This report preliminarily summarizes the known fossil localities of the Rat Buri Limestone found in the past four paleontological reconnaissances in Thailand held since 1962. In the attached maps the Upper Carboniferous (?) and Permian fossil localities already described or listed in the references published prior to 1962 are also plotted, and the Permian fusulinacean fossils known in these localities are listed in the Table. So far has been known, the Upper Carboniferous (?) -Permian “Rat Buri Limestone” contains not only calcareous sediments but also non-calcareous sediments. In some places it consists exclusively of clastic sediments. Therefore, BORAX and STEWART (1966) suggested that the name of “Rat Buri Limestone”, together with the Kanchanaburi Series, are not adequate for the standard stratigraphic units in Thailand, and should be abandoned. However, since the name of “Rat Buri” has been familiar not only to the Thai geologists but also to foreign workers, the Rat Buri Limestone is retained in this report for the calcareous facies of the Upper Carboniferous (?) to Permian rocks, and the Sara Buri System is tentatively proposed for the time-rock unit covering the Upper Carboniferous (?) to Permian of Thailand.
With rapid accumulation of accurate and detailed dating data for the Neogene rocks, the late Cenozoic time scale has become more reliable in recent years. This paper reviews the time scale with special references to stratigraphic positions of the Aquitanian, the Pontian and the Calabrian-Villafrancian. The Neogene correlation between North America and Europe are also summarized together with the “absolute” chronology.