Glossary

Aven - A shaft entering the roof of a passage.

Bedding Plane - A line of weakness (usually) horizontal in Peak Cavern) between two beds of limestone, where water often first starts to form a passage. Low but wide crawls are often formed within bedding planes.

Belay Point - A safe anchorage point for ladder or rope.

Boulder Choke - A passage filled to the roof with boulders. Some boulder chokes are negotiable; others are impassable but may be the site of a dig. In all cases they require caution, as loose boulders are probably the most dangerous obstacle in caves.

Calcite - Calcium carbonate, the mineral of which both limestone and speleothems are mainly composed. Calcite is also often the main mineral found in 'veins' of various types in Peak Cavern.

Canal - A passage with deep water. Sometimes referred to as a "lake" if swimming is necessary.

Climb - A short vertical section in a passage, which can be negotiated fairly easily without the use of SRT or ladders. A "handline" is sometimes sued for convenience.

Crawl - A passage which is too low even for stooped walking. Progress is made by crawling on hands and knees, or even "flat out". A "wet crawl" involves lying in the water; not the most pleasant of caving situations!

Dig - A blockage of boulders, sand or mud which is being excavated by cavers hoping to explore new passages beyond.

Duck - A passage which us almost full of water. Cavers have to immerse themselves almost fully, sometimes using restricted airspace in order to pass such an obstacle.

Electron Ladder - A flexible lightweight metal ladder which can be rolled into a small bundle. Used for descending pitches, they should always be used in combination with a lifeline for safety reasons.

Flow Markings - Also known as "Scallops", these small depressions in the walls or floor indicate to the trained eye the direction and speed of the stream which formed the passage.

Fossil Passage - There are no processes of cave formation or associated processes taking place. For this to be present, the passage must be totally filled with sediment.Joint - A (vertical) line of weakness in the rocks, which water often penetrates when first forming a cave system. Vertical "pitches" are often associated with joints.

Lava Beds - layers of volcanic rock which are sometimes found in between the beds of limestone. They tend to stop water percolating downwards.

Limestone - The rock in which caves form, due to its tendency to dissolve slightly in contact with rainwater. The Derbyshire limestones are composed almost entirely of calcium carbonate.

Phreatic - A passage which formed when full of water. Often tubular, as solution of the limestone occurred evenly all around the walls.

Pitch - A vertical drop which is too difficult to climb without tackle.

Relic Passage (also known as Abandonded passage) - A passage which has now been abandoned by the stream which formed it, which now flows in passages at a lower level.

Resurgence - A point on the surface where water emerges.

Rift - Cavers' slang for a high narrow passage. A "cross-rift" is a common feature of caves, where a small chamber has formed in the roof of a passage, usually by solution along a joint. In long sumps these can form convenient airbells.

SRT - Abbreviation for single rope technique. Another method of descending vertical pitches in which a single rope is hung down the shaft clear of the walls to avoid all possibility of rope abrasion. When descending, the caver is attached to the rope by a friction device controlling the speed of the "abseil". To return up the rope a pair of mechanical clamps are used, along with some kind of harness, the technique being known as "prussiking". SRT. is unsuitable for novice cavers due to high level of competence needed to ensure safety.

Speleology - The scientific study of caves through such disciplines as archaeology, biology, geology and hydrology.

Speleothem - A deposit formed by the evaporation of water containing dissolved calcium salts. Often referred to by cavers as "formations", or "pretties". There are various types, ranging from "stalagmites" growing up from the floor or "stalactites" hanging from the roof, to delicate calcite dams ("gours") holding up clear pools of water or "helictites" (irregular fragile growths along passage walls). More rarely found are "cave pearls"; spherical bodies found in "nests" by dripping water. Their value is aesthetic or scientific rather than economic. They must therefore be preserved in their original condition for generations of cavers to see and enjoy.

Squeeze - A tight section of passage, where careful body movements are needed to avoid becoming stuck. Tight passages can cause inexperienced cavers to use up a lot of energy.

Sump - A flooded section of passage. Some are only a metre or so long and often a thick guide rope is left in place so that cavers can "free dive" through (holding their breath). However some sumps are several hundreds of metres long and can only be explored by properly equipped and trained cave divers.

Swallet - A point on the surface where water sinks underground. Also known as a "sink hole".

Traverse - A section of passage which is not crossed at floor level. Traversing usually involves jamming the body between two walls of a high narrow passage at the easiest level, or following a system of ledges along one wall of a larger passage to avoid water or loose boulders.

Vadose Canyon - A high but sometimes narrow passage caused by a stream flowing along the floor and constantly wearing it downwards.

Vein - A deposit of mineral material, typically of calcite, but sometimes containing lead or other ores (hence the evidence of past mining activity particularly in Speedwell cavern). There are several different kinds of veins, and sometimes cave passages are formed along them.