China’s comprehensive technology system to explore the mysterious deep sea has taken initial shape, after the country’s three marine geological survey vessels completed their first expeditions in the recent two years, said an official with the China Geological Survey (CGS), an institute under the Ministry of Natural Resources on March 6.

Chinese research ship Haiyang Dizhi 9 left a port in Qingdao, eastern China's Shandong province, on Feb. 25, 2019, for a voyage to East China Sea, South China Sea and the western Pacific Ocean. (Photo by Zhang Jingang and Zhang Shusheng from People’s Daily Online)

China's marine geological survey vessel Haiyang Dizhi-10, or Ocean Geology No 10, returned to Guangzhou on Feb. 26 after Chinese and Pakistani scientists completed a joint expedition in the Indian Ocean.

During its first ocean expedition, the vessel voyaged for 91 days for a distance of 26,100 kilometers. Independently designed and built by China, the multifunctional ship is able to garner information about marine geology, geophysics, and hydrological environment.

The ship is seaworthy in all kinds of waters. It is China’s first vessel having a small tonnage but able to drill at great depths.

In Dec. 2018, Chinese research ship Haiyang Dizhi 9, the only Chinese ship able to carry out seismic, geological and geophysical study simultaneously, finished its maiden expedition.

In August of the same year, Haiyang Dizhi 8, which is towed by 6 cables, set sail to the northern waters of the South China Sea for its first marine resources survey. It is China’s first ship for geophysical exploration that can provide high-resolution three-dimensional images.

The three ships, which were all designed and built by China, are younger and have multiple functions compared with other CGS vessels, said the official, adding that they’ve optimized the function complementarity of the research ships and fixed-wing aircraft in marine exploration.

China has achieved continuous breakthroughs in marine research vessel construction as the country becomes stronger.

Back to the mid-1950s, the country transformed fishing boats, tugboats into marine research vessels. In the 1960s, it became one of the world’s first countries to design and build such vessels exclusively for marine research.

In the 1970s and early 1980s, China started to design and massively build such vessels by itself. In the 21th century, the country brought the construction to a fastigium by building ships like the Haiyang-6 scientific research vessel, research vessel Kexue, or "Science", and research vessel Zhang Qian.

The maiden expeditions of the Haiyang Dizhi-10, -9 and -8 research vessels marked a step forward of the country’s equipment and technology, and also sent China to the first echelon of the world in terms of research capabilities in marine geology, geophysics, and drilling.