China's scientific research ship Tansuo-1 returned to a port in Sanya city, South China's Hainan province, on Dec 5, after completing its deep-ocean expedition to the Mariana Trench.

Aboard the research vessel was China's self-developed deep-sea manned submersible Fendouzhe (Striver), which successfully conducted 23 dives, with six exceeding a depth of 10,000 meters during the 53-day voyage that started on Oct 14.

It also completed the scientific expedition in the Challenger Deep of the Mariana Trench, the deepest known point in Earth's oceans.

Scientific researchers collected several large organisms, in-situ micro-organisms, sediments and rock samples, accumulating valuable data for use in genetic research on the area and understanding its geological structure, according to the Institute of Deep-sea Science and Engineering under the Chinese Academy of Sciences.

Seventeen scientific and technical personnel from seven institutions across the country, including five female scientists, dove for the first time with Fendouzhe, with eight of them going as deep as 10,000 meters for the first time.

So far, the manned submersible has completed 21 dives with a depth of 10,000 meters, carrying 27 scientists in China to the deepest parts of oceans.

During the voyage, Chinese research teams participating in the expedition jointly initiated the Mariana Consensus. It calls for the establishment of a standardized system for deep-sea expeditions to realize the long-term preservation and sharing of deep-sea scientific samples and data.

The team also launched the Mariana Trench Environment and Ecology Research Project (MEER) during the expedition. The project aims to invite more researchers from home and abroad to join in the MEER, so as to tackle major scientific issues together, such as the origins of life and environmental adaptation, biodiversity and climate change, among others.