Collection sediment from Mariana Trench with a novel pressure-retaining sampler

Sediments in the hadal trenches have been proved to contain a large number of specific microorganisms. In this study, we developed a pressure-retaining sampler for the hadal trenches. A novel piston sampling mechanism was designed, the weight of which is light enough to be mounted on a lander for field tests. Furthermore, laboratory tests validated its high-pressure resistance and pressure-retaining performance. We tested the penetration force and the sampling performance in different clays. Moreover, a pressure compensator was designed based on the actual gas state under high pressure. Finally, a prototype of the sampler was built and field tested in the Mariana Trench. The results indicated that the sampler has an excellent pressure-retaining capacity and can collect sediment samples at the deepest point of the in the world's ocean.