The ROV cruise, led by Tongji University, as a finale of the 8 years of the NSFC’s “South China Sea Deep” Program, was accomplished on May 19th. The Remotely Operated Vehicle for Ocean Sciences (ROPOS) carried out in situ observations, experiments and sampling of the seabed from 1,000 to 4,000 meters in the northeast and central part of the South China Sea, focusing on the seamounts, deep-sea sediments, and cold seep systems.
During this first ROV cruise onboard R/V TKK, the dynamic positioning system (DP), the acoustic positioning system (HiPAP101), and the multi-beam seabed mapping system (EM122), ensured precise positioning of ROV in the deep ocean.
What is an ROV?
ROV stands for Remotely Operated Vehicle. It is an underwater robot, sometimes known as a remote-controlled submarine, controlled by pilots on a ship. The ROV is connected to the ship by a umbilical cable, that contains wires running communications and power to the vehicle.
The ROPOS is a 40 hp Science/Work Class ROV capable of operating at depths of up to 5000 m, equipped with 2 x Shilling Robotics TITAN 4 Manipulators, can be fitted with a bio-box platform, two swing arms, four Niskin bottles, two HD Cameras, core tubes, a suction sampler, magnetometer, M3 multi-beam, current meter and CTD, etc. The ROPOS is capable of 24-hour continuous underwater operations.
A dive of ROV ROPOS. Photo: Weidi Yang
Several important discoveries in geology, biology and sediment dynamics have been acquired during this cruise, with a series of high-quality data and samples collected. “It’s the first time to discover paleo-hydrothermal zones in the South China Sea, which were named as Nan-ming and Lou-lan respectively,” said Prof. Huaiyang Zhou, Chief Scientist of this expedition. “Samples of paleo-hydrothermal chimneys have been collected.”
ROPOS offered a continuous stream of imaging, observation and sampling. Photo: ROPOS
Special cold seep ecosystem
Using high-definition cameras and multi-beam instruments fitted on ROPOS, a high-resolution seabed mapping and biocenosis survey was conducted in the 100x100 m2 main developing area, with a line spacing of 10 m. This is the first time such high-precision cold seep biocenosis photos were taken in China.
A high-definition image of cold seep captured by the camera fitted on ROPOS. Photo: ROPOS
This cruise had a strong flavor of ocean science outreach and broadcasts. Daily updates about ROPOS operation were posted onto R/V TKK’s Weibo official account. Two live broadcasts of the ROV deep-diving operation were arranged and opened to the public, followed by interactive Q&A between the audience on land and scientists at sea. This 1-hour online broadcast attracted over 200,000 livestream views.
“For most people, the oceans are wonderful and mysterious. But they remain mostly unknown for oceanographers like us. Surprises and findings can happen during each expedition. Advances in technology that made the deep sea broadcasts possible are changing human’s relationship with the oceans,” said Prof. Huaiyang Zhou during the broadcast. “I believe we will see more advances and changes like this, and I also hope that more people can join our oceanographic community.”
