MODERN 3D DIGITAL CARTOGRAPHY: ZEB1 LIDAR AND CAVEGEOMAP

In these days, modern technology is being used to create cave maps to help speleologists to explore and characterize caves. Our research group are developing and using two modern techniques to create 3D digital cartography of caves; these are: i) ZEB1 LiDAR and ii) caveGEOmap. Light Detection And Ranging (LiDAR) is being used to create 3-D cave maps. The Geoslam ZEB1 (3-D Laser Mapping) hand held mobile LiDAR was used to obtain the measurements. This system provides us with more than 40,000 data points per second in a totally random three-dimensional pattern with a 270^o angular field of view. After the data collection, which provides us with millions of data points, a powerful computer and advance software are needed to create the 3-D high-resolution cave maps. Secondly, CaveGEOmap is a Matlab® code developed that uses basic surveyor cartography measurements to create 2-D and 3-D maps of the cave with minimal user interaction. Commonly, a cave cartographer will use a digital laser distance measurer, clinometer and a compass to obtain the measurements of the cave, however this method is time consuming and as a result few measurements are usually obtained. Our method consisted in measuring distances as a function of the azimuth and inclination for a total of 54 data points per station. Then, caveGEOmap evaluates the given measurements using Spatial Analysis and uses the data itself to estimate the necessary variables to produce the 2-D and 3-D cave maps. In this study, both methods will be presented and compared (based on data points collected, quality of data, time, cost effectiveness, maps created and surveying difficulties) for caves in the north coast karst belt region of Puerto Rico. In conclusion, comparisons between two modern cave cartography methods were used for this study and the main objective was to verify if caveGEOmap (uses basic surveyor measurements, is time consuming and inexpensive) method is comparable to the ZEB1 LiDAR (high quantity data collection, expensive and less time consuming) method.