摘要

International Ocean Discovery Program (IODP 2013-2023) and its predecessors is the largest and longest international cooperation research program in earth science. It requires a strong financial support from government. Therefore, a study to compare research achievements among main IODP members was carried out. All peer-reviewed publications related with IODP can be acquired through database built by American geosciences institute. Comparisons of research directions and focus among the United States, Japan, Germany and P. R. China were studied using term frequency-inverse document frequency matrix, co-word, co-citation cluster and overlay analysis methods. Publication numbers, collaboration network, annual variation and expedition achievements among IODP main members were analyzed at the meantime. Research output differences in ocean science among IODP main members were also covered and compared with IODP outputs.US has emerged as absolutely the leader of IODP. Japan, Germany, UK and France are close followers, and these countries also have their own research topics. P. R. China ranks six with publication number and ranks ten with first authors and corresponding authors. There is a large gap between P. R. China and other countries such as US and Japan, which lies in expedition chief scientists' percentage, basic researches and activeness in research focus. Besides, researches output performance of P. R. China in ocean science is better it ranks 2 in ocean science publications. What is more, Japan has a trend to catch US, however, P. R. China doesn't have any sign of increasing. Sustained fiscal effort is still necessary for P. R. China.