FROM CAVE SURVEYING TO VIRTUAL FIELDWORK EXPERIENCE

The Cave and Karst Research and Education group of the University of Puerto Rico at Arecibo has been characterizing the geological properties of caves and study the karst geology of Puerto Rico for 8 years. During this period, more than 45 underrepresented undergraduate students participated in the measurements, design and development of 3D digital cartography methods. The first group of students measured the cave geometry using compass, inclinometers and laser rangefinders. After the measurements, they draw 780 vectors in graph paper to appreciate the cave map. After noticing that plotting all the vectors was an exorbitant task, we develop caveGEOmap free cave mapping software. CaveGEOmap is a user friendly Matlab executable that uses the cave measurements to create 2-D and 3-D maps of a cave with minimal user interaction. To verify the cave maps generated by caveGEOmap we used the ZEB1 LiDAR (Light Detection and Ranging). The Geoslam ZEB1 LiDAR provide us with millions of data points and creates a 3-D point cloud that was used to create a cave model. A comparison of both cave maps show that are similar at a large scale but in a smaller scale the data resolution of the LiDAR is much better as we expected. After collecting the LiDAR data, we can use that high resolution data to create virtual cave environments that can be explored by using Oculus. Additionally, other new method used in digital cartography is the SFM (structure from motion) photogrammetry, which creates 3D structure from 2D images, generating a 3D point cloud similar to LiDAR and can be processed to create virtual environment as well. From measuring with basic instrumentation, to the creation of software, to the use of LiDAR and SFM photogrammetry, this project represents a long journey of fieldwork experience from real data acquisition to virtual environment that engage and enhance the interest of the students and community in caves.