackson Hole Jackson Hole (originally called Jackson's Hole by mountain men) is a valley between the Gros Ventre and Teton mountain ranges in the U.S. state of Wyoming, near the border with Idaho, in Teton County, one of the richest counties in the Unit ...

valley and

Grand Teton National Park Grand Teton National Park is an American national park in northwestern Wyoming. At approximately , the park includes the major peaks of the Teton Range as well as most of the northern sections of the valley known as Jackson Hole. Grand Teton ...

. The landslide occurred on June 23, 1925, following melt from a heavy snowpack, several weeks of heavy rain, and earthquake tremors in the area. Approximately of primarily

sedimentary Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

rock slid down the north face of Sheep Mountain, crossed over the Gros Ventre River and rode up the opposite mountainside a distance of . The landslide created a large

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...

over high and wide across the Gros Ventre River, backing up the water and forming Lower Slide Lake. On May 18, 1927, part of the

landslide dam A landslide dam or barrier lake is the natural damming of a river by some kind of landslide, such as a debris flow, rock avalanche or volcanic eruption. If the damming landslide is caused by an earthquake, it may also be called a quake lake. Some ...

failed, resulting in a massive flood that was deep for at least downstream. The small town of

Kelly Kelly may refer to: Art and entertainment * Kelly (Kelly Price album) * Kelly (Andrea Faustini album) * ''Kelly'' (musical), a 1965 musical by Mark Charlap * "Kelly" (song), a 2018 single by Kelly Rowland * ''Kelly'' (film), a 1981 Canadi ...

, downstream, was wiped out, killing six people. It is one of the world's largest known examples of recent

mass wasting Mass wasting, also known as mass movement, is a general term for the movement of rock or soil down slopes under the force of gravity. It differs from other processes of erosion in that the debris transported by mass wasting is not entrained in ...

events aside from volcanic eruptions. Slide Lake is now much smaller than before the flood. Today, the landslide is partially reclaimed by the surrounding

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

but is still an obvious landmark from many vantage points in the Jackson Hole valley. It is easily accessible by traveling north from

Jackson, Wyoming Jackson is a town in Teton County, Wyoming, United States. The population was 10,760 at the 2020 census, up from 9,577 in 2010. It is the largest town in Teton County and its county seat. Jackson is the principal town of the Jackson, WY-ID Micro ...

or south from Moran, Wyoming and then taking the Antelope Flats road east off U.S. Route 26.

Etymology

In French, Gros Ventre means big belly / big stomach.

References

External links

* Natural disasters in Wyoming Landslides in the United States Geography of Teton County, Wyoming 1925 in Wyoming Bridger–Teton National Forest Landslide-dammed lakes Landslides in 1925 {{Wyoming-geo-stub