3D Mapping and Characterization of Sistema Zacatón from DEPTHX (DEepPhreaticTHermal eXplorer)

Abstract

Underwater exploration at Sistema Zacatón reached human limits when Jim Bowden descended to a depth of 289 meters April 6, 1994. In order to understand this karst system, unmanned robotic exploration is required to document the immense geometry of the underwater caves. The DEPTHX (DEep Phreatic THermal eXplorer) vehicle was developed with support from NASA to approach this problem, with the additional impetus to address robotic exploration in outer space. During the winter and spring of 2007, DEPTHX conducted three-dimensional (3D) underwater mapping missions of 4 cenotes in Sistema Zacatón: El Zacatón, Caracol, Poza Verde, and La Pilita. The detailed maps discovered no lateral tunnels connecting the cenotes, which are only 100-200 meters apart from each other. The deepest cenote, El Zacatón was bottomed out at a depth of 319 meters (339 m including above water cliff), making it the deepest underwater vertical shaft and second deepest underwater cave in the world. No side tunnels were discovered. However, the 3D data revealed geomorphic features of the cenotes to document how the karst system may have evolved through time. Spatial geochemical data collected contemporaneously during mapping missions indicate that water in the three warmest cenotes is extremely homogeneous, and the cooler cenote displays chemoclines similar to lacustrine type settings. The data collected by DEPTHX are being used with other types of geologic information to investigate the specific nature of hypogenic karstification that formed the cave system.

Nuevas herramientas, tecnologías y técnicas aplicadas en las ciencias geológicas: Panorama actual y perspectivas futuras

“…Aunque es una tecnología relativamente antigua, recientemente existen dispositivos de sonar compactos y portátiles, muy útiles para aplicaciones geoló-gicas. Aunque la tecnología sonar no es tan rápida y precisa como los escaneos laser, robots como el modelo DEPTHX desarrollado por Stone Aerospace realiza modelos 3D de con precisiones de 10 cm, como el modelo del sistema Zacatón en México (Gary et al, 2008). Otras posibles aplicaciones son la batimetría de lagos, ríos, esteros y mares, estimación de tasas de sedimentación, entre otros.…”

“…Con esta tecnología se puede realizar modelos tridimensionales de muy alto detalle de superficies irregulares complejas como cuevas (Canevese et al, 2009). Bajo el agua es posible utilizar tecnología sonar para obtener modelos batimé-tricos con resoluciones de hasta 10 cm (Gary et al, 2008). Combinando técnicas topográficas convencionales con geofísica y el uso de tecnología radar de alta penetración en la Antártida fue posible determinar los espesores de las capas de hielo y un modelo de la superficie bajo esta (NASA, 2013).…”

Autonomous Thin Spray-On Liner Application in Irregular Tunnel and Mine Roadway Surfaces

“…A solution demonstrated by (Lee, Choi, Park, Park, & Lee, 2007) incorporates the use of velvet tube lengths to reduce the beam width. (Gary et al, 2008) utilise narrow-beam sonars, 2° beam-width, to increase directional resolution for 3D spatial maps of underwater caves. Sonar range measurements were noisy and low resolution whilst the update rate and point density resulted in a more difficult mapping process compared to laser scanners.…”

Three-Dimensional Mobile Mapping of Caves

“…To our knowledge, our body of work represents the first instance of mobile mapping in nonsubmerged caves (Stone et al (2000) and Gary et al (2008) describe mapping underwater voids using sonar), and a significantly more efficient and complete method of surveying caves compared to the state-of-the-art. After describing the equipment and its use, we present results obtained from extensive scanning of significant parts of the Jenolan Caves and Koonalda Cave in Australia.…”