Landslides
Buffalo Creek Landslide, Bighorn Basin, Wyoming
In November 2016, a Discovery Channel camera crew filmed geologists from the Wyoming State
Geological Survey at the site of the Buffalo Creek Landslide in the Bighorn Basin. Hunters
noticed the landslide in October 2015. The video, produced and owned by Discovery Channel,
can be viewed on the left. Follow the link below for an interpretation based on review of
historic photographs, web sources, photographs of the slide, existing data, and local geology.
Landslide near West Fork of Buffalo Creek
Landslides in Wyoming
A landslide is the downslope movement of a mass of rock or soil driven by gravity. Landslides, which are also known as mass movements, encompass a variety of processes, deposits,
and landforms that can be broadly classified into slides, flows, falls, topples, and spreads. Examples of specific landslide types include rockfalls, debris flows, and slumps.
Landslides can damage or destroy roads, pipelines, structures, and utility lines. They can also temporarily block rivers with earthen dams, which when overtopped can cause flooding
downstream. When landslides occur in populated areas, they can cause significant damage and loss of life. Rock type, slope angle, hydrology, and geologic structure are some of the major
factors that determine whether an area is prone to landslides. Human activities, such as road construction and surface water diversion, can also have an impact on landslide occurrence.
Landslides occur every year in Wyoming, however, most occur in remote areas and
do no typically cause damage. The WSGS has mapped more than 30,000 landslides throughout the state.
Susceptibility to Deep-seated Landslides in Wyoming (Open File Report 2019-07)
Landslide Database
Preliminary Map of Landslides in Wyoming
Types of Landslides
Debris Flow—A mass of loose, water-laden, and poorly sorted debris of fragmented rock, soil, and mud that surges down a slope or through a stream channel.
Debris flows can be triggered by heavy rainfall, rapid snowmelt, or by other landslides.
Falls—Detachment and rapid downward movement of material down a near-vertical slope.
Topples—Forward rotation of a mass of rock or soil out from a free face, with the axis of rotation below the center of mass.
Creep—Slow, imperceptible, downward flow of soil or rock material along the surface of a slope.
Rotational landslide (slump)—Block of material that slides down a slope along a concave-up rupture surface and that may rotate backwards about an axis parallel to the slope’s contour.
Translational landslide—Block of material that slides downslope along a planar rupture surface, which is usually formed by a geologic discontinuity (ex: soil interface, bedding plane, fault) parallel to the ground.
Contact:
James Mauch, james.mauch@wyo.gov