Developments in geology, historical geology, sedimentology, and paleontology in Japan after the Second World War, from 1945 to 1965 are described. The Geological Society of Japan was reconstructed soon after the war and established the foundations for geological studies. The Tokyo Geographical Society compiled documents on geological research in East Asia before and during the war. The Coal Exploration Advisory Committee (CEAC) and the Petroleum Exploration Advancement Committee (PEAC) made progress on research related to oil and coal. New geological maps were compiled; the nomenclature of strata was formulated; and, regional geologies were summarized. Studies of Precambrian and Paleozoic strata continued to advance, while investigations on the geology of the Mesozoic challenged to establish theories posited before the war. Areas of studies such as “Green tuff,” radiocarbon measurement, tephrochronology, and neotectonics in the Cenozoic strata were opened up. Around 1950, sedimentological themes emerged; the Sedimentology Institute was founded at the University of Tokyo in 1951; and a sedimentology research group was formed in 1957. Research, for example, on recent sediments in Tokyo Bay were started. Soon after the war, the Palaeontological Society of Japan collated data on type species and their descriptions collected since 1868 for the development of palaeontological studies in Japan. Studies on Desmostylus, Naumann elephant, and Metasequoia fossils were launched. Micropaleontology including foraminifera studies made remarkable contributions.
