February - 2019

Therion is a complex software tool for archiving data which describes a cave, a cave system or a karst area.  Within the software is a cave map drawing tool.  Since 2003 the Mulu Caves Project has experimented with therion on a number of cave surveys none of which has yet produced definitive results.

A section of Wookey's 2003 Terikan survey.

In 2003 Wookey introduced the team to therion.  Wookey was involved with the software writers and had a high technical ability.  He alone understood the programme, which at that stage required software patches to be written as the technical aspects of complex map drawing unfolded.  Once digitised the cave map could be manipulated as the centre line changed therefore saving time redrawing surveys after each expedition when new discoveries were added.  Wookey took on the task of therionising the Terikan River System incorporating existing surveys and the new discoveries.  He produced a draft survey plan with most of the passage in outline only and with many technical problems still requiring attention.  Unfortunately he was unable to complete the survey.

In 2005 Andrew Atkinson took over the therion experiment and adopted a different approach.  He encouraged the rest of the team to participate and educated us in the basic use of the programme.  Andrew would act as the overseer and the whole team would share

Dave Clucas 'therionising' at the laptop. Photo © Matt Kirby

the workload.  For this expedition we took a scanner to Camp 5 so that the field drawings could be scanned and compiled into the therion survey as discoveries were made.  Everybody put in a big effort and by the end of the expedition a draft survey plan was produced of both Whiterock and Moon cave before the team left Mulu.  However, these were incomplete and as the team parted back at home, Andrew was left on his own.  A lengthy debate took place concerning the structure of the data resource and the merit of this type of survey drawing, and due to the sheer volume of technical work involved both surveys remained unfinished.

Between 2007 and 2009 Dave Clucas put in an enormous effort to bring about a result.  Self taught, Dave took Andrew’s Whiterock survey and added all the ’07 and ’09 discoveries to it.  Working both in the field, as before, and between expeditions Dave put in hundreds of hours on the Whiterock survey even extending it south to include Blackrock and most of the Clearwater System.  As the survey grew the programme data became more difficult to manage with many completed sections not appearing in the final composite plan.  To date the survey is still incomplete with many errors and complex junctions to fix and detail to add. The elevations have yet to be started!

The process for therionising the survey information is as follows;

  1. The survex line plot is converted into a therion line survey.
  2. The field drawings are scanned and used as the background image over the line plot.
  3. Therion ‘scraps’ are produced by digital tracing which is co-ordinated to the line plot.
  4. The individual scraps were then integrated into the Therion index file and joined together to produce the overall map.

The Whiterock entrance series in Therion

The major problems seem to be;

  • The expertise needed to run the programme deters most cave surveyors.
  • Some of the more complex aspects of survey drawing still have issues requiring programme writing skills to fix.
  • Survey building is too reliant on the individual scraps which dominate design features, and in a large survey become difficult to control.
  • The final drawing output is robotic in style and fails to produce an aesthetically pleasing product.

The Mulu Caves Project will continue to pursue this avenue of cave cartography whilst members of the team are willing to give up their time to do so.  It may take further advances in cave map software before acceptable results can be achieved.  The best solution may be to adapt software by industry standard manufacturers which is more user-friendly.  In the meantime the Mulu Caves Project will continue to experiment with other forms of both digital and traditional mapping.