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Geographical Information Systems are now used for all sorts of purposes from town planning to epidemic monitoring.

GPS receivers are used extensively these days for recording the location of cave entrances. These data can be exported as a gpx file which can be opened in Google Earth. These will show as a waypoint or a Placemark as it's known in Google Earth. This is the simplest form of georeferencing. The points show on a map of the world and each point can be given a name and can have a symol assigned to it.

Some cave survey software has the ability to export cave data in many formats. Some of these formats can be used in other programs such as Google earth or GIS programs. Therion will export kml and esri. 

Bukit Agung on Google EarthWhen working in Therion one of the checks I make is to export a kml (keyhole markup language) file and open it in Google Earth. This allows me to quickly check if fixed stations put the cave in the correct geographical loacation. It's quite easy to mistype a coordinate or to reverse the x and y coordinates resulting in a Derbyshire cave appearing in the middle of the Pacific. Of course, you can only create a kml if you have a georeference point (ie some global coordinates). Most if not all cave survey software create surveys by default in a local or aribtrary coordinate sytem.

Peak Caves DistributionGIS or Geographical Information Systems give the abilty to interrogate data and there are many tools available for sorting and symbolising geographical data. In caving terms the ability to interrogate datasets can be quite useful. In it's simplest form it may be a matter of checking out where most entrances occur to enable searching for new caves to be more focussed. Perhaps the majority of caves are found around the periphery of a limestone area or between two altitudes maybe related to a particular bed. Of course the ability to perform these queries will depend on those data being available. If you only record the latitude and longitude you can find the altitude by looking at a map but if you know where the limestone boundary is or which beds are at which altitudes then you have more possibilites. Fortunately much of this data collection has already been done for us and may well be available for free on the internet.

I have started to use GIS for cave surveys but am still only scratching the surface.

ArcGis is commonly used commercially but is only available for the Windows platform and it's expensive.