Provides geological information about potential ground movement or subsidence in GB. Some materials change in volume through seasonal wetting and drying whilst others undergo a rapid reduction in volume and can collapse when a load is placed on them (such as a building) and/or when they become saturated with water. Volume reductions may happen uniformly or unevenly causing different hazards for lenders, developers, building owners and insurers.

Includes indicators for the following hazards and a debris flow susceptibility model is available separately:
- collapsible deposits (volume reduction under load);
-compressible ground (as water is squeezed out from peat, clay);
- landslides (potential slope instability);
- running sand (fluidised by water);
- shrink swell (a major hazard in clay soils);
- soluble rocks (rock-salt, gypsum and limestone, including chalk).