Landslips

Landslips are a type of landslide involving the downslope movement of rock, earth, or debris driven by gravity and occurring along one or more slip surfaces. The term is used in some regions, particularly in Britain, to describe this class of rapid mass movement, and landslip is often treated as a synonym of landslide in general discussions.

Movements associated with landslips can take several forms. Translational slides occur along relatively planar surfaces, while rotational slides (slumps) move along curved shear planes with backward rotation. Other forms include debris slides, rockfalls, and rapid debris or earth flows, which may involve saturated material behaving as a moving mass. Movements can range from slow, creeping displacements to sudden, catastrophic shifts.

Causes and triggers include excessive rainfall or rapid snowmelt that saturates soils and reduces shear strength, changes in groundwater pressure, freeze-thaw cycles, earthquakes, and human activities that remove support or alter drainage patterns. Steep terrain, geological layering, and surface loading from structures or excavation can also contribute.

Impacts are typically to infrastructure and settlements located on or below the unstable area, including roads, railways, buildings, and utilities, as well as natural habitats. Signs of instability include ground cracks, bulging toe material, leaning trees, and new or widening scarps. Landslips can develop gradually or occur abruptly.

Mitigation and management focus on improving drainage, regrading slopes, installing retaining structures or rockfall barriers, stabilizing with vegetation or geotechnical measures, and implementing land-use planning and early warning systems to reduce risk and protect affected communities.