Karst glossary
Last updated on January 29, 2024A-C
Archaeology – the scientific study of the physical evidence of past human cultures.
Armouring – placing non-erodible material (for example, riprap) over material that may be subject to erosion.
Ballast – rock, gravel, or other stabilizing material placed on top of subgrade or overland ground during road building.
Carbonate bedrock – rock consisting mainly of the carbonate minerals calcite and dolomite.
Catchment – the surface area drained by various sized watercourses.
Cave – a natural cavity in the earth that connects with the surface, contains a zone of total darkness, and is large enough to admit a human. For the purposes of cave management, this term should also include any natural extensions, such as crevices, sinkholes, pits, or any other openings, that contribute to the functioning of the cave system.
Cave decorations – secondary mineral deposits formed in caves; synonym, speleothems.
Caves with thin ceilings – caves where the depth of the overlying bedrock is less than three times the width of the cave passage (Derek Ford, pers. comm., December 1999) See Figure 6 - 1 (GIF, 19KB).
Conduit – a subsurface stream course completely filled with water, and always under hydrostatic pressure.
Cross-ditches – ditches excavated across a road at an angle, and at sufficient depth, with armouring as appropriate, to divert both road surface water and ditch water across the road.
D-K
Dolomite – a mineral composed of calcium magnesium carbonate. Rock is chiefly composed of the mineral dolomite. Also called dolostone.
Dry valley – a valley that lacks a surface water channel.
Endhaul – to move excavated material from one section of a road to another, or to a disposal site, during road construction or modification.
Ephemeral stream – a stream or portion of a stream that flows only in direct response to precipitation, drying up shortly after precipitation ceases.
Epikarst – the upper surface of karst, consisting of a network of intersecting fissures and cavities that collect and transport surface water and nutrients underground; epikarst depth can range from a few centimetres to tens of metres.
Geotextile material – a synthetic material placed under road fill, bridges, or reinforced slopes with the primary purpose of limiting fine aggregate transfer.
Grubbing – removal of stumps, roots, embedded logs, organics, and unsuitable soils before, or concurrently with, subgrade road construction.
Grike – a deep, narrow, vertical or steeply inclined rectangular slot in carbonate bedrock, developed by solution along a joint or fracture.
Gypsum – the mineral, hydrated calcium sulfate.
Halite – the mineral form of sodium chloride (NaCl), or rock salt.
Karren – channels or furrows separated by ridges resulting from solution on bedrock surfaces; the term is also used broadly to describe a variety of superficial solution forms on the surface of bedrock.
Karst resources – refers to all components of a karst system, including the physical, biological, and aesthetic aspects of a karst landscape.
Karst spring – underground stream that emerges at the surface; also known as a rising stream.
L-R
Limestone – a sedimentary rock comprised primarily of calcite.
Marble – limestone that has been recrystallized and hardened by heat and pressure.
Overburden – material of any nature (soil, sand, silt, clay), consolidated or unconsolidated, that overlies deposits such as bedrock, ores, or coal.
Overlanding – placing road construction fill over unstripped organic soil, stumps or other vegetative materials for the purpose of distributing vertical loads over soft ground, whether or not the fill is supported by corduroy or geotextiles.
Paleontology – science that studies fossil remains, both plant and animal, from past geological ages.
Physiographic – pertaining to the origin and evolution of landforms.
Road deactivation – measures taken to stabilize roads and logging trails during periods of inactivity, including the control of drainage/runoff, the removal of sidecast where necessary, and the re-establishment of vegetation where permanent deactivation is required.
Road rehabilitation – involves the removal of a road and restoration of the original slope and natural drainage patterns to prevent erosion and re-establish site productivity.
S
Settling basin – small ponds or basins where water flows are contained to enable suspended sediment to settle before the flow is discharged into a stream.
Shaft – a deep vertical or nearly vertical solution hole, generally cylindrical in shape, with no passages or chambers leading from it.
Sidecast – moving excavated material to the downslope side during road and landing construction.
Significant surface karst feature – details for determining the significance of surface karst features are provided in Appendix C of Karst Inventory Standards and Vulnerability Assessment Procedures (RISC 2003).
Significant cave – information on classifying caves for their significance is provided in RISC (2003).
Silt/Sediment trap – a device for trapping or otherwise preventing silt or sediment from entering a stream (for example, silt fence, filter fabric).
Sinkhole – a topographically closed karst depression, wider at the rim than it is deep; commonly of a circular or elliptical shape with a flat or funnel-shaped bottom.
Solutional cavities – cavities formed primarily by the solution action of water on carbonate bedrock.
Sorbents – materials capable of adsorption (attracting and holding substances upon its surface [e.g., charcoal]) and absorption (sucking in and holding a substance within a porous material [e.g., sponges]) used to clean up spills.
Speleothems – secondary mineral deposits formed in caves, such as stalactites or stalagmites. Also known as cave formations or cave decorations.
Subgrade construction – removal of obstacles and materials necessary for the construction of a road.
Subsidence – movement in which surface materials are displaced vertically downward, with little or no horizontal component.
Swallet – location where a stream sinks underground, often associated with a stream flowing into a cave entrance; also swallow hole.
T-Z
Troglobite – a creature that lives permanently underground, beyond the daylight zone of caves, and cannot survive outside the cave environment.
Troglophile – a facultative cave-dwelling animal that may complete its life cycle in a cave, but can also survive in above ground habitats.
Trogloxene – an animal that enters caves for various reasons, but does not live there permanently (e.g., bats).
Waterbars – shallow ditches excavated across a road at an angle to prevent excess surface flow and subsequent erosion of road surface materials.
Windthrow – uprooting of trees by the wind.