Session Coordinator: Bob Hoke

Tips for Efficient Cave Surveying Bob Hoke, 6304 Kaybro Street, Laurel MD 20707 bob@hoke.net This presentation describes some ways that a survey team can improve their productivity and efficiency by “working smart, not hard.” Among the techniques described are allocating tasks so that no team member is overloaded or under-utilized, defining the responsibilities of each team member, placing stations to facilitate easy shots, taking readings in a consistent order, taking advantage of geometry to make shots easier to read, avoiding reading and recording errors, testing instruments before each trip, agreeing in advance on how dimension data is to be recorded, carrying instruments to faclitate quick use, using a small flashlight to l ight stations for backshots and knowing when to quit and head out of the cave An Analysis of Random and Systematic Surveying Errors Dale Andreatta, SEA Limited, 7349 Worthington-Galena Road, Columbus, OH 43085 dandreatta@sealimited.com An analysis was performed on various types of surveying errors, with the errors falling into two categories: random and systematic. Random errors are errors that are likely to be off in one direction more than the other, and may be large or small in magnitude. Random errors come from instrument readability (usually on the order of 1-2 degrees) and “blunders,” which can be small or large. Systematic errors are errors that are consistently off in one direction. Systematic errors generally come from instrument offset. This analysis concentrated on compass and inclinometer readings in longer passages. Analysis was performed using statistical methods and by numerical experimentation where 50 shots of actual survey data was taken and errors were assigned to the data. The differences between the data with errors and the data without error were calculated. The conclusions were as follows: Random errors caused by instrument readability consistently cancel out in longer passages. Therefore, meticulous matching of the foresight and backsite readings beyond that which serves to catch large blunders is not helpful. Instrument offsets of even a half degree give much larger final errors, even if the instrument offset is smaller than the readability of the instrument. This is because systematic errors accumulate rather than cancel. Fairly frequent blunders of 10 degrees make less difference in the final answer than instrument offset. Aside from preventing major survey blunders, the best way to improve survey data is to carefully take into account the differences between survey instruments. Suvey and Cartography of Marengo Cave, Indiana Bob Richards, 1206 Spinnaker Way, Sugar Land TX 77478 brichards@earthlink.net Marengo Cave is a beautiful show cave in southern Indiana that was originally mapped by the state in 1932. A new survey was done in September 2003. Using modern cartographic techniques, a more accurate and detailed map was generated. Surveying caves using laser technology and mapping caving using computer software will be discussed. Enhancing Workflow in Digital Cartography Brandon Kowallis, Timpanogos Cave, RR1 Box 200, American Fork, UT 84003 brandon@brandonkowallis.com While the advent of computer mapping has greatly improved the potential of the cave map, digital maps often sacrifice that timeless human fluidity of a hand-drawn map for machine-like repetitions that make us say, “thats definitely digital.” This presentation will focus on various features in Adobe Illustrator that allow you to speed up the cartographic process while creating maps that allow a digital cartographer to keep that timeless hand-drawn appearance. We will use layers to make global changes to specific features, generate brushes to cut time from drawing the minute details, and copy and manipulate forms to create repeating shapes that don’t resemble computerized duplicates. Field Cartography for the Xiangxi Expedition to Hunan Province Pat Kambesis, Hoffman Environmental Research Institute, Dept. of Geography & Geology, Western Kentucky University, Bowling Green, KY 42101. pnkambesis@juno.com In March of 2004, a team of cavers sponsored by Hoffman Institute and The Guilin Institute of Karst and Geology assisted with field assessment for a hydrologic project that was being conducted by the Xiangxi Engineering/hydrology Group. The purpose of the expedition was to evaluate the Dalong Cave System and surrounding karst area for the feasibility of constructing an underground dam and a surface reservoir. Using various data reduction, plotting, 3D analysis, cartography, and GIS software, field maps were generated in order to help the Chinese hydrology project group visualize the caves, karst features and topography of the area. This talk will review the methods used to produce useful maps in the field from basic cave survey data, GPS data, and digital elevation models. Auriga, or Trading Your Survey Notebook for a PDA Luc Le Blanc 5980, rue Saint-Anre, Montreal, Quebec, Canada H2S 2K4, lleblanc@cam.org The Auriga cave survey software for Palm OS was originally written to assist in the development of an electronic sensor box designed to automatically acquire azimuth and slope measurements, but has now evolved into a small survey notebook replacement for in=cave use and a lighter weight laptop replacement while at camp. Surveyors can see the cave map on the screen while doing their survey, and data does not need to be transcribed later, thus preventing many blunders throughout the process. Despite the smaller screen and slower CPU of Palm devices (vs PCs), Auriga offers graphical and spreadsheet rendition of cave passages, survey stations, and survey shots between them. Thanks to sessions, a concept already present in most cave survey software, surveyors can free their mind of instrument calibration, varing magnetic declination, and mised measurement units. This allows Auriga to faithfully store survey data exactly as input, applying corrections and conversions when computing coordinates. Several effici ent design aspects provide the cave surveyor with a highly configurable and ergonomi interface, even when operating through a windowed protection box. Once back on the surface, survey data can be sent to other Palm devices through an IR bean or uploaded onto a computer and converted into common cave survey file formats via a software “conduit”. The Auriga freeware is under intensive and constant evolution; support for networks of severa caves and loop closure are currently in the works, while on-screen freehand sketching of cave walls and details remain the ultimate goal. Home