Seafloor characterization in the southernmost Okinawa Trough from underwater optical imagery

Abstract

This paper presents the seafloor survey results obtained in 2016 and 2017 using four deep-towed vehicles, developed by the Institute of Undersea Technology at National Sun Yat-sen University, for investigating mineral resource potential offshore northeastern Taiwan. The deep-towed vehicles include the Abyss Twist-pair Imaging System (ATIS), the Video-guided Multi-corer (V-Corer), the TV-guided Grabber (TVG), and the Fiber-optical Instrumentation Towed System (FITS). The seafloor video surveys and sampling were conducted at five survey sites in the southern Okinawa Trough through five survey cruises. A total of 82.69 km of seafloor survey tracks were accomplished and plenty of seafloor characteristics and ecological phenomena were observed through the four deep-towed vehicles. The seafloor survey results, including the video data and the samples of animals, sediments, and mounds, have been provided to different scientific teams for conducting research on marine geophysics, marine geology, marine geochemistry, and marine ecology. The video data can be cross-checked and used as the supporting evidence for the analysis results from the scientific researchers.

Key points

• Deep-towed vehicles, ATIS, V-Corer, FITS, and TVG, are utilized for seafloor surveys

• 82.69 kilometers of survey tracks are accomplished through the deep-towed vehicles

• Video data collected are strong evidence for mineral related seafloor features