A SUBMARINE IMAGING AND LASER PROFILING SYSTEM AND ITS APPLICATION TO COLD SEEP SITE INVESTIGATION OFF SOUTHWESTERN TAIWAN

Submarine vehicles (SVs) have been widely used in marine investigations that have greatly enhanced the human ability to explore the deep ocean. High quality videos and photos obtained with cameras mounted on SVs are essential data of submarine investigations for the time being since they may provide indispensable information for the study of hydrothermal and cold seep systems. In this paper, a Remotely Operated Vehicle (ROV) "Faxian", equipped with a 4500-m-rated L1000 Imaging and Laser Profiling system designed and supplied by Cathx Ocean Ltd was introduced and applied at the Taiwan Ridge for cold seep site investigation, The imaging and profiling system includes a M12 L1000 Dual Mode Laser Profiler Camera and an Aphos 16(S16) 110VAC LED light and a DGL300 Green Line Laser. This system was fastened to the bottom of "Faxian" and was pointed downward at the seafloor. In 2016, more than 300 thousand seafloor images of the cold seep site with coordinate information were collected covering an area of around 20 000 m² in about 30 hours with a imaging frequency of 3 images per second. A high-definition panoramic image covering the most part of the cold seep site was finally achieved by merging all the georeferenced photos. Based on this panoramic image, seabed features and the scales and distribution patterns of these features were analyzed. The installation and successful application of the imaging and laser profiling system will significantly enhance our ability to explore the deep oceans.