Landslides in British Columbia - Glossary

Avalanche

a large mass of snow, ice, soil, rock, or mixture of these, which falls or slides very rapidly under the force of gravity.

Bed

a layer of rock, usually sedimentary or volcanic.

Bedrock

a term used to describe the solid rock that underlies soil or other unconsolidated material.

Creep

the gradual movement of soil and other materials down a slope.

Earthquake

A naturally occurring shaking motion of the Earth's surface. Earthquakes are caused when stress, building up within rocks of the Earth's crust, is released in a sudden jolt.

Fall

a landslide in which material free falls.

Flow

viscous to fluid-like motion of debris down a slope.

Geotechnics

the use of engineering principles to understand how earth materials, such as soils and rocks, behave. This knowledge is applied to better design engineering structures.

Glacial sediments

sediments which form as a result of the actions of ice or glaciers.

Glaciolacustrine

pertaining to lakes dammed by or bordering glaciers.

Ground water

water which occurs underground, as opposed to surface water.

Joint

a fracture or parting in rock without any apparent displacement.

Landslide

a general term used to describe the down-slope movement of soil, rock and organic materials under the influence of gravity. It also describes the landform that results.

Metamorphic rocks

rocks which have formed from pre-existing rocks due to changes in temperature, pressure, stress or chemistry.

Sedimentary rocks

rocks formed by the accumulation of fragments, or the precipitation of dissolved material, that result from the weathering of pre-existing rocks.

Slide

the movement of rock or unconsolidated material parallel to planes of weakness and occasionally parallel to slope.

Slump

the complex movement of materials on a slope; includes rotational slump.

Topple

the end-over-end motion of rock down a slope.

Torrent

a sporadic and sudden channelized discharge of water and debris.

Unconsolidated

loose sediment that has not been cemented or otherwise converted to solid rock.

Volcanic rocks

rocks which result from volcanic action at, or near, the surface of the Earth such as lava flows or ash deposits.

Weathering

the disintegration of rocks on the Earth's surface by the action of rain, frost, heat, wind, etc.

Landslides in British Columbia was originally produced as Information Circular 1993-7 by the BC Geological Survey of the B.C. Ministry of Energy, Mines and Petroleum Resources in cooperation with the B.C. Ministry of Health, the B.C. Ministry of Transportation and Highways, the B.C. Ministry of Environment, Lands and Parks, the B.C. Ministry of Forests, the B.C. Provincial Emergency Program, and with the assistance of the Geological Survey of Canada.

Copies are available from:

Publications Office,

BC Geological Survey

Ministry of Energy, Mines & Petroleum Resources

PO Box 9333, Stn. Prov Gov't

Victoria, B.C.
V8W 9N3