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43-578: The British Cave Research Association ( BCRA ) is a speleological organisation in the United Kingdom . Its object is to promote the study of caves and associated phenomena, and it attains this by supporting cave and karst research, encouraging original exploration (both in the UK and on expeditions overseas), collecting and publishing speleological information, maintaining a library and organising educational and scientific conferences and meetings. BCRA

86-419: A back-sight to the previous station in the opposite direction. A back-sight compass reading that is different by 180 degrees and a clinometer reading that is the same value but with the reverse direction (positive rather than negative, for example) indicates that the original measurement was accurate. When a loop within a cave is surveyed back to its starting point, the resulting line-plot should also form

129-400: A cave. Cave maps, called surveys , can be used to compare caves to each other by length, depth and volume, may reveal clues on speleogenesis , provide a spatial reference for further scientific study, and assist visitors with route-finding. Caves provide a home for many unique biota. Cave ecologies are very diverse, and not sharply distinct from surface habitats. Generally however, the deeper

172-627: A centerline survey is Survex , which was originally developed by members of the Cambridge University Caving Club for processing survey data from club expeditions to Austria. It was released to the public in 1992. The centerline data can then be exported in various formats and the cave detail drawn in with various other programmes such as AutoCAD , Adobe Illustrator and Inkscape . Other programmes such as 'Tunnel' and Therion have full centerline and map editing capabilities. Therion notably, when it closes survey loops, warps

215-411: A closed loop. Any gap between the first and last stations is called a loop-closure error . If no single error is apparent, one may assume the loop-closure error is due to cumulative inaccuracies, and cave survey software can 'close the loop' by averaging possible errors throughout the loop stations. Loops to test survey accuracy may also be made by surveying across the surface between multiple entrances to

258-409: A fixed reference point to which to return at a later date. The measurements taken between the stations include: Coincident with recording straight-line data, details of passage dimensions, shape, gradual or sudden changes in elevation, the presence or absence of still or flowing water, the location of notable features and the material on the floor are recorded, often by means of a sketch map. Later,

301-639: A meeting in Valence-sur-Rhone , France in 1949 and first held in 1953 in Paris . The International Union of Speleology (UIS) was founded in 1965. The growth of speleology is directly linked with that of the sport of caving , both because of the stimulation of public interest and awareness, and the fact that most speleological field-work has been conducted by sport cavers . Karst is a landscape that has limestone underneath which has been eroded. Caves are usually formed through chemical corrosion via

344-494: A methodology in the 1960s to assess the accuracy, or grade , of a cave survey . It remains in common use today and is based on a scale of six grades. Speleology Speleology is a cross-disciplinary field that combines the knowledge of chemistry , biology , geology , physics , meteorology , and cartography to develop portraits of caves as complex, evolving systems. Before modern speleology developed, John Beaumont wrote detailed descriptions of some Mendip caves in

387-449: A point cloud rather than a series of linked stations. Video-based surveying also exists in prototype form. A survey team begins at a fixed point (such as the cave entrance) and measures a series of consecutive line-of-sight measurements between stations. The stations are temporary fixed locations chosen chiefly for their ease of access and clear sight along the cave passage. In some cases, survey stations may be permanently marked to create

430-492: A process of dissolution . Corrosion has several ways of doing this, it can be on carbonate rocks through chemical reactions, in gypsum and rock salt it can happen physically, and in silicate rocks and warm climate the decomposition of the materials can happen as well. A speleothem is a geological formation by mineral deposits that accumulate over time in natural caves . Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take

473-411: A reservoir is placed on one end of the tube, and a metal box with a transparent window is placed on the other. A diver's digital wristwatch with a depth gauge function is submerged in the box. If the rubber glove is placed on one station and the box with the depth gauge is placed on a lower one, then the hydrostatic pressure between the two points depends only on the difference in heights and the density of

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516-444: A similar set of steps which haven't changed fundamentally in 250 years, although the instruments (compass and tape) have become smaller and more accurate. Since the late 1990s, digital instruments such as distometers have started to change the process, leading to the advent of fully paperless surveying around 2007. The main variation on the normal methodology detailed below have been devices such as LIDAR and SONAR surveyors that produce

559-402: A sinkhole, frogs swept into a cave by a flash flood, etc. The two factors that limit cave ecologies are generally energy and nutrients. To some degree moisture is always available in actively forming Karst caves. Cut off from the sunlight and steady deposition of plant detritus, caves are poor habitats in comparison with wet areas on the surface. Most of the energy in cave environments comes from

602-400: A variety of forms, depending on their depositional history and environment. Their chemical composition, gradual growth, and preservation in caves make them useful paleoclimatic proxies. Caves have an absence of stable temperature , high relative humidity , low rates of evaporation and limited supply of organic material , which help in creating an environment which is highly favorable for

645-548: Is a national research and reference library based in the Peak District , owned by BCRA and staffed part-time by a librarian. It mostly comprises published and archived material collected by BCRA and its predecessor organisations, with a minority of the items on long-term loan from clubs and individuals. The library function with the financial assistance of the British Caving Association, through which

688-759: Is a registered charity in the UK, and a constituent body of the British Caving Association (BCA), undertaking charitable activities on behalf of BCA. The British Cave Research Association arose from a merger in 1973 of the British Speleological Association (BSA) and the Cave Research Group of Great Britain (CRG). When the National Caving Association (NCA) was formed in 1968, BCRA became one of its constituent bodies. Although NCA

731-421: Is regularly used in building construction for finding two points with the same height, as in levelling a floor. In the simplest case, a tube with both ends open is used, attached to a strip of wood, and the tube is filled with water and the depth at each end marked. In Russia, measuring the depth of caves by hydrolevelling began in the 1970s, and was considered to be the most accurate means of measuring depth despite

774-519: Is the Grotte de Miremont in France . This was surveyed by a civil engineer in 1765 and includes numerous cross-sections. Édouard-Alfred Martel was the first person to describe surveying techniques. His surveys were made by having an assistant walk down the passage until they were almost out of sight. Martel would then take a compass bearing to the assistant's light, and measure the distance by pacing up to

817-995: The Cave Radio & Electronics Group Journal . In 2013 BCRA published the first volume of a major work, Caves and Karst of the Yorkshire Dales , edited by Tony Waltham and David Lowe, with Volume 2 published in 2017. In 1996 the UK's annual caving conference (the 'BCRA Conference') was given a face-lift and re-titled Hidden Earth . Although BCRA still underwrites the event, it is now billed as being jointly hosted by BCRA and BCA. BCRA hosts an annual Science Symposium at which short papers are informally presented. Contributions are invited on any aspect of cave or karst science or caving technology and abstracts are published in Cave & Karst Science . BCRA has also hosted symposiums on Cave Technology, featuring contributions from its Special Interest Groups. The British Caving Library (BCL)

860-648: The National Geoscience Data Centre at the British Geological Survey (BGS), the archive material specifically relating to BCRA and its predecessor organisations was moved, in 2009, to BGS for safe-keeping in controlled storage conditions. For further information see the British Caving Library website, which includes an on-line catalogue of the collection, and an on-line audio archive. BCRA produced

903-400: The cartographer analyzes the recorded data, converting them into two-dimensional measurements by way of geometrical calculations. From them he/she creates a line-plot ; a scaled geometrical representation of the path through the cave. The cartographer then draws details around the line-plot, using the additional data of passage dimensions, water flow and floor/wall topography recorded at

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946-505: The 'father of modern speleology', who through his extensive and well-publicised cave explorations introduced in France the concept of speleology as a distinct area of study. In 1895 Martel founded the Société de Spéléologie , the first organization devoted to cave science in the world. Other early speleologists include Herbert E. Balch . An international speleological congress was proposed at

989-493: The 'national body' services formerly provided by NCA and BCRA. At the start of 2006, a new membership structure limited BCRA membership to BCA members, who now pay a supplement to join BCRA. Having passed on most of its functions to BCA, BCRA is now able to focus entirely on cave science, technology and heritage matters; the latter involving the cataloguing of the vast amount of library and archive material that BCRA has collected over

1032-421: The 1680s. The term speleology was coined by Émile Rivière in 1890. Prior to the mid-nineteenth century the scientific value of caves was considered only in its contribution to other branches of science, and cave studies were considered part of the larger disciplines of geography , geology or archaeology . Very little cave-specific study was undertaken prior to the work of Édouard-Alfred Martel (1859–1938),

1075-578: The assistant. This would equate to a modern-day BCRA Grade 2 survey. The first cave to have its centreline calculated by a computer is the Fergus River Cave in Ireland , which was plotted by members of the UBSS in 1964. The software was programmed onto a large university mainframe computer and a paper plot was produced. There are many variations to surveying methodology, but most are based on

1118-418: The cave becomes, the more rarefied the ecology. Cave environments fall into three general categories: Cave organisms fall into three basic classes: There are also so-called accidental trogloxenes which are surface organisms that enter caves for no survival reason. Some may even be troglophobes (“cave haters”), which cannot survive in caves for any extended period. Examples include deer which fell through

1161-548: The cave conditions and equipment available underground. Cave surveying and cartography , i.e. the creation of an accurate, detailed map, is one of the most common technical activities undertaken within a cave and is a fundamental part of speleology . Surveys can be used to compare caves to each other by length, depth and volume, may reveal clues on speleogenesis , provide a spatial reference for other areas of scientific study and assist visitors with route-finding. Traditionally, cave surveys are produced in two-dimensional form due to

1204-571: The confines of print, but given the three-dimensional environment inside a cave, modern techniques using computer aided design are increasingly used to allow a more realistic representation of a cave system. The first known plan of a cave dates from 1546, and was of a man-made cavern in tufa called the Stufe di Nerone (Nero's Oven) in Pozzuoli near Naples in Italy. The first natural cave to be mapped

1247-546: The difficulties in using the cumbersome equipment of the time. Interest in the method has been revived following the discovery of Voronja on the Arabica Massif in the Caucasus  – currently the world's second deepest cave. The hydrolevel device used in recent Voronja expeditions comprises a 50-metre (160 ft) transparent tube filled with water, which is coiled or placed on a reel. A rubber glove which acts as

1290-534: The disasters that can devastate or destroy underground biological communities. Speleologists also work with archaeologists in studying underground ruins, tunnels, sewers and aqueducts, such as the various inlets and outlets of the Cloaca Maxima in Rome . Cave survey A cave survey is a map of all or part of a cave system, which may be produced to meet differing standards of accuracy depending on

1333-402: The growth of microbes . Microbial assemblages in caves include archaea , bacteria , fungi and other micro- eukaryotes , these highly adapted microbial communities represent the living-backbone of cave ecosystems and play a key role in shaping structures and sustaining trophic networks. The creation of an accurate, detailed map is one of the most common technical activities undertaken within

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1376-447: The library is able to offer its services to all cavers and to all those interested in cave science and related topics. The library comprises a reference section and an archive section of older material. The reference section includes a large collection of books and journals on caving topics from Britain and abroad, which is frequently updated by donations and by journal exchanges with many caving clubs worldwide. Following an agreement with

1419-570: The passages to fit over their length, meaning that entire passages do not have to be redrawn. Unlike Therion's 2D warping capabilities, CaveWhere warps passages in 3D. This includes warping plan and profile sketches. CaveWhere also supports loop closure (using Survex) and provides a user friendly interface for entering and visualizing cave survey data. Terrestrial LiDAR units are increasing significantly in accuracy and decreasing in price. Several Caves have been "scanned" using both "time of flight" and "phase shift" LiDAR units. The differences are in

1462-565: The past, cavers were reluctant to redraw complex cave maps after detecting survey errors. Today, computer cartography can automatically redraw cave maps after data has been corrected. There are a large number of surveying packages available on various computer platforms, most of which have been developed by cavers with a basis in computer programming. Many of the packages perform particularly well for specific tasks, and as such many cave surveyors will not solely choose one product over another for all cartographic tasks. A popular program for producing

1505-882: The readings for consecutive pairs of stations gives the total depth of the cave. The accuracy, or grade , of a cave survey is dependent on the methodology of measurement. A common survey grading system is that created by the British Cave Research Association in the 1960s, which uses a scale of six grades. The equipment used to undertake a cave survey continues to improve. The use of computers, inertia systems, and electronic distance finders has been proposed, but few practical underground applications have evolved at present. Despite these advances, faulty instruments, imprecise measurements, recording errors or other factors may still result in an inaccurate survey, and these errors are often difficult to detect. Some cave surveyors measure each station twice, recording

1548-652: The relative accuracies available to each. The Oregon Caves National Park, was LiDAR scanned in August 2011, as were the Paisley Caves Archaeological dig site in SE Oregon. Both were scanned with a FARO Focus Phase shift scanner with +/-2mm accuracy. The Oregon Caves were scanned from the main public entrance to the 110 exit and were loop surveyed to the point of beginning. The data is not yet available for public use, but copies are retained by both

1591-419: The same cave. The use of a low-frequency cave radio can also verify survey accuracy. A receiving unit on the surface can pinpoint the depth and location of a transmitter in a cave passage by measurement of the geometry of its radio waves. A survey over the surface from the receiver back to the cave entrance forms an artificial loop with the underground survey, whose loop-closure error can then be determined. In

1634-419: The surplus of the ecosystems outside. One major source of energy and nutrients in caves is dung from trogloxenes, most of which is deposited by bats. Other sources are mentioned above. Cave ecosystems are very fragile. Because of their rarity and position in the ecosystem they are threatened by a large number of human activities. Dam construction, limestone quarrying, water pollution and logging are just some of

1677-485: The time, to produce a completed cave survey. Cave surveys drawn on paper are often presented in two-dimensional plan and/or profile views, while computer surveys may simulate three dimensions. Although primarily designed to be functional, some cavers consider cave surveys as an art form. Hydrolevelling is an alternative to measuring depth with clinometer and tape that has a long history of use in Russia. The technique

1720-407: The water, i.e. the route of the tube does not affect the pressure in the box. Reading the depth gauge gives the apparent depth change between the higher and lower station. Depth changes are 'apparent' because depth gauges are calibrated for sea water, and the hydrolevel is filled with fresh water. Therefore, a coefficient must be determined to convert apparent depth changes to true depth changes. Adding

1763-544: The years. One of BCRA's main activities is publishing. It publishes the periodical Cave and Karst Science (three issues per year) and the annual BCRA Review . The BCRA Review replaces Speleology , which was published from 2003 to 2014, as BCRA's Bulletin . Prior to 2003, Speleology was published under the title Caves & Caving . BCRA also publishes the Cave Studies series of booklets and manages various Special Interest Groups that also publish material, notably

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1806-538: Was recognised as the governing body for UK caving by the Sports Council it did not allow individual membership and so BCRA was seen by many as de facto the national body. This situation was resolved in 2005 when NCA was dissolved and a new body, the British Caving Association took over NCA's function as the governing body for UK caving (as recognised by the Sports Council). BCA consolidated various of

1849-619: Was the Baumannshöhle in Germany , of which a sketch from 1656 survives. Another early survey dates from before 1680, and was made by John Aubrey of Long Hole in the Cheddar Gorge . It consists of an elevational section of the cave. Numerous other surveys of caves were made in the following years, though most are sketches and are limited in accuracy. The first cave that is likely to have been accurately surveyed with instruments

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