Abstract: Launched in 1981,the journal "Marine Geology and Quaternary Geology" published thirty volumes, and like tree rings the thirty volumes have recorded the development of marine geology over the 30 years of China's reform and opening-up. Today the Chinese marine science community is on the march to the deep open ocean, getting active on the ocean science frontiers. As shown by recent discoveries, the deep sea floor provides a passageway between the surface and interior parts of the Earth system, and its understanding has become a bottleneck in the Earth system studies. On the other hand, the marine science is now at the transition from "expedition" to "observation", and the sea-floor observatories are building up the third platform for the Earth system observation. Looking forward to the 30 years ahead, the "Marine Geology and Quaternary Geology" will mirror the progress of marine geology in China, keeping track of its growth in the international scientific arena.